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Journal of Food Biochemistry

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ISSN (Print) 0145-8884 - ISSN (Online) 1745-4514
Published by John Wiley and Sons

[1587 journals]

Phenolic Composition and Bioactive Properties of Cell Wall Preparations and Whole Grains of Selected Cereals and Legumes
- Authors: Sule O. Salawu; Megan J. Bester, Kwaku G. Duodu
  Pages: n/a - n/a
  Abstract: Phenolic compounds are associated with cell walls in cereals and legumes. Phenolic composition and bioactive properties of cell walls and whole grain of sorghum, teff and cowpea were determined. Whole grain extracts had higher total phenolic content (630–2,782 mg CE/g) and total flavonoid content (0.033–0.17 mg CE/g) than cell wall extracts (261–1,005 and 0.011–0.047 mg CE/g, respectively). Similar trends were observed for 2,2'‐azinobis (3‐ethyl‐benzothiazoline‐6 sulfonic acid) radical scavenging (whole grain: 30–87; cell wall: 22 μM TE/g), oxygen radical absorbance capacity (whole grain: 47–964; cell wall: 40–183 μM TE/g) and ferric reducing power (whole grain: 85–279; cell wall: 41–95 mg vitamin C equivalent/g). Whole grains contained both phenolic acids and flavonoids. Ferulic acid was a major component of cell walls. Whole grain and cell wall extracts inhibited low‐density lipoprotein oxidation and protected against oxidative DNA damage. Cereal and legume cell walls may be considered important potential contributors to human health because of their phenolic composition. Practical Applications Phenolic compounds in cereals and legumes are important components of dietary fiber in which they occur mainly in association with cell wall components. There is increasing research focus on phenolic compounds due to their bioactive properties and potential health benefits. Investigation of the cell wall‐bound phenolic compounds is necessary to establish their potential contribution to human health. In this study, the phenolic composition and antioxidant activities of extracts from cell wall preparations and whole grain of selected cereals and legumes of importance in Africa, as well as their protective effect on oxidized DNA damage and copper catalyzed low‐density lipoprotein oxidation, were determined. This research provides insight into the potential health benefits offered by the grains studied, such as prevention of chronic diseases of lifestyle and the importance of the bioactive phenolic constituents of cell walls in this regard.
  PubDate: 2013-04-25T03:42:52.769143-05:
  DOI: 10.1111/jfbc.12026
Angiotensin I–Converting Enzyme Inhibitory Peptides from Snakehead Fish Sarcoplasmic Protein Hydrolysate
- Authors: Masomeh Ghassem; Abdul Salam Babji, Mamot Said, Fatemeh Mahmoodani, Keizo Arihara
  Pages: n/a - n/a
  Abstract: In this study, the angiotensin I‐converting enzyme (ACE) inhibitory peptides were isolated from snakehead fish sarcoplasmic protein hydrolysates. Enzymatic hydrolysis of sarcoplasmic protein was performed using various commercial enzymes. The alcalase hydrolysate with the highest ACE inhibition activity was purified with gel chromatography and reversed phased high‐performance liquid chromatography. The purified fractions were then subjected to electrospray ionization quadrupole‐micro‐time‐of‐flight mass spectrometry for amino acid characterization. Two novel ACE inhibitory peptides LYPPP and YSMYPP with IC50 values of 1.3 and 2.8 μM were identified, respectively. The pattern of ACE inhibition, resistance to hydrolysis by gastrointestinal proteases and cytotoxic potencies of isolated peptides were described. The results showed no cytotoxicity of peptides on human embryonic fibroblast cell line (MRC‐5) and human hepatocarcinoma cell line (HepG2). Practical Applications Freshwater fish muscle proteins and their hydrolysates offer huge potential as novel sources of natural bioactive peptides with angiotensin I‐converting enzyme (ACE) inhibitory activity. The present study revealed the identification of two strong ACE inhibitory peptides obtained from alcalase hydrolysis of snakehead fish sarcoplasmic protein. However, further studies are required to determine the in vivo antihypertensive activity of the purified potent ACE inhibitory peptides.
  PubDate: 2013-04-17T03:27:33.152833-05:
  DOI: 10.1111/jfbc.12031
Phenolic Composition and Antioxidant Properties of Anzer Bee Pollen
- Authors: Esra Ulusoy; Sevgi Kolayli
  Pages: n/a - n/a
  Abstract: Seventeen phenolic compounds related to the botanical origins of 13 Anzer pollens from Turkey have been analyzed by RP‐HPLC. LOD values of standards were found to be between 0.0192 and 0.1313 mg/L with good linearity (r > 0.9977). The mean content of identified total phenolics ranges from 0.5 mg/100 g pollen to 2.6 mg/100 g pollen. While a common profile of phenolic compounds comprising p‐OH benzoic acid, vanillic acid, caffeic acid, syringic acid, p‐coumaric acid, ferulic acid, rutin, trans‐cinnamic acid, and cis,trans‐abscisic acid was detected in all Anzer pollen, catechin was not determined in any of the pollen samples. Furthermore, antioxidant properties of pollens were determined using total phenolic content, FRAP, CUPRAC and DPPH● (2,2‐diphenyl‐1‐picrylhydrazyl) radical‐scavenging activity tests. The antioxidant activities showed a marked correlation with total phenolics. Practical Applications Bee‐collected pollen is one of the richest and the purest natural food supplements packed by honeybees into granules and subsequently harvested from hives by humans. Bee pollen is composed of nutritionally essential substances such as carbohydrates, proteins, amino acids, lipids, vitamins, mineral substances and trace elements. It also contains considerable amounts of polyphenolic substances, mainly flavonoids, which are regarded as potent antioxidants. Flavonoids can be used to evaluate botanical origin and to set up quality standards for the assessment of nutritional and physiological properties of bee pollen. This paper provides an applicable RP‐HPLC method for the determination of 17 phenolic compounds in Anzer pollens and for the investigation of their total phenolic contents and antioxidant capacities.
  PubDate: 2013-04-17T03:27:20.043165-05:
  DOI: 10.1111/jfbc.12027
Antioxidant and Antiproliferative Activities of Extracts of Selected Red and Brown Seaweeds from the Mandapam Coast of Tamil Nadu
- Authors: Kavitha Murugan; Vidhya V. Iyer
  Pages: n/a - n/a
  Abstract: Antioxidant and antiproliferative activities were examined for methanol (M), chloroform (C), ethyl acetate (E) and aqueous (A) extracts of Turbinaria ornata, Kappaphycus alvarezii, Acanthophora spicifera and Gracilaria corticata, using 2, 2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging, beta‐carotene bleaching inhibition, ferrous ion chelation, total reducing activity and resazurin‐based growth inhibition (in A549, HCT‐15, MG‐63 and PC‐3 cell lines) assays. Higher growth inhibition was observed in A549 and MG‐63 cells with higher values of total flavonoid content, DPPH radical scavenging and total reducing activities, and in PC‐3 cells with higher beta‐carotene bleaching inhibition. Positive correlation (P
  PubDate: 2013-04-14T23:04:27.776514-05:
  DOI: 10.1111/jfbc.12029
Antilisterial Effect of Essential Oil and Extracts of Poncirus trifoliate Rafin. Seeds
- Authors: Atiqur Rahman; Sharif M. Al‐Reza, Sun Chul Kang
  Pages: n/a - n/a
  Abstract: The in vitro antilisterial potential of the essential oil and various organic extracts of Poncirus trifoliata Rafin. seed was evaluated. The oil and organic extracts of chloroform, ethyl acetate and methanol revealed a remarkable antilisterial effect against all strains of Listeria monocytogenes ATCC 19111, 19116, 19118, 19166 and 15313. Also, the oil had a strong detrimental effect on the viable count of the tested Listeria spp. Practical Applications Medicinal plants are natural resources, yielding valuable herbal products that are often used in the treatment of various ailments. Poncirus trifoliata Rafin. is a deciduous or semi‐deciduous shrub, native of China and Korea, and is also known as the Korean bitter orange. Traditionally, trifoliata oranges (P. trifoliata) have been widely used in folk medicine as a remedy for gastritis, dysentery, inflammation, digestive ulcers, etc. Our results showed that essential oil and various extracts derived from the seeds of P. trifoliata have potential activity against Listeria spp. Thus, it may conclude that the natural compounds derived from essential oil and extracts might be suitable for use as preservatives to control foodborne pathogens.
  PubDate: 2013-04-09T22:25:26.218573-05:
  DOI: 10.1111/jfbc.12024
Antioxidants in Italian Head Lettuce (Lactuca sativa var. capitata L.) Grown in Organic and Conventional Systems under Greenhouse Conditions
- Authors: Alessandra Durazzo; Elena Azzini, Maria Claudia Lazzé, Anna Raguzzini, Roberto Pizzala, Gianluca Maiani, Lara Palomba, Giuseppe Maiani
  Pages: n/a - n/a
  Abstract: Lettuce belongs to the Asteraceae family and it is native of the Mediterranean region. In our research, the effect of cultivation practices (organic versus conventional) on antioxidants in Italian head lettuce (Lactuca sativa var. capitata L.) grown in greenhouse was investigated. Bioactive molecule levels, antioxidant properties and the cytotoxicity of polyphenolic extracts from the edible part of head lettuce in Caco‐2 cells were determined. FRAP values are 5.33 ± 0.35 and 6.35 ± 0.08 mmol/kg in organic products and 4.83 ± 0.16 and 1.80 ± 0.04 mmol/kg in conventional products. FRAP values differ significantly (P
  PubDate: 2013-04-08T02:39:44.110495-05:
  DOI: 10.1111/jfbc.12025
Phenolic Contents, Antioxidant and Anti‐inflammatory Activities of Asparagus cochinchinensis (Loureiro) Merrill
- Authors: Nadira Binte Samad; Trishna Debnath, Md. Abul Hasnat, Mehnaz Pervin, Da Hye Kim, Jeong Eun Jo, Sa Ra Park, Beong Ou Lim
  Pages: n/a - n/a
  Abstract: Asparagus cochinchinensis (Loureiro) Merrill. (AC) is used as a traditional medicine for treating inflammation and oxidative stress‐related diseases. In this study, aqueous extract of AC tuber was investigated to determine the antioxidant and anti‐inflammatory activities. Free radical‐scavenging activities as well as total phenolics and flavonoid contents of the extracts were measured. As primary screening of anti‐inflammatory activity, cell viability and inhibition of nitric oxide (NO) production were determined using the lipopolysaccharide‐treated RAW 264.7 macrophage cell line. The levels of phenolic and flavonoid compounds from AC were found to be 459 ± 1 μg gallic acid equivalent/g (GAE/g) dry mass and 642 ± 4 μg catechin equivalent/g (CE/g) dry mass, respectively. AC showed 2,2‐diphenyl‐1‐picrylhydrazyl 1,1‐diphenyl‐2‐picrylhydrazyl, nitrite scavenging and hydroxyl radical‐scavenging activity in a dose‐dependent manner. Significant NO production and cell viability were also found in the extracts. Results suggest that AC can be a source of natural antioxidants and anti‐inflammatory substances. Practical Applications Asparagus cochinchinensis has been used in traditional Chinese medicine for over 2,000 years. Dried roots are being used for medicinal purposes. The roots contain asparagine, starch, mucilage and sugars. The dried root is antibacterial, anti‐inflammatory, antiseptic, antipyretic, diuretic, expectorant, stomachic, nervous stimulant and tonic. It is taken internally in the treatment of fever, sore throat, debility, coughs, etc. The plant has a folk history for the treatment of cancer. Modern research has detected antitumor activity. It is now being studied for the treatment of lung cancer. The findings of this study can demonstrate the antioxidant and anti‐inflammatory activities of the aqueous extract from A. cochinchinensis dried roots. The effects would be useful to improve human health.
  PubDate: 2013-04-05T06:49:35.932807-05:
  DOI: 10.1111/jfbc.12028
The Extract of Chlorella vulgaris Protects Transformed Retinal Ganglion Cells from Oxidative Stress‐induced Cells Death
- Authors: Kyung‐A Kim; Kwang Hyun Cha, Soon‐Jung Choi, Cheol‐Ho Pan, Sang Hoon Jung
  Pages: n/a - n/a
  Abstract: This study investigated whether an extract of Chlorella vulgaris (ECV) could ameliorate the negative influence of N‐methyl‐d‐aspartate (NMDA) on the retinas of rats and decrease oxidative stress‐induced cell death in transformed retinal ganglion cells (RGC‐5). The ECV was shown to attenuate the negative effect of l‐buthionine‐(S,R)‐sulfoximine (BSO) and glutamate on RGC‐5 cells. ECV also decreased the expression of apoptotic proteins induced by BSO and glutamate. NMDA affected the thickness of the retinal inner plexiform layer (IPL) and increased the number of TUNEL‐positive RGCs. However, ECV treatment was protective against IPL thinning and reduced the number of TUNEL‐positive cells in the ganglion cell layer. Our results clearly demonstrate the neuroprotective effect of ECV on retinal degeneration both in vitro and in vivo. Practical Applications Chlorella vulgaris is used in alternative medicine and traditional foods because of its high nutritional content and significant amounts of lutein, which may be beneficial in protecting against age‐related eye diseases such as cataract, age‐related macular degeneration (AMD), and glaucoma. However, its protective effect against glaucoma‐related retinal ganglion cell degeneration has not been investigated. This study aimed to examine whether the extract of C. vulgaris (ECV) could be protective against retinal degeneration. Our results indicate that ECV can protect retinal cells from oxidative stress‐induced damage both in vitro and in vivo. These effects may be due to the anti‐apoptotic potencies of compounds contained in C. vulgaris. Thus, C. vulgaris may be a useful supplement to prevent retinal degeneration.
  PubDate: 2013-04-03T03:26:42.766862-05:
  DOI: 10.1111/jfbc.12030
Issue Information
- Pages: i - i
  PubDate: 2013-04-02T02:13:16.843106-05:
  DOI: 10.1111/j.1745-4514.2013.00676.x
Spotlight on PGI Sweet Potato from Europe: Study of Plant Part, Time and Solvent Effects on Antioxidant Activity
- Abstract: Sweet potato (SP) has long been used as food and in traditional medicine. For the first time, total antioxidant activity (TAA), reducing power (RP), ferric‐reducing antioxidant power (FRAP) and 1,1‐diphenyl‐2‐picryl‐hydrazyl (DPPH) antioxidant activities from European sweet potato vines holding a Protected Geographic Indication (PGI) were studied through a factorial design. Plant part was the main influential factor followed by solvent acidification. Principal component analysis revealed total phenolic content, total flavonoid content, FRAP and RP assays more related to sample differences (stems or leaves) and DPPH to extraction conditions, namely solvent acidification. The in vitro antioxidant activities of leaves were 1.25 g AAE/100 g dw for TAA and 50.8 g GAE/100 g dw for RP. DPPH scavenging activity was higher than FRAP (i.e., 58.6 and 29.3 and μM Trolox/g dw, respectively). Stems results were 1.3 to 9.2 times lower than leaves. These outcomes confirmed SP leaves a potential resource of antioxidants in the human diet that may add supplementary value to PGI agriculture products. Practical Application Vines, especially leaves, from PGI sweet potatoes could be advantageously used as a natural source of antioxidants, with potential to be used as a food in the diet. Focus on sweet potato of European origin may contribute to increase interest on its cultivation and consumption. In addition, insights on the potential added value present in Protected Geographic Indication (PGI) agriculture products may enhance protected demonization turnover for producers. Industries that pursuit food with functional applications may consider sweet potato vines in their new product development processes, aiming for health benefits.
DNA Protection, Total Phenolics and Antioxidant Potential of the Mushroom Russula Virescens
- Abstract: Antioxidant properties and total phenolic, flavonoid, ascorbic acid, β‐carotene and lycopene contents of ethanol and water extracts from the edible mushroom Russula virescens (RV) were examined in this study. Various experimental models including 1,1‐diphenyl‐2‐picryl‐hydrazyl (DPPH), 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid)diammonium salt (ABTS), nitrite, hydroxyl and superoxide radical scavenging activity, inhibition of linoleic acid oxidation, DNA protection and catalase activity were used to characterize the antioxidant activity of the extracts. The IC50 values for DPPH and ABTS radical scavenging activities were 0.22 and 0.44 mg/mL, respectively, for water extract and 1.90 and 0.65 mg/mL, respectively, for ethanol extract. The levels of phenolic compounds were 8.74 and 2.21 mg gallic acid/100 g dry mass, and flavonoid compounds were 2.83 and 1.02 mg catechin/100 g dry mass for the water and ethanol extracts, respectively. In addition, high‐performance liquid chromatography (HPLC) analyses of RV extract revealed the presence of different phenolic compounds. R. virescens can therefore be considered to be a potential source of natural antioxidants. Practical Application Mushrooms accumulate a variety of secondary metabolites, including phenolic compounds, polyketides, terpenes and steroids. Also, flavoglaucin, a mushroom phenolic compound, has been found to be an excellent antioxidant and non‐mutagenic synergist. In this study, the antioxidative activities of an edible mushroom were investigated in relationship to their total phenolic and flavonoid contents.
Selection of Phytase Producing Yeast Strains for Improved Mineral Mobilization and Dephytinization of Chickpea Flour
- Abstract: Among 600 yeast isolates screened for phytase production, five (Zygosaccharomyces bisporus NCIM 3265 and 3296, Williopsis saturnus NCIM 3298, Zygosaccharomyces priorionus NCIM 3299 and Schizosaccharomyces octosporus NCIM 3297) were selected as potential phytase producers. Phytase activity was found to be cell wall associated with temperature and pH optima of 50C and 4.0, respectively. Highest phytase production was attained in cane juice medium as compared with other media used. Addition of phytase to chickpea flour significantly enhanced mineral mobilization by approximately 20–28%, 26–37% and 24–42% for Zn2+, Fe2+ and Ca2+, respectively, and decreased phytic acid content by about 75–88%. Practical Applications Chick pea is one of the most popular vegetarian foods in most developing countries. It is a rich source of protein and minerals like Ca2+, Mn2+, Fe2+, Cu2+ and Mg2+; but these metal ions are bound to phytic acid, which acts as an anti‐nutrient. Treatment of chickpea flour with yeast phytase hydrolyzed the phytic acid and released the bound metal ions. The ability of yeast phytase to improve mineral mobilization and dephytinization of chickpea flour suggests its potential application in food processing and feed industry.
Comparative Study on the Total Phenolic Content and Radical Scavenging Activity of Common Edible Vegetable Oils
- Abstract: The study investigates the antioxidant potential of commonly used vegetable oils viz., coconut (CNO), sunflower (SFO), rice bran (RBO), groundnut (GNO), sesame (SESO) and mustard oil (MO), where the oils were extracted with methanol; and these methanolic extracts were used for the antioxidant studies. Fatty acid composition by gas chromatography, physicochemical parameters such as specific gravity, refractive index, acid value, iodine value and peroxide value were also analysed. Total phenolic content (TPC) and antioxidant activities of the oils (DPPH, ABTS, superoxide and nitric oxide radical scavenging assays) were evaluated. Phenolic compounds were identified by high‐pressure liquid chromatography (HPLC). Percentage TPC was highest in groundnut oil with 3.09 mg/100 g oil followed by coconut oil, rice bran oil, mustard oil, sunflower oil and sesame oil with 1.8, 0.89, 0.56, 0.49 and 0.33 mg/100 g oil, respectively. The methanolic extracts of oils showed potential antioxidant activity in terms of super oxide and nitric oxide radical scavenging activity. Practical Applications The present study indicated that vegetable oils can contribute to the dietary intake of antioxidants, depending on the processing condition. This is the first study of its kind to investigate and compare the phenolic content by HPLC and also the radical scavenging activity (DPPH, ABTS, superoxide and nitric oxide) of different oils. It was observed that the unrefined oils posses better antioxidant activity than the refined oils, which imply the importance of optimizing and/or modifying the existing steps in the vegetable oil processing to retain the polyphenolic content in vegetable oil without compromising other physicochemical parameters. The study has brought out the importance of polyphenolic compounds in vegetable oil as radical scavenging agents that could be beneficial in the management of many degenerative diseases. This may provide vegetable oils a new dimension in health management other than its traditional uses.
Different Effect of Methanol Extracts and Bioaccessible Fraction of Smilax China on Triglyceride Accumulation in Adipocytes
- Abstract: Smilax china is known to provide various biological activities due to significant amount of phenolic acids such as resveratrol. The objective of this study was to examine the effect of methanol extract and digesta of S. china on triglyceride accumulation in adipocytes. Digesta of S. china was obtained from in vitro digestion simulating human digestive fluids. 3T3‐L1 cells were used for adipogenesis, and triglyceride content was measured with Oil red O staining. Methanol extracts of leaf, stem and root from S. china were effective on decreasing triglyceride accumulation in adipocytes in a dose‐dependent manner. Resveratrol, a major phenolic compound in S. china also induced significant decrease in triglyceride accumulation. Meanwhile, digesta from S. china increased triglyceride accumulation in all parts of the leaf, stem and root, indicating a different pattern with the results from the methanol extract of S. china. Practical Application This finding entails that components in digesta from Smilax china may act like agonists of PPAR‐γ, a key factor to treat insulin‐resistant type II diabetes. Our findings suggest that biological activity of various plants, including S. china, could be different depending on chemical and physiological approach.
Effects of Dioscorea Polygonoides (Jamaican Bitter Yam) Supplementation in Normocholesterolemic and Genetically Modified Hypercholesterolemic Mice Species
- Abstract: The Jamaican bitter yam (Dioscorea polygonoides) contains various bioactive components that may increase oxidative stress in various tissues at relatively high concentrations. The present study therefore investigated the effects of bitter yam supplementation (5%) on the integrity of the liver and kidneys. Two mice strains (inbred C57BL/6 and transgenic C57BL/6‐Tg(APOA1)1Rub/J) were used in the study. Each strain was divided into two groups. One group was fed a basal diet without supplementation, and the second group was fed a basal diet supplemented with the Jamaican bitter yam. The results revealed that the transgenic mice fed diets with and without bitter yam supplementation experienced significant increases in weight, when compared with inbred mice fed similar diets. Hepatoprotective effects were observed in transgenic mice known to possess high serum high‐density lipoprotein (HDL). Oxidative stress was induced in mice fed diets supplemented with bitter yam at a concentration of 5%. Practical Application The Jamaican bitter yam possesses potent anti‐diabetic and hypocholesterolemic properties due to its high levels of sapogenin. Currently, the tuber is consumed in rural areas mostly during times of drought. No toxicology data, however, exist for consumption of this yam species. This study provides information on the possible toxicity from overconsumption and paves the way for future studies to establish an effective consumption dosage. With its potent cholesterol‐lowering capabilities, the Jamaican bitter yam can be exploited in the nutraceutical industry and for the development of other value‐added products for everyday consumption such as baked goods and granola bars, giving them a hypocholesterolemic twist.
Histamine Production and Bacterial Growth in Mackerel (Pneumatophorus japonicus) During Storage
- Abstract: Bacterial growth and histamine formation in mackerel during storage at 0, 4, 15 and 25C were monitored. Histamine production and bacterial multiplication were accelerated with increase of the storage temperature. The highest histamine level of 2,080 mg/kg was detected after 2 days of storage at 25C. Selective media were used for isolation of histamine‐producing bacteria (HPB) and the histamine production was confirmed by high‐performance liquid chromatography analysis. A total number of 305 strains were isolated from spoiled mackerel and 32 of them were identified as HPB. Most of the HPB were isolated from violet red bile glucose agar. Morganella morganii, Citrobacter braakii, Hafnia alvei and Raoultella planticola were confirmed as high histamine‐producing strains, whereas other microorganisms were found to possess weak histamine‐producing ability. Practical Applications In order to effectively inhibit the activity of HPB, it is necessary to have a good understanding of bacterial species contributing to histamine production in mackerel during storage. Therefore, we studied the variation of histamine content and the growth of bacteria related to histamine production in mackerel during storage. Results of this study could be useful to assure the safety of mackerel products by controlling histamine content.
Effect of Heat Treatment and Lyophilization on the Physicochemical Properties of Water‐Soluble Proteins from Silver Carp (Hypophthalmichthys molitrix)
- Abstract: The effect of heat treatment at different temperatures ranging from 30 to 80C on the physicochemical properties of water‐soluble proteins from silver carp (Hypophthalmichthys molitrix) was investigated. Silver carp water‐soluble proteins would suffer huge denaturation and aggregation from 40 to 55C. Both solubility and total sulfhydryl groups remained constant below 40C and sharply decreased from 50 to 55C. Surface hydrophobicity started to increase at 40C and reached maximum at 70C. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis of heated water‐soluble proteins showed that the molecular weights of the main proteins ranged from 30 to 97 kDa. Most of silver carp water‐soluble proteins precipitated at 55C. Lyophilization could increase surface hydrophobicity of water‐soluble proteins, but decrease its solubility and sulfhydryl groups. Practical Applications The results indicate that the physiochemical properties of silver carp water‐soluble proteins were greatly affected by processing and it would be a beneficial ingredient for functional food and pharmaceuticals at proper food processing conditions.
Characterization of Carbohydrates and Their Metabolizing Enzymes Related to the Eating Quality of Postharvest Fresh Waxy Corn
- Abstract: Carbohydrates and their metabolizing enzymes related to sweetness and glutinosity were measured in the fresh waxy corn of “Zhongnuo 1” and “Jingkenuo 2000” cultivars during storage for 4 days at 20C. The contents of sugars decreased to a lesser degree in “Jingkenuo 2000” compared to those of “Zhongnuo 1,” and both cultivars exhibited similar trends in starch content. The amylopectin and total starch contents both increased significantly and then gradually decreased, whereas the amylose content significantly increased. Furthermore, the activities of both uridine diphosphate glucose pyrophosphorylase (UGPase) and starch debranched enzyme exhibited a similar pattern with a single peak curve. The activities of adenosine diphosphate glucose pyrophosphorylase (AGPase) and soluble starch synthase decreased, whereas the activity of granule‐bound starch synthase (GBSS) increased significantly. The activity of the starch‐branching enzyme was mostly constant. Correlation analysis between carbohydrates and metabolizing enzymes indicates that UGPase, AGPase and GBSS may be important enzymes. Practical Applications Fresh waxy corn is widely eaten because of its sweetness and glutinosity, which are the eternal behaviors of related carbohydrate character. Contrary to other fruits and vegetables with high soluble sugar and water content, fresh waxy corn shows high starch content and low water content. Thus, the physiological basis for changes in eating quality may differ between fresh waxy corn and other fruits and vegetables. That means the postharvest changes in carbohydrates of common fruits and vegetables are not applicable to instruct the storage and retail of fresh waxy corn. In this study, we report the changes of related carbohydrates and associated enzyme activities and the correlations between them. The research realizes the reason for eating quality changing and controlling factors. These results can promote the quality of fresh waxy corn in the processing, storage and retail.
Enzymatic Hydrolysis Mixture of Donkey Serum Albumin to Inhibit Tumor Cell Proliferation
- Abstract: In this study, the potential use of donkey serum albumin (DkSA) hydrolysates prepared by tryptic hydrolysis as cancer inhibitor was investigated. DkSA was isolated and purified from donkey plasma by anion‐exchange chromatography on Source 15Q. The DkSA hydrolyzed by trypsin was ultrafiltrated using ultrafiltration membrane with a molecular weight cut‐off of 1 kDa to obtain peptides mixture (HPM). The HPM showed inhibitory effect on the proliferation of different cancer cells, including human leukemia HL‐60 cells, liver hepatoma HepG2 cells and breast cancer MDA‐MB‐231 cells under different concentrations. One of the most effective inhibitions was observed toward leukemia HL‐60 cells with a 50% inhibitory concentration (IC50) of 0.073 mg/mL. Further experiments confirmed that the HPM induced leukemia cell apoptosis, which was observed by transmission electron microscope. However, the HPM had no significant effect on cell cycle distribution. This study suggests that the peptides derived from DkSA could inhibit tumor cell proliferation. Practical Applications Enzymatic degradation products of proteins have multiple functions and the hydrolysates have been applied to produce a variety of functional foods, especially in the application of plant protein hydrolysates. Recently, the application of animal protein hydrolysates is gradually developed, in particular, to be used to inhibit cancer cell proliferation. This study revealed for the first time that hydrolysates of donkey serum albumin by trypsin had a relatively high inhibiting capability in tumor cell proliferation. It was much more effective in inhibiting leukemia cells than inhibiting liver cancer cells and breast cancer cells. The effect suggested that the peptides derived from donkey serum albumin could be functional food for anticancer in the future.
Phytochemical Constituents and Antioxidant Activities of Some Indian Jujube (Ziziphus mauritiana Lamk.) Cultivars
- Abstract: Twenty‐eight varieties of Indian jujube were estimated for various health‐promoting compounds such as ascorbic acid, total flavonoids, flavanol, O‐dihydric phenol and total phenolics. The antioxidant capacity was also measured by cupric reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP) and 1,1 diphenyl‐2‐picryl hydrazyl (DPPH) assays. The ascorbic acid content varied from 47.81 to 160.12 mg/100 g, total phenolics from 48.69 to 196.34 mg/100 g, total flavonoids from 60.32 to 173.11 mg/100 g, flavanol from 25.21 to 70.59 mg/100 g and O‐dihydric phenol from 5.03 to 19.26 mg/100 g fresh weight. The average antioxidant activities were 1.6–6.33 and 1.22–5.49 μM TE/g as determined by the CUPRAC and FRAP assays, respectively. Likewise, according to the results obtained, cv. ZG‐3 was found to exhibit the strongest DPPH free radical scavenging activity followed by Katha Phal and Thar Sevika. The study also revealed a considerable amount of variation among the genotypes tested in relation to their phenolic content and antioxidant activity. Practical Applications Numerous studies have shown that fruits are a rich source of diverse nutrients and non‐nutrient molecules, many of which display antioxidant properties. Indian jujube or ber is an important fruit crop of the hot arid regions in India as it forms an integral part of the life of the locals as a source of nutrition and other purposes. It is therefore important to assess different Indian jujube varieties for the content of various antioxidants in order to better identify their overall nutritional value and to encourage its increased consumption by the general public.
Enhancing Gallic Acid Content in Green Tea Extract by Using Novel Cell‐Associated Tannase of Bacillus massiliensis
- Abstract: Gallic acid content in green tea extract was enhanced by using a novel cell‐associated tannase of Bacillus massiliensis. Biomass that contains tannase was used for this study. The activity of the cell‐associated tannase was stable during 1 week of storage in the refrigerator. Response surface methodology was applied based on central composite design to determine the effects of three independent variables (pH, temperature and incubation time) and their mutual interactions. A total of 16 experiments were conducted; and a statistical model was developed, which predicted 475.74 mg/L gallic acid production at pH 6.2, 36C and incubation period of 16.71 h. The subsequent verification experiments confirmed the validity of the model. Under optimal conditions, 84.7% of the total hydrolyzable tannins were converted to gallic acid and glucose. This naturally immobilized tannase was stable enough to be used for up to 12 runs. Practical Applications The current study shows that naturally immobilized tannase of Bacillus massiliensis can be used instead of artificially immobilized tannase. Such naturally immobilized tannase has many advantages as it avoids expensive and laborious isolation, purification and immobilization. Ease of separation of cell‐associated enzyme from the reaction mixture and absence of any detectable extracellular tannase activity after enzymatic treatment are some of the encouraging facts. Stability during storage up to 7 days, 85% tannic acid hydrolyzing efficiency, activity at pH 3.5–8.0 and operational stability for 12 runs are some of the interesting features of this naturally immobilized enzyme. However, its application for tea treatment will be limited until Bacillus massiliensis gets “Generally Recognized As Safe” status. It can be employed, however, for production of gallic acid from agro residues and production of propyl gallate.
Light Wavelengths Regulate Growth and Active Components of Cordyceps militaris Fruit Bodies
- Abstract: Cordyceps militaris is widely cultivated for functional food in China and Southeast Asia. Daylight was commonly used for development of C. militaris fruit bodies. In this study, effects of light wavelengths (pink light = 1/3,450–460 nm + 2/3,620–630 nm; red light = 620–630 nm; blue light = 450–460 nm) on fruit body's production and contents of bioactive components were investigated. The results are: pink light increased dried matter contents and bioefficiency of fruit bodies to the highest (40.06/6.77%) compared with blue light (24.44/4.86%), daylight (22.69/4.55%) and red light (22.06/4.17%), respectively. Pink light significantly enhanced accumulation of carotenoids. Red light obtained the highest contents of adenosine. Pink light is the most optimal for cordycepin accumulation. In order to get the highest production of adenosine, cordycepin, carotenoids and fruit body at the same time, pink light rather than only traditional daylight should be used in the fruit body development, or light wavelengths were regulated according to target compounds of the fruit bodies. Practical Applications This study indicated that different light wavelengths have significant influences on fruit body development and accumulation of the main active compounds as cordycepin, adenosine and carotenoids. Pink light (1/3,450–460 nm + 2/3,620–630 nm) was optimal for production of adenosine, cordycepin and carotenoids. While the traditionally used daylight proved not suitable for cultivation of Cordyceps militaris. These results provided technological basis for cultivation of C. militaris and a insight to light reaction study on light wavelengths regulating accumulation of secondary metabolites.
Differences between Myrtle Fruit Parts (Myrtus communis var. italica) in Phenolics and Antioxidant Contents
- Abstract: The present work aimed to study the phenolics and antioxidant activity of the methanol extracts of Myrtus communis var. italica whole fruit, seed and pericarp. The total phenol contents varied between different fruit parts; seed extract had higher total phenol content (23.87 mg GAE/g DW) than whole fruit (13.73 mg GAE/g DW) and pericarp (2.76 mg GAE/g DW) extracts. Significant differences were also found in total tannin contents among different myrtle parts, representing 18.01 mg GAE/g DW in seed, 9.11 mg GAE/g DW in whole fruit and 0.79 mg GAE/g DW in pericarp. Concerning total flavonoid contents, the highest values were observed in pericarp (1.33 mg GAE/g DW) and whole fruit (1.21 mg CE/g DW) extracts. The condensed tannin content was relatively low in all samples tested, the highest value being found in whole fruit extract (0.96 mg CE/g DW). The high‐performance liquid chromatography analysis indicated that the main phenolic class was hydrolysable tannins (gallotannins) in seed (80.20%, 8.99 mg/g MS) while the pericarp was characterized by a predominance of anthocyanins (75.40%, 3.74 mg/g DW). The whole fruit contained both hydrolysable tannins 40 (10.31%, 0.69 mg/g DW) originated from seed and anthocyanins (69.36%, 4.64 mg/g DW) originated from pericarp. Antioxidant activities of the methanolic extract from different fruit parts were evaluated by using 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging, β‐carotene‐linoleic acid bleaching and reducing power assays. In all tests, the seed was the part with highest antioxidant potential. Practical Applications Nowadays, the interest in naturally occurring antioxidants has considerably increased for use in food, cosmetic and pharmaceutical products to replace synthetic antioxidants, which are being restricted because of their carcinogenicity. In this study, total phenolic contents and antioxidant properties of myrtle fruit parts (Myrtus communis var. italica) were researched.
Standardized Ethanol Extract of Curcuma longa L. Fermented by Aspergillus oryzae Promotes Lipolysis via Activation of cAMP‐Dependent PKA in 3T3‐L1 Adipocytes
- Abstract: We investigated the effect of standardized ethanol extract from Curcuma longa L. fermented by Aspergillus oryzae (FTE) on lipid accumulation and lipolysis using 3T3‐L1 adipocytes. Treatment with FTE at 100 μg/mL significantly reduced lipid accumulation by 43% as quantified by Oil Red O dye and microscopic observation. Intracellular triglyceride content was also lowered by 60%. To determine the effects of FTE on lipolysis, levels of glycerol release and mRNA expression of lipases were measured. Incubation of 3T3‐L1 adipocytes with 60 and 100 μg/mL FTE dramatically elevated levels of free glycerol released into the medium by 58 and 77%, respectively. Likewise, treatment of mature adipocytes with FTE significantly increased cAMP level by reduction of phosphodiestersae‐3B. Subsequently, FTE clearly increased hormone‐sensitive lipase (HSL) and adipose triglyceride lipase (ATGL) mRNA levels and decreased perilipin mRNA level via cAMP‐dependent protein kinase A (PKA), resulting in lipolysis. Practical Applications Turmeric (the common name for Curcuma longa L.) is an Indian spice derived from rhizomes of the plant Curcuma longa, a perennial member of the Zingiberaceae family cultivated in India and other parts of Southeast Asia. Turmeric has traditionally been used for the treatment of inflammation, menstrual disorders, dyspepsia, vomiting and cancer. In this study, FTE suppressed 3T3‐L1 preadipocyte differentiation and promoted lipolysis via upregulation of mRNA levels of HSL and ATGL by PKA phosphorylation. Our results suggested that FTE could be a candidate for antiobesity treatment through reduction of lipid accumulation and stimulation of lipolysis.
Growth Medium Optimization for Biomass Production of a Probiotic Bacterium, Lactobacillus rhamnosus ATCC 7469
- Abstract: This study was undertaken to determine the glucose, yeast extract, tryptone and Tween 80 concentrations in a cultivation medium for optimal biomass production of a probiotic bacterium, Lactobacillus rhamnosus ATCC 7469. Using response surface methodology, a central composite rotatable design was applied to allocate treatment combinations. A polynomial regression model containing linear, quadratic, cubic and quartic terms was used for analysis of the experimental data. Effects involving all four factors evaluated were found to be significant and the strongest effect was given by tryptone concentration. Estimated optimum conditions of the factors for the growth of L. rhamnosus were as follows: glucose = 4.4% (w/v), yeast extract = 6.0% (w/v), tryptone = 6.0% (w/v) and Tween 80 = 1.1 mL/L. The optimum‐point medium gave higher counts of viable cells, specific growth rate and biomass productivity than de Man, Rogosa and Sharpe and the center‐point media. Practical Applications With increasing demand for food products containing probiotic microorganisms from health‐conscious consumers, there arises a need to establish effective fermentation techniques for probiotic biomass production. Medium formulation, fermentation parameters and fermentor design play important roles to ensure optimal results. This study highlights a statistical approach to optimizing medium formulation for a probiotic lactic acid bacteria strain, which is known for its high nutritional demands. The optimal medium formulation obtained from this study can be used for improving Lactobacillus rhamnosus fermentation as it is capable of producing more viable cells than de Man, Rogosa and Sharpe medium, which is generally recognized and used as a suitable medium for lactic acid bacteria cultivation.
Heat Conditioning of Cucumbers Improves Retention of Sliced Refrigerated Pickle Texture and Appearance
- Abstract: The effects of heat conditioning (HC) pickling cucumbers in 50C water on sliced refrigerated pickle product texture, white appearance, pectic substances and proteins during storage were examined. Conditioning for 45 and 60 min effectively hindered softening and cure appearance development (CAD) during 12 months of storage. Maintenance of firmness and white appearance of sliced pickles was achieved when cucumbers were processed within 1 h after HC and when processing was delayed for 24 and 48 h after HC. Conditioning cucumbers for 60 min prevented changes in the solubility of pectic substances and proteins in the pickled product mesocarp tissue during storage, while major changes occurred in mesocarp of the control treatment. SDS‐PAGE demonstrated the production of low molecular mass proteins in response to HC, and that it enhanced retention of distinct proteins in the refrigerated pickle mesocarp tissue. Retention of pickle product texture and white appearance induced by HC appeared to be associated with stabilization of pectic substances and proteins. Practical Applications HC of cucumbers before processing has potential to substantially enhance retention of texture and white appearance of sliced refrigerated pickles during storage and marketing.
Preparation, Characterization and Antibacterial Activity of 1‐Monoacylglycerol of Adamantane‐1‐Carboxylic Acid
- Abstract: A nontraditional monoacylglycerol, 1‐monoacylglycerol of adamantane‐1‐carboxylic acid (2,3‐dihydroxypropyl adamantane‐1‐carboxylate), has been prepared using the direct addition of adamantane‐1‐carboxylic acid to glycidol. Several reaction conditions were examined in order to improve the reaction yield. Based upon the results of these experiments, the following conditions were recommended: glycidol at 80% molar excess, molar ratio of the adamantane‐1‐carboxylic acid and toluene as a solvent 1:10, chromium (III) acetate hydroxide as a catalyst (0.5% w/w), 96C. Final reaction product with conversion higher than 98% was further analyzed using high‐performance liquid chromatography, gas chromatography‐mass spectrometry, nuclear magnetic resonance analysis and differential scanning calorimetry. The effect exhibited by 2,3‐dihydroxypropyl adamantane‐1‐carboxylate against important species of Gram‐positive and Gram‐negative bacteria was assessed. Results showed that 2,3‐dihydroxypropyl adamantane‐1‐carboxylate at concentrations 1,000–1,500 μg/mL is able to effectively suppress the growth of Gram‐positive bacteria; Gram‐negative species were less sensitive. Practical Applications Monoacylglycerols and their derivatives are widely used emulsifiers in the food and cosmetic industry. Besides emulsifying properties, monoacylglycerols with a broad spectrum of microbicidal activity could have beneficial effect by reducing the undesirable microbial flora and extending the shelf life in food or cosmetic products. The aim of this study is to find a suitable antimicrobial agent that could be used as part of food packaging materials and food foils.
Effects of the Addition of Substrate and Salts in Both the Fructosyltransferase Immobilization and Its Catalytic Properties
- Abstract: The partially purified extracellular fructosyltransferase from Rhodotorula sp. LEB‐V10 immobilized in niobium particles in the presence of 4 and 8% (w/v) of sucrose showed no differences concerning fructooligosaccharide (FOS) synthesis, concluding that the enzymatic active sites are not related to immobilization. When immobilized in the presence of 5 and 10 mM CuSO4, this enzyme presented a slight increase in FOS yield (9–12%). In addition, no FOS molecule was produced when the synthesis was conducted with 10 mM CuSO4. This result might suggest that, besides the strong stabilization, the interaction between salt and enzyme should result in a “safer” conformational structure for the enzymatic active sites. FOS synthesis was also affected by the presence of 10 mM MnCl2 or NaCl, but only in a small scale than with CuSO4. Practical Applications The fructosyltransferase (FTase) from Rhodotorula sp. immobilized in niobium has proven to be a promising biocatalyst for fructooligosaccharide (FOS) production, a prebiotic sugar. Adsorption, a technique for FTase immobilization, presents several advantages, but it can, unfortunately, provide a biocatalyst with lower enzymatic activity depending on how the enzyme is linked to the support particles. Exploring the possibility of increasing FOS production by adding compounds such as sucrose (substrate) or CuSO4 (capable of promoting stability) during the process of adsorption has a great importance because it permits one to evaluate the interactions between enzyme and compound. Furthermore, the addition of salts (also capable of increasing stability) into the reactive medium for FOS production is also important to evaluate in order to understand if stability and higher yields are possible to be achieved together.
Physicochemical Characteristics and Antioxidant Activities of Zizyphus lotus L. Seed Oil
- Abstract: This study was designed to examine both the chemical composition as well as the antioxidant activities of the seed oil extracted from Zizyphus lotus L. The results showed that the neutral lipids were mainly composed of triacylglycerols (92.75% of total lipids). Phosphatidylcholine and digalactosyldiacylglycerol were the main phospholipid and glycolipid subclasses, respectively. Oleic, linoleic and palmitic acids were the major fatty acids in the lipids of Z. lotus seeds. In addition, β‐tocopherol was the predominant tocol at 122.13 mg/100 g seed oil, which was equivalent to 60.41% of the total tocols followed by δ‐tocopherol (13.30%) and δ‐tocotrienol (8.95%). The total phenol and flavonoid contents were 18.45 mg/100 g and 2.31 QE/g oil, respectively, with ferulic acid as the main phenolic acid (1.36 mg/100 g oil). Overall, the strong antioxidant activities suggest that it could be advantageously used as a functional or nutraceutical food in order to prevent or moderate oxidative stress‐related diseases. Practical Applications Zizyphus lotus seed oil is a good source of the unsaturated fatty acids, oleic acid and total tocols, and has the potential to be used as nutrient rich food oil. In addition, it contains a high level of phospholipids with phosphatidylcholine as the major component. Z. lotus seed oil has good natural antioxidant properties. The results suggest that Z. lotus seed oil could be explored as a novel and potential natural antioxidant for use in functional foods and medicine.
Combined Effect of Protease and Phytase on the Solubility of Modified Soy Protein
- Abstract: Soy protein isolate (SPI) was subjected to enzymatic hydrolysis with protease and phytase, and the solubilities of the modified SPIs (MSPIs) were characterized and compared with those of a commercial modified protein (SUPRO 670 IP from the Solae Company, St. Louis, MO). The solubilities of MSPIs showed a typical pH‐dependent curve, shifting upward with an increase of hydrolysis time and enzyme dose. In particular, the solubility at pH 4.5 of the MSPI with degree of hydrolysis of 9.8% increased 9.7‐fold more than SPI. Furthermore, the combined enzymatic treatment (protease and phytase) led to a significantly increased solubility of SPI at pH 4.5, which improved by 11.5‐fold and 1.8‐fold more than SPI and SUPRO 670 IP, respectively. In conclusion, the use of hydrolytic enzymes to synergistically improve solubility in the acidic range of pH may provide a positive impact on the MSPIs as a multifunctional food ingredient. Practical Applications Even though soy protein isolates (SPIs) are used in food industry because of their beneficial health effects as well as specific functional properties, the applications of SPIs to processed foods under acidic conditions are very limited. In this study, SPIs were modified by each or combined enzymatic treatments and their solubilities were compared in a wide range of pH. The solubility of the modified SPI (MSPI) was significantly improved compared with the commercial product. Therefore, the MSPI with enhanced solubility at acidic pH could be used in an extended range of processed foods.
Compound Isolated from the Leaves of Phyllostachys nigra Protects NMDA‐Induced Retinal Degeneration
- Abstract: The luteolin 6‐C‐(6″‐O‐trans‐caffeoylglucoside) (PN6) isolated from Phyllostachys nigra is effective against both the negative influence of N‐methyl‐D‐aspartate (NMDA) to the rat retina and the oxidative stress induced transformed retinal ganglion cells (RGC‐5) death. The PN6 concentration‐dependently inhibited sodium nitroprusside‐induced lipid peroxidation. Treatment of the RGC‐5 with PN6 decreased the apoptotic proteins of poly (adenosine diphosphate‐ribose) polymerase (PARP) and cleaved caspase‐3, and increased the antioxidant proteins of superoxide dismutase (SOD)‐2, catalase and glutathione peroxidase (GPx‐1) expressions by Western blot analysis. The PN6 reduced the thickness of the inner plexiform layer using hematoxylin and eosin staining and decreased the number of terminal deoxynucleotidyl transferase 2′‐deoxyuridine 5′‐triphosphate nick‐end labeling (TUNEL)‐positive cells using TUNEL kit assay. Moreover, PN6 attenuated upregulation of apoptotic proteins (PARP and cleaved caspase‐3) and downregulation of antioxidant proteins (SOD‐2, catalase and GPx‐1) caused by NMDA in the rat retina. Practical Applications The aim of this study was to determine whether the luteolin 6‐C‐(6″‐O‐trans‐caffeoylglucoside) (PN6) previously isolated from Phyllostachys nigra is effective at blunting the negative influence of N‐methyl‐D‐aspartate (NMDA)‐induced excitotoxicity in situ. The treatment of the PN6 was evaluated by lipid peroxidation studies, which showed that PN6 significantly inhibited lipid peroxidation with an half maximal inhibitory concentration (IC50) of 1.05 μM. PN6 decreased the upregulation of poly (adenosine diphosphate‐ribose) polymerase (PARP) and cleaved caspase‐3 and the downregulation of superoxide dismutase (SOD‐2), catalase and glutathione peroxidase (GPx ‐1) in retinal ganglion cells. Intravitreal injection of NMDA to the rat retina reduced the thickness of the inner plexiform layer and increased the number of terminal deoxynucleotidyl transferase 2′‐deoxyuridine 5′‐triphosphate nick‐end labeling‐positive cells, which was partially, but significantly blunted by the presence of PN6. Moreover, PN6 blunted the changes in PARP, cleaved caspase‐3, SOD‐2, catalase and GPx‐1 proteins in the rat retina. Evidence is therefore provided to show that P. nigra can be considered as a candidate neuroprotectant for the treatment of various neurodegenerative diseases.
Simultaneous Determination of Seven Flavonoids in Dan Bamboo Phyllostachys glauca McClure Leaf Extract and in Commercial Products by HPLC‐DAD
- Abstract: Flavonoids are a group of polyphenolic compounds with health‐related properties. The leaves of Phyllostachys glauca McClure are rich in flavonoids and its extracts and extract products are the functional ingredients in several commercial products, such as food additives. A new high‐performance liquid chromatography (HPLC) technique was developed and used to analyze seven flavonoids in commercial extract products and P. glauca McClure leaf extract. The leaf extract was purified using column chromatography with macroporous absorption resin (AB‐8) before analysis. After a 2‐h hydrolysis, the seven flavonoids were simultaneously quantified using HPLC with an ultraviolet photodiode‐array detector at 350 nm. Identification of the seven flavonoids (isoorientin, orientin, vitexin, isovitexin, luteolin‐6‐C‐arabinoside, luteolin and tricin) was confirmed by a liquid chromatography mass spectrometer system. Validation was achieved, proving that this method can be used to determine trace amounts of these seven flavonoids in P. glauca McClure leaf extracts and in commercial extract products. Practical Applications Phyllostachys glauca McClure leaf extract has been used as a food‐based antioxidant and functional food additive. Many commercial products made from P. glauca McClure leaf are sold in the Chinese market. At present, spectrophotometry is the primary method used to determine flavonoid content in bamboo leaf extract and extract products. However, the results of spectrophotometry are easily affected by the other compounds present in a sample, such as anthocyanosides, phenol acids and other phenol compounds. This study provides a novel high‐performance liquid chromatography‐photodiode‐array detector method, which has been developed for simultaneous quantification of seven flavonoids in commercial extract products and P. glauca McClure leaf extract. The hydrolysis sample preparation process and simultaneous determination of seven flavonoids render this method suitable to routine quality assurance analyses for active ingredients commercial extract products and P. glauca McClure leaf extracts. This is of great importance to the pharmaceutical and food additive industry.
Purification and Characterization of a Trypsin‐Like Protease from Flatfish (Paralichthys olivaceus) Intestine
- Abstract: A trypsin‐like protease was purified from the intestine of flatfish (Paralichthys olivaceus) by gel filtration and anion‐exchange chromatography. The molecular weight was estimated to be 29.6 kDa by sodium dodecyl sulfate–polyacrylamide gel electrophoresis. Flatfish protease had maximal activity at 70C and pH 7.5 using N‐α‐benzoyl‐dl‐arginine‐ρ‐nitroanilide as substrate. It was stable to heat treatment up to 50C and to pH ranges between 7.0 and 10.0. It was activated by calcium ion and completely inhibited by mercury ion and known serine‐protease inhibitors, such as phenylmethylsulfonyl fluoride, tosyl lysine chloromethyl ketone and benzamidine.Flatfish trypsin could be an alternative to commercial trypsins in a wide variety of applications in the food, detergent and pharmaceutical industries. In the food industry, trypsin is used to produce protein hydrolysates, extract flavor, tenderize meat and improve oil extractions. It is also used in detergent, bating of leather and in diabetes diagnosis and therapy. Moreover, it can break down tumors and cancer cells in cancer therapy.
Total Phenol Content, Antioxidant Activities and α‐Glucosidase Inhibition of Sesame Cake Extracts
- Abstract: Sesame cake, the byproduct obtained after the removal of oil is presently used as cattle field. Present study evaluates the α‐glucosidase, α‐amylase inhibition and antioxidant properties of black sesame cake extracts. For that purpose, defatted seeds were sequentially extracted with ethyl acetate, methanol, methanol‐water 70:30 (v/v) and water. Among the extracts tested, methanol extract demonstrated better antioxidant activities (2,2‐diphenyl‐1‐picrylhydrazyl, hydroxyl and superoxide radical) and total phenol content. But the total flavonoid content and the total reducing power was high for methanol‐water. Most active methanol extract was further screened for α‐glucosidase and α‐amylase inhibition. The extract showed strong α‐glucosidase inhibitory potential and mild α‐amylase inhibition. The study indicated that the extraction yield and the antioxidant activities were strongly dependent on the solvent, antioxidant assays and extract concentration. These results demonstrated that sesame meal can be exploited as source of protein and bioactive for the development of functional food.Sesame seed is one of the most important oil seed crops in the world. Defatted sesame meal, the byproduct obtained after the removal of oil is mainly used as a cattle feed aside from being a good source of protein and antioxidants. This study conducted using sesame meal extracts has revealed the inhibitory potential of the extracts against two carbohydrate digestive enzymes: α‐glucosidase and α‐amylase. The meal extract showed the presence of phenolics and flavonoids and also showed antioxidant activities. This study thus provides the biochemical rationale for further in vivo studies and utilization of this byproduct for development of functional food for the management of diabetes.
Effects of Previous Gutting on Biochemical Changes and Profile of Long‐Chain Polyunsaturated Fatty Acids in Cold‐Smoked Kutum (Rutilus frisii kutum) Stored at Room Temperature (25 ± 2C)
- Abstract: Previous gutting was applied to fresh kutum (Rutilus frissi kutum) to study the effects of cold smoking on the changes of rancidity and fatty acid (FA) content of the gutted and ungutted smoked kutum stored at room temperature (25 ± 2C) for 60 days. To do so, proximate (protein, ash, moisture and lipid), chemical (peroxide value [PV], thiobarbituric acid‐index [TBA‐i], total volatile basic nitrogen [TVB‐N] and FA profile) and pH analyses were carried out. The ungutting of kutum before smoking resulted in a higher degree of bacterial spoilage and oxidation during storage at room temperature, based on the results obtained from PV, TBA‐i, TVB‐N and FA content analyses. Moreover, pH as a critical factor on food spoilage showed a less decrease in smoked ungutted kutum during the 60‐day storage. It is concluded that the gutting of kutum before cold smoking is recommended as a pretreatment for storage at room temperature.The results of this study can be applied to improve the existing methods of kutum processing. The findings show that the previous gutting has a proper effectiveness on the chemical quality, content of polyunsaturated fatty acids and nutritional value of cold‐smoked kutum. These findings can be used by researchers as well as manufacturers in the economical preparation of cold‐smoked fish products. Based on these results, suitable methods of smoking and preservation techniques can be developed to improve the shelf life of cold‐smoked kutum in Iran.
Goldenberry (Physalis peruviana) Juice Rich in Health‐Beneficial Compounds Suppresses High‐Cholesterol Diet‐Induced Hypercholesterolemia in Rats
- Abstract: Goldenberries (Physalis peruviana) are a promising exotic fruit that could be a subject of many novel foods. No reports are available on the effect of administration of goldenberries on different aspects of blood profile in experimental animals. The objective of this study was to investigate the effect of feeding goldenberry juice on hypercholesterolemia by analyzing the changes in the blood profile of high‐cholesterol diet (HCD)‐fed rats. The chemical composition and antiradical properties of juice were determined. Generally, rats fed with goldenberry juice showed lower levels of total cholesterol, total triacylglycerol and total low‐density lipoprotein cholesterol, as well as higher levels of high‐density lipoprotein cholesterol in comparison with animals fed with HCD and cholesterol‐free diet. Juice administration induced a decrease in the activity of glutamic pyruvic transaminase compared with the positive control group after 2 months of administration. There was a remarkable decrease in total serum protein, albumin and globulin for groups treated with goldenberry juice. Histological examination of the liver and kidney were also conducted. The results demonstrated that consumption of goldenberry juice may provide beneficial effects on reversing HCD‐associated detrimental changes.The administration of goldenberry juice has a profound influence on the metabolism of lipids and positively affects the blood profile of rats fed with a high‐cholesterol diet (HCD). The results suggest that goldenberry juice has significant hypocholesterolemic activities. In addition, goldenberry juice seems to protect the liver in response to oxidative stress (probably via the elevation of antioxidant enzymes levels) as well as alleviate the magnitude of fatty liver development in response to HCD. Therefore, goldenberry juice with high antioxidant potential could be helpful for patients suffering from coronary atherosclerosis.
Antioxidant Activities In Vitro of Ethanol Extract and Fractions from Mushroom, Lenzites Betulina
- Abstract: The antioxidant potential of different fractions of Lenzites betulina was investigated. Fraction 2 showed the highest antioxidant activity in the 2, 2‐diphenyl‐1‐picrylhydrazyl (DPPH) and hydroxyl (OH) radical‐scavenging assays. Three natural p‐terphenyls were identified in this fraction. The structure of a new natural compound was established as 2‐phenyl‐[1H‐2‐benzopyran][4,3‐e][p]benzoquinone in addition to two other compounds, 2,5‐diphenyl‐3,6‐dimethoxy‐p‐benzoquinone and 2‐phenyl‐3‐methoxy‐[1H‐2‐benzopyran][4,3‐e][p]benzoquinone that have been previously reported in L. betulina. The antioxidant activities of these p‐terphenyls were evaluated by DPPH and OH radical‐scavenging assays. 2‐phenyl‐3‐methoxy‐[1H‐2‐benzopyran][4,3‐e][p]benzoquinone was the most active in the OH radical‐scavenging test (IC50 = 37.69 μg/mL) and showed little inhibition in the DPPH assay. The chemical components of L. betulina therefore have some antioxidant capacities, and this species could be used as a potential source of new natural antioxidants.Lenzites betulina has been used as a kind of medicinal fungus in China. In order to find its potential application, the antioxidant potential of L. betulina was investigated. It was found that the total ethanol extracts and the fraction 2 of L. betulina showed strong antioxidative capacity in the 2, 2‐diphenyl‐1‐picrylhydrazyl and hydroxyl (OH) radical‐scavenging assays. The OH radical‐scavenging activity of the fraction 2 (IC50 = 19.42 ± 0.4 μg/mL) was similar to that of ascorbic acid (IC50 = 20.55 ± 0.2 μg/mL). Meanwhile, three natural p‐terphenyl (a new natural compound and two known compounds) were identified in this fraction. Compound 2 showed the most activity in the OH radical‐scavenging test (IC50 = 37.69 μg/mL), so this species could be used as a potential source of new natural antioxidants.
Purification and Partial Characterization of Trypsin from the Viscera of Tropical Sierra (Scomberomorus Sierra) from the Gulf of California
- Abstract: Trypsin from the viscera of sierra (Scomberomorus sierra) was purified by affinity chromatography on Sepharose‐4B coupled to soybean trypsin inhibitor and characterized with respect to its purity, sensitivity to temperature, pH and inhibition. Trypsin was purified from sierra viscera with 11.9‐fold and 29.7% yield. The enzyme had a molecular weight of 25.4 kDa estimated by SDS‐PAGE and two possible trypsin isoforms were observed in activity gels. Trypsin activity was strongly inhibited by soybean trypsin inhibitor and porcine trypsin inhibitor, showing a partial inhibition by a serine protease inhibitor. The optimal activity of the enzyme was observed at pH 9 and 60C with n‐α‐benzoyl‐dl‐arginine‐p‐nitroanilide as a substrate. The enzyme maintained more than 50% of its activity in temperatures up to 50C and within the pH range of 8–10 for a period of up to 2 h.The potential applications of purified trypsin from tropical sierra fish viscera are those that are already in use for trypsin, such as an aid for hydrolysis of food proteins, as an aid in reducing viscosity of stickwater from fish processing plants, and in obtaining bioactive fractions from protein hydrolisates. Specific uses of this particular trypsin from tropical sierra could be those that comply with the optimum conditions at 60C and pH 9–10 or stability described in the results.
ANTIOXIDANT POTENTIAL AND OXIDATIVE DNA DAMAGE PREVENTIVE ACTIVITY OF CHRYSANTHEMUM INDICUM EXTRACTS
- Abstract: ABSTRACTThe objective of this study was to characterize the antioxidant properties of the extracts from Chrysanthemum indicum flower (CIF). The water and ethanol extracts were prepared from CIF and its antioxidant activity was investigated in vitro by different methods including 1,1‐diphenyl‐2‐picrylhydrazyl, 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) diammonium salt, hydroxyl and superoxide radicals and nitrite scavenging, reducing (Fe3+ to Fe2+) power, linoleic acid oxidation inhibition as well as free radical‐induced DNA damage prevention activity. The cytotoxic effect of the ethanol extract was determined on chang normal liver cell. The ethanol‐based extract prevented free radical‐induced DNA damage and did not show any cytotoxicity. The antioxidant activity was highly correlated with the observed phenolic and flavonoid contents. The present study suggests that the extracts of CIF could be considered as a potent source of natural antioxidants.PRACTICAL APPLICATIONSChrysanthemum indicum Linné has been used as a traditional medicine for various immune‐related diseases as well as in mixed spices and alcoholic beverages in Korea, China and Japan. The tea prepared from chrysanthemum flower could prevent sore throat and promote the reduction of fever. Recently, Chrysanthemum indicum flower (CIF) extracts has been reported to have therapeutic potential in a variety of immune‐related cutaneous diseases and lowering blood pressure activity. In this context, we studied antioxidant activities and DNA damage preventive activity of CIF. The results suggest that the extract may have potential as a new source of natural antioxidant.
TYPE 2 DIABETES RELEVANT BIOACTIVE POTENTIAL OF FRESHLY HARVESTED AND LONG‐TERM STORED PEARS USING IN VITRO ASSAY MODELS
- Abstract: ABSTRACTFresh pear consumption could provide health benefits by reducing the risk of chronic diseases such as hyperglycemia linked to type 2 diabetes. This in vitro study investigated the phenolic‐linked antihyperglycemia bioactive factors in aqueous and ethanolic extracts of peel and pulp from eight different freshly harvested and long‐term stored pear varieties. Total soluble phenolics, 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging‐based antioxidant activity and associated in vitro alpha‐glucosidase, alpha‐amylase and angiotensin I‐converting inhibitory activities were analyzed. Peel extracts had higher total soluble phenolic content and related antioxidant capacity than pulp extracts. Comice variety had the highest total phenolic contents with positive correlation to total antioxidant activity. Aqueous pulp extracts had high alpha‐amylase inhibitory activities with no correlation to phenolic content. However, the peel ethanolic extracts had the highest alpha‐glucosidase inhibitory activity with positive correlation to total phenolics. This research provides the biochemical rationale for further clinical studies to include pear as part of healthy diet.PRACTICAL APPLICATIONSUsing in vitro structure‐function relevant bioassays to screen a range of fruits and vegetables helps to develop biochemical rationale to target and strategize the increased use of these fresh fruits and vegetables for better health and wellness. Pears, because of their phenolic bioactives, have potential to be included as a part of a comprehensive diet for managing early stages of hyperglycemia linked to type 2 diabetes. This study provides foundation for screening of pears for improving dietary strategies for managing this chronic disease and can be the biochemical rationale for further clinical studies.
EFFECTS OF FRUIT MATURITY ON OXIDATIVE STABILITY OF LAGENARIA SICERARIA (MOLINA) STANDL. SEED OIL EXTRACTED WITH HEXANE
- Abstract: ABSTRACTThe effects of fruit maturity on oxidative stability of LSO were investigated using an accelerated test at 60C for 6 days. Fatty acid composition, Cox, PV, p‐AV, specific extinction at 232 and 268 nm, and TOTOX were used to assess LSO stability. LSO samples from berry seeds at 50‐DAFS, at CPW and at CPW + S60 were analyzed. LSO at CPW was significantly more stable to oxidation than LSO at 50‐DAFS and CPW + S60. This oil had lower p‐AV than control (peanut oil) and other sources of LSO. PV, specific extinction, TOTOX and Cox of LSO at CPW were also lower than those of 50‐DAFS and CPW + S60, but two times higher than control values. Collectively, these data suggest that LSO cannot be used after 3 days of storage at 60C.PRACTICAL APPLICATIONSThe results obtained showed that the seed oil of oleaginous gourd Lagenaria siceraria (Molina) Standl. was a good source of PUFAs (linoleic acid, an essential fatty acid) for human diet. LSO of CPW could be potentially used for cooking, seasonings and margarine applications because of its high nutritional value and its low linolenic acid content. These seeds could also be used by the food industry for formulating functional foods enriched with PUFAs.
L‐Carnitine Contents in Seafoods Commonly Eaten in Middle Eastern Countries
- Abstract: Beta‐hydroxy‐gamma‐trimethyl amino butyric acid (L‐carnitine) content of raw and cooked seafood was determined using high‐performance liquid chromatography method. Thirty‐one different fish species and nine different crustaceans were used to compare L‐carnitine content of raw and cooked seafood. Significant differences in L‐carnitine content were found in some species, regardless of the raw or cooked seafood (P
ANTIOXIDANT ACTIVITY OF INONOTUS OBLIQUUS GROWN ON GERMINATED BROWN RICE EXTRACTS
- Abstract: ABSTRACTThe aim of this study was to determine the antioxidant activity of different extracts from Inonotus obliquus (IO) grown on germinated brown rice by employing several established methods. The total phenolic and flavonoid contents were performed by Folin–Ciocalteau and aluminum chloride colorimetric assay, respectively. All the extracts showed strong antioxidant activity. However, the ethanol‐based extract showed significantly highest antioxidant activity with the values of the half maximal inhibitory concentration (IC50) for 1,1‐diphenyl‐2‐picryl‐hydrazyl (DPPH), 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) diammonium salt (ABTS), hydroxyl and superoxide radical scavenging activities were 16, 30, 45, and 100 µg/mL, respectively. In addition, the antioxidant activities of IO extracts were highly correlated with the observed total phenolic and flavonoid contents. Our study successfully demonstrates that the extracts from IO could be a potential source of antioxidant as a medicinal and dietary supplement.PRACTICAL APPLICATIONSInonotus obliquus (IO) has been used as a medicine in many Asian countries. IO extracts build up immunity, treat influenza and other viral and bacterial infections, and improves skin elasticity. As a folk remedy, IO was taken in tea or powder form. Japanese scientists reported that topical use of IO helps combat the signs of aging. In Japan, it is used in creams to treat wrinkles. The water extract of IO has antitumor and antimicrobial activities. In addition, hot water extract from IO inhibits the cellular proliferation in cancer cell lines in human stomach. IO is regarded as a “functional food” and believed to promote longevity.
A STUDY ON ANTIOXIDANT CAPACITIES AND FATTY ACID COMPOSITIONS OF TWO DAPHNE SPECIES FROM TURKEY: NEW SOURCES OF ANTIOXIDANTS AND ESSENTIAL FATTY ACIDS
- Abstract: ABSTRACTDaphne (Thymealaceae) species have been widely used in traditional Anatolian medicine. The antioxidant capacity and fatty acid composition of two Daphne taxa (D. oleoides subsp. oleoides and D. serica) were studied. The antioxidant properties of four solvent extracts of Daphne species were assessed using different chemical assays including phosphomolybdate assay, free radical‐scavenging assay, β‐carotene/linoleic acid test system, ferric and cupric reducing power. The total phenolic and flavonoid content of the extracts also were determined. Ethyl acetate, methanol and ethanol extracts obtained from the Daphne species possess strong antioxidant potential. Polyunsaturated fatty acids in the studied oils were the highest level in the fatty acid components. Essential fatty acids accounted for 27.46–45.31% of total fatty acids. These results indicated that the extracts of studied Daphne taxa can be exploited as a source of natural antioxidants and essential fatty acids in pharmacological and food industry.PRACTICAL APPLICATIONSMembers of the genus Daphne have been of great interest owing to their excellent medicinal value. The aim of this study was to discuss antioxidant properties of different solvent extracts and fatty acid composition of two Daphne species. Different chemical assays were performed to antioxidant capacities of the extracts. The results of our in vitro study suggested that the Daphne extracts could be considered as a source of natural antioxidants and essential fatty acids for medicinal and commercial uses.
DETERMINATION OF FLAVOR ESTERS IN ENZYMATICALLY TRANSFORMED COCONUT OIL
- Abstract: ABSTRACTThe lipase‐catalyzed transesterification of coconut oil with fusel oil was investigated in this study. Various aroma‐active octanoic acid esters, such as ethyl‐, butyl‐, propyl‐, isobutyl‐ and (iso)amyl octanoate, were synthesized in addition to other esters. To determine the amount of flavor esters, a simple yet effective sample preparation method through refrigeration was developed to separate valuable fatty acid esters from monoglycerides, diglycerides and triglycerides. With this sample preparation method, gas chromatography coupled with mass spectrometry and flame ionization detector was applied to determine flavor esters in transesterified coconut oil with a total run time of 51 min. The levels of coefficient of variation were within 2% and the recovery rates were in the range of 89.5–100.0%, indicating good accuracy and high precision. The sample preparation and quantification method established appears to be useful for the determination of a wide range of fatty acid esters in oil samples.PRACTICAL APPLICATIONSFatty acid esters, especially short‐chain fatty acid esters, are important flavoring agents applied in the food industry. Using lipase as the biocatalyst to synthesize desirable flavor fatty acid esters from lipids and alcohols is gaining the interest of researchers, since the esters formed by this method are deemed as natural. The reaction equilibrium was achieved at around 20 h. For industrial production of flavor fatty acid esters, it is essential to monitor the amount of these target compounds in the reaction solutions. In this study we developed a simple and effective quantification method to determine the esters in transesterified coconut oil which may also be applicable for the analysis of esters in other oil samples such as lipid‐derived biofuels.
EFFECT OF ACIDIC CONDITION ON PHENOLIC COMPOSITION AND ANTIOXIDANT POTENTIAL OF AQUEOUS EXTRACTS FROM SORGHUM (SORGHUM BICOLOR) BRAN
- Abstract: ABSTRACTThe effect of extraction under acidic condition (pH 2) on phenolic compounds and antioxidant potential of aqueous extracts from condensed tannin sorghum bran was investigated. The protective effect of extracts prepared with water (WE) and acidified water (pH 2) (AWE) against free radical‐induced red blood cell hemolysis and low‐density lipoprotein (LDL) oxidation was determined. The % yield (grams of freeze‐dried aqueous extract/100 g of dry sample weight), total phenolic, flavonoid content and 2,2‐diphenyl‐1‐picrylhydrazyl radical‐scavenging activity were significantly higher in AWE than WE. AWE had 19% higher overall content of identified phenolic acids and flavonoids than WE. AWE showed a significantly higher degree of protection against erythrocyte membrane oxidation than WE. Both extracts showed protective effect against LDL oxidation. However, there were no significant differences in tannin content and oxygen radical absorbance capacity values between the extracts. Extracting sorghum bran under acidic conditions may release bound phenolic compounds thereby improving the health‐promoting benefits of extracts from sorghum bran.PRACTICAL APPLICATIONSThe study shows that aqueous extracts with higher phenolic content, antioxidant activity and potential health benefits can be prepared from condensed tannin bran under acidic condition. Using water as a solvent may be preferred over organic solvents because it is cheaper, environmentally friendly and does not require special handling. The aqueous extracts from sorghum bran may be used exogenously as antioxidant functional food ingredients in the formulation of functional foods with potential health‐promoting properties. This could improve the economic value of sorghum grain.
A PHYSIOLOGICAL INDICATOR TO ESTIMATE ALLICIN CONTENT IN GARLIC DURING STORAGE
- Abstract: ABSTRACTThe aim of the present work was to evaluate the application of a physiological indicator as marker of allicin content during postharvest storage at different temperatures. Sureño INTA garlic cultivar was stored at room temperature (20C ± 3) and cold storage (0C ± 0.5). Samples were taken periodically and allicin, pyruvate content were analyzed and the sprout growth was measured through of the visual index of dormancy (VID). The results showed that regardless of storage temperature, allicin, pyruvate content and VID changed significantly during the period of the assay. For the conditions evaluated, the highest allicin content was observed at 50% and 100% VID. These facts suggest that VID may be a suitable tool to estimate allicin level during storage.PRACTICAL APLICATIONSThis work was addressed to resolve the problem of standardization of garlic subproducts according to their bioactive compounds levels. The information acquired is important for farmers and the food and phytotherapic industry in order to guarantee the adequate supply of garlic subproducts to the consumer. Therefore, we found that it is important to consider a physiological indicator as a tool to estimate the bioactive compound levels during postharvest storage.
ANTIOXIDANT ACTIVITY OF BASIL AND OREGANO EXTRACTS ADDED TO SOYBEAN OIL FOR ACCELERATED STORAGE TEST
- Abstract: ABSTRACTThe objective of this research was to evaluate the antioxidant activity of extract of basil and oregano, and its synergistic effect when added to soybean oil and subjected to accelerated storage test. Extracts of basil, oregano and mixtures of both were applied to soybean oil at a concentration of 2.000 mg/kg, then the extracts were heated in an oven at 60C for a period of 10 days. Samples were taken every 2 days and analyzed for concentrations of peroxides and conjugated dienes. Synthetic antioxidant tert‐butylhydroquinone (TBHQ) at a concentration of 50 mg/kg and soybean oil free antioxidant (control) subject to the same conditions were used as benchmarks. The results showed that the antioxidant effect decreases according to oil heating for all treatments. However, the synthetic antioxidant showed superior protection to the soybean oil during the formation of primary oxidation compounds, followed by the natural extracts, which showed no synergism.PRACTICAL APPLICATIONSThis study can encourage the discovery of new sources of natural antioxidants with significant contribution in the field of health worldwide. It aims at finding effective and less toxic substances to be used in food by evaluating the antioxidant potential of basil and oregano when applied individually or in mixture forms with soybean oil and compared with the synthetic antioxidant TBHQ, currently employed in food industries and target of safety concerns.
BLACK GRAPE JUICE PROTECTS SPLEEN FROM LIPID OXIDATION INDUCED BY GAMMA RADIATION IN RATS
- Abstract: ABSTRACTThis study evaluated the effects of black grape juice (BGJ) against gamma radiation‐induced damage in rats. Rats were exposed (PI) or not (PNI) to radiation and BGJ (2 mL/Kg of body weight) was administrated to irradiated animals (SI) and to nonirradiated animals (SNI). Blood was collected at different time points after irradiation for blood cells counts. The spleen of the animals was removed for weight, lipid peroxidation (LPO) and antioxidant defenses estimation. Blood cell count decreased, whereas LPO and catalase activity increased in spleen along with a decrease in the organ weight after irradiation. Despite the lack of protective effect on hematological parameters and catalase activity, BGJ attenuated LPO induced by gamma radiation. This protective effect seems to be related to the phenolic compounds found in BGJ, such as resveratrol, quercetin and rutin. We demonstrated that BGJ plays a beneficial role in damage caused by gamma radiation by preventing spleen LPO.PRACTICAL APPLICATIONSGrape products, such as black grape juice (BGJ), and their polyphenol compounds have several properties that can be useful in prevention and treatment of many conditions. One of these properties is the antioxidant capacity, which makes of phenolic compounds, such as resveratrol, quercetin and rutin, good exogenous scavengers of free radicals. The present study demonstrates that BGJ exhibits a radiomodifier potential against gamma radiation by exerting antioxidant effects and, hence, it can be used as a valuable agent for managing radiation exposure.
EVALUATION OF ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF TWO ENDEMIC ANTHEMIS SPECIES IN TURKEY
- Abstract: ABSTRACTThe present study was conducted to evaluate the antioxidant and antimicrobial activities of methanol extracts of Anthemis fumariifolia and Anthemis cretica subsp. argaea, which are commonly used in Turkish folk medicine. The total phenolic and total flavonoid contents in the extracts were determined. The antioxidant activities of the extracts were measured employing three methods, namely phosphomolybdenum, 2,2‐diphenyl‐1‐picrylhydrazyl and β‐carotene‐linoleic acid assays. The A. fumariifolia and A. cretica subsp. argaea extracts behaved as strong free radical scavengers with IC50 = 22.65 and 21.43 µg/mL, respectively. In the β‐carotene‐linoleic acid system, A. fumariifolia and A. cretica subsp. argaea extracts exhibited 55.41 and 59.10% inhibition against linoleic acid oxidation, respectively. Antimicrobial activity was assessed by the agar diffusion method against 13 bacteria and two yeasts. Test results showed that the extracts had great potential of antibacterial activity against many bacteria tested. However, they had no inhibitory effect on Candida albicans and Saccharomyces cerevisiae.PRACTICAL APPLICATIONSA. fumariifolia Boiss. and A. cretica L. subsp. argaea (Boiss. & Ball.) Gierson are two species endemic to Turkey. The Anthemis species are known to possess various biological activities and are extensively used as tea in Turkish folk medicine for the treatment of many disorders. The results presented here suggest that the methanol extracts of A. fumariifolia and A. cretica subsp. argaea may possess antioxidant and antimicrobial properties, and can therefore be used as natural agents in the food and pharmaceutical industries.
OPTIMIZATION OF EXTRACTION CONDITIONS FOR ELSHOLTZIA SPLENDENS AND ITS ANTIOXIDANT ACTIVITY
- Abstract: ABSTRACTResponse surface methodology was used to optimize extraction conditions, including ethanol concentration (X1) and extraction time (X2), to obtain the maximal antioxidant activity of Elsholtzia splendens extract. The optimized values of X1 and X2 were found to be 54.61% and 116.8 min, respectively. Experimental results obtained for the optimum extraction conditions agreed favorably with the predicted results, indicating the usefulness of prediction models for antioxidant extractions. This potent antioxidant activity had good correlation with total flavonoid content. The E. splendens extract prepared according to optimal conditions demonstrated a concentration‐dependent α,α‐diphenyl‐β‐picrylhydrazyl (DPPH) scavenging activity and lipid peroxidation inhibitory activity. In conclusion, E. splendens extract prepared by optimal conditions may be useful as a natural functional food ingredient with antioxidant activity.PRACTICAL APPLICATIONSNatural antioxidant compounds have received much attention because of their potential protective effects against free radical damage preventing cardiovascular diseases and tumor formation. Elsholtzia splendens, a subclass of the family Labiatae, is used as an ingredient of traditional medicinal food in eastern Asia. Although many health‐promoting properties of E. splendens were demonstrated by recent studies, in order to develop a functional food derived from new bioactive compounds, such as E. splendens, the extraction steps should be well characterized for the quality of extracts and the efficiency of extraction. In this paper, response surface methodology was used to optimize extraction conditions to obtain the maximal antioxidant activity of E. splendens extract. The optimized E. splendens extract demonstrated a potent radical‐scavenging and lipid peroxidation inhibitory activity. It is expected that the E. splendens extract could be used in a wide range of foods as a potential functional food ingredient.
MODIFICATION OF IgE BINDING TO β‐ AND αS1‐CASEINS BY PROTEOLYTIC ACTIVITY OF LACTOBACILLUS HELVETICUS A75
- Abstract: ABSTRACTProteolytic activity of Lactobacillus helveticus A75 and effects of caseins hydrolysis by this strain on their immuno‐reactivity were studied. Proteases of L. helveticus A75 hydrolyzed both αS1‐ and β‐caseins and were inhibited by serine‐ and metallo‐proteases inhibitors. Polymerase chain reaction amplification revealed the presence of prtH gene, which was 99% identical to prtH gene of L. helveticus CNRZ 32. Effect of proteolysis of αS1‐ and β‐caseins by L. helveticus A75 on their immunoglobulin E (IgE) binding ability was studied by an enzyme‐linked immunosorbent assay with the pool of eight sera from cow milk allergy patients. The IgE binding ability of hydrolyzed proteins was lower than that of intact proteins, which indicates that hydrolysis of αS1‐ and β‐caseins by proteases of L. helveticus A75 decreases their recognition by specific IgE. Half maximal inhibitory concentration values were 2.01 and 2.28 µg/mL for αS1‐ and β‐casein, respectively, and increased until 9.08 and 13.65 µg/mL, respectively, after their hydrolysis by L. helveticus A75.PRACTICAL APPLICATIONSThe obtained results yield new information about proteolytic activity and potential application of lactobacilli isolated from traditional Azerbaijani cheeses. Isolated strain could represent new adjunct cultures for the dairy industry.
TOCOPHEROL CONTENT OF COMMERCIAL FISH SPECIES AS AFFECTED BY MICROWAVE COOKING
- Abstract: ABSTRACTAlpha (α)‐, beta (β)‐, gamma (γ)‐ and delta (δ)‐tocopherol in commonly consumed fish species and also the effects of microwave cooking on tocopherol content of fish were investigated. α‐Tocopherol was found to be the major form of vitamin E in fish muscle. Golband goatfish (47.81 mg/kg), anchovy (40.84 mg/kg), striped sea bream (34.31 mg/kg) and bogue (33.86 mg/kg) had the highest tocopherol content among the samples, whereas the lowest tocopherol levels were observed for silver fish (16.06 mg/kg) and gurnard (18.01 mg/kg). The total tocopherol contents of the cooked fish ranged from 67.78 to 72.875 mg/kg due to the loss of water content in fish muscle. The result of this study showed that fish species had good tocopherol levels for raw and cooked samples. Stability of tocopherol content to microwave cooking in fish muscle was observed.PRACTICAL APPLICATIONSIt is important to achieve a successful determination of the vitamin E constituents that are quantitatively extracted from the food. Although the tocopherol contents of fish vary with different species, α‐tocopherol is the major form of vitamin E in fish muscle. However, various storage temperatures, cooking process and storage time may affect vitamin E levels of fish muscle. Thus, the contents of α‐, β‐, γ‐ and δ‐tocopherol of commercially important fish species were investigated. In addition, the effects of microwave cooking on the tocopherol content of different fish species were investigated. The research findings are important in order to know which fish species has high content of tocopherol and to consider whether cooking process affects tocopherol content in fish.
RELATIONSHIP BETWEEN INDIGENOUS PROCESSING METHODS OF XYLIA XYLOCARPA SEEDS AND THEIR TOTAL FREE PHENOLICS, ANTIOXIDANT ACTIVITY AND HEALTH‐RELEVANT FUNCTIONALITY
- Abstract: ABSTRACTThe methanolic extract of Xylia xylocarpa (Roxb.) Taub. (Mimosaceae) raw seed materials contained total free phenolic content of 14.35 ± 1.66 g catechin equivalent/100 g extract dry matter. Encouraging levels of ferric reducing/antioxidant power (1,096 mmol Fe[II]/mg extract), inhibition of β‐carotene degradation (59.85%) and scavenging activity against 2,2‐diphenyl‐1‐picrylhydrazyl (72.31%) and superoxide (60.31%) radicals were exhibited by the methanolic extract of raw samples. Furthermore, it also recorded 82.23% of α‐amylase and 77.28% of α‐glucosidase enzyme inhibition characteristics under in vitro starch digestion bioassay. Sprouting + oil frying caused a significant increase in the total free phenolic content and also apparent improvement on the antioxidant and free radical‐scavenging activities of X. xylocarpa seeds, while soaking + cooking as well as open‐pan roasting treatments showed diminishing effects.PRACTICAL APPLICATIONSThe consumption of processed legume grains would not only provide the necessary nutrients but also act as potential nutraceuticals and improve the human health. In this connection, in the present study, the antioxidant activity and type II diabetes‐related functionality of methanolic extract of an underutilized food legume Xylia xylocarpa (Roxb.) Taub. were analyzed. A positive correlation between phenolic content and antioxidant activity was established through this investigation. Furthermore, a suitable and minimal processing method has been identified to preserve the health beneficial properties of this wild‐type legume grain. Thus, the suitably processed X. xylocarpa seeds with favorable antioxidant and type II diabetes‐related enzyme inhibition properties could be considered as a potential candidate for the prevention of type II diabetes. The findings of this research work could be more useful in developing/formulating supplementary foods with therapeutic value to alleviate free radical‐mediated chronic diseases, including type II diabetes.
PROOXIDANT AND ANTIOXIDANT ACTIVITIES OF ROSMARINIC ACID
- Abstract: ABSTRACTRosmarinic acid is a fundamental compound of Rosmarinus officinalis. In this work, the intrinsic prooxidant (generation of H2O2 and free radicals by the action of peroxidase) and antioxidant (consumption of H2O2 and free radicals) properties of rosmarinic acid are characterized. In addition, its melanogenic prooxidant activity is characterized as it acts as a substrate of polyphenol oxidase to generate o‐quinones, and its antimelanogenic and, so, antioxidant activity as it carries out the suicide inactivation of polyphenol oxidase. The balance between its pro‐ and antioxidant activities demonstrates that rosmarinic acid can be considered as a net antioxidant.PRACTICAL APPLICATIONSAntioxidants prevent oxidative damage by modulating the oxidative status of cells. The present results indicated that rosmarinic acid is an antioxidant and can act as scavenger of free radicals in biological systems, and could therefore provide health benefits to consumers. Moreover, rosmarinic acid can act as a suicide substrate of polyphenol oxidase and can inhibit the enzymatic browning of vegetables and fruits and melanogenesis in mammals.
ANTIOXIDANT POTENCY, pH AND HEAT STABILITY OF SELECTED PLANT EXTRACTS
- Abstract: ABSTRACTThe potential of methanolic extracts of six green leafy vegetables, viz. Punica granatum, Ipomoea batatas L., Beta vulgaris, Daucus carota, Amaranthus paniculatus and Peucedanum graveolens, as a natural antioxidant was assessed. Two experimental models, namely 1,1‐diphenyl‐2‐picrylhydrazyl radical‐scavenging activity and iron (III) reducing capacity, were used to evaluate the antioxidant activity (AOA) of green leafy vegetables. The stability of extracts to pH (4, 7 and 9) and temperature (100C) was investigated. All the extracts showed varying degrees of antioxidant efficacy in a dose‐dependent manner. P. granatum had high glutathione and polyphenols, and D. carota had higher ascorbic acid and β‐carotene. The AOA of D. carota leaves, A. paniculatus and P. graveolens almost remained the same at pH 7 and 9. The extracts of D. carota leaves, A. paniculatus and P. graveolens showed increasing AOA after heat treatment. P. granatum was more heat stable than other extracts.PRACTICAL APPLICATIONSRecently, natural plants have received more attention as sources of biologically active substances, including antioxidants, antimutagens and anticarcinogens. Scientific information on the antioxidant properties of various plants that are less widely used in culinary and medicine is scarce. Therefore, six green leafy vegetables (Punica granatum, Ipomoea batatas L., Beta vulgaris, Daucus carota, Amaranthus paniculatus and Peucedanum graveolens) were selected for their antioxidant properties, antioxidant compounds and stability to pH and temperature. P. granatum L. (polyphenol‐rich) can be used in food industries, especially in food systems with varied pH. The extracts proved to be better radical scavengers rather than electron donors (reducing power), which depicts the mechanism through which they act as antioxidants. P. graveolens, A. paniculatus, D. carota and P. granatum, due to their heat stability, can be considered as antioxidants in formulations requiring heat treatment.
STRUCTURAL CHARACTERIZATION AND ANTI‐GLYCATION ACTIVITY IN VITRO OF A WATER‐SOLUBLE POLYSACCHARIDE FROM DENDROBIUM HUOSHANENSE
- Abstract: ABSTRACTA water‐soluble polysaccharide with anti‐glycation activity, designated as DHP‐W2, was isolated and purified from the fresh stems of Dendrobium huoshanense. DHP‐W2 mainly consisted of glucose, xylose, galactose and trace of galacturonic acid, and its average molecular weight was approximately 73 kDa. Methylation analysis and one‐ and two‐dimensional nuclear magnetic resonance (NMR) spectroscopy, including 1H‐NMR, 13C‐NMR, 1H‐1H correlation spectroscopy, heteronuclear single quantum correlation spectroscopy and heteronuclear multiple‐bond correlation spectroscopy, revealed that the repeating units of DHP‐W2 had a backbone consisting of 1,6‐linked β‐D‐Glcp, 1,4‐linked β‐D‐Glcp and 1,4,6‐linked β‐D‐Glcp with branches at O‐4/6. Sugar residues of branches were 1,2,4‐linked α‐D‐Xylp, 1,4‐linked α‐D‐Xylp, 1‐linked α‐D‐Xylp, 1‐linked α‐D‐Galp and 1‐linked α‐D‐GalpA. Preliminary experiment in vitro indicated that DHP‐W2 had an anti‐glycation activity with dose‐ and time‐dependent effects.PRACTICAL APPLICATIONSBecause of potential biological and pharmacological functions, polysaccharides from edible and medicinal plants have gained special attention in the food industry. Dendrobium huoshanense C. Z. Tang and S. J. Cheng, 1984, which is a well‐known edible and medicinal plant belonging to Orchidaceae family, has been used as a tonic to prevent cataractogenesis, throat inflammation and chronic superficial gastritis for centuries in China. This paper reports the structure features of a homogeneous polysaccharide obtained from D. huoshanense and its anti‐glycation activity by a combination of chemical, instrumental and biochemical analysis approaches, including gas chromatography–mass spectrometry (GC‐MS), methylation analysis, Fourier transform infrared, one‐ and two‐dimensional nuclear magnetic resonance spectroscopy, and fluorescence spectrophotometry. The paper's purpose was to provide structural information not only for further elucidation of the relationship between structure and function but also for better understanding of pharmacological mechanism of D. huoshanense polysaccharides. It can be expected to develop the functions of the polysaccharides from D. huoshanense in food industries.
HEAT‐INDUCED CHANGES IN VOLATILES OF MILK AND EFFECTS OF THERMAL PROCESSING ON MICROBIAL METABOLISM OF YOGURT
- Abstract: ABSTRACTFlavor and texture of yogurt are highly associated with the consumer acceptability. The volatiles in the headspace of heated milk and yogurt were analyzed to assess the effects of preheat treatment on microbial metabolism. Seventeen and 25 volatiles were found in fresh raw milk and reconstituted milk using Solid Phase Microextraction‐Gas Chromatography‐Mass Spectrometry, while 23 and 31 volatiles were investigated in their yogurt products, respectively. The levels of aldehydes, methyl ketones, alkanes, olefinic aldehydes and ketenes increased in liquid milk with increasing the intensity of heat treatments. Meanwhile, their levels in respective yogurt showed similar changes. 2‐Pentanone, 2,3‐butanedione and 2,3‐pentanedione that were metabolized by starter culture organisms decreased due to increasing the intensity of heat treatments, suggesting that these heat treatments can inhibit the flavor metabolism of organisms. By analyzing the texture profile of yogurt, hardness, adhesiveness and gumminess increased with increasing the intensity of heat treatments; however, little difference was observed between the raw milk samples and the reconstituted milk samples.PRACTICAL APPLICATIONSThis study demonstrated the differences in flavor impact compounds and textural properties of yogurt due to the preheat treatment and microbial metabolism. Results explain the source of volatile compounds in yogurt processing. Information on the changes in flavor as affected by heating processes would help in understanding their suitability in yogurt production. The research on flavor metabolism would shed light on the final application of some approaches to improve yogurt such as modification of milk medium, screening of the flavor‐producing bacteria and the processing control of flavor production. Also, the finding could be used in the production of flavoring agent.
ERIODICTYOL DECREASES REACTIVE OXYGEN SPECIES PRODUCTION AND INHIBITS P47PHOX CLUSTERING AND TRANSLOCATION IN MONOCYTES
- Abstract: ABSTRACTFlavonoids have been proposed to have anti‐inflammatory activity. Reactive oxygen species (ROS) are important mediators in the inflammatory response. We examined the effects of luteolin, quercetin and eriodictyol on ROS production in phorbol‐12‐myristate‐13‐acetate (PMA)‐stimulated U937 cells. Eriodictyol inhibited ROS production at a lower inhibition concentration 50% (IC50) then luteolin and quercetin (eriodictyol : 0.822 µM, quercetin : 1.134 µM, luteolin : 1.026 µM). Moreover, eriodictyol inhibited ROS production in a dose‐ and time‐dependent manner. Moreover, the p47phox subunit of nicotinamide adenine dinucleotide phosphate oxidase regulated PMA‐mediated ROS production. After eriodictyol treatment, p47phox clustering and translocation also decreased on stimulation of U937 cells with PMA. This study suggests that eriodictyol governs immune responses by modulating p47phox clustering and translocation and ROS production in monocytes – evidence that eriodictyol is an immune regulator of ROS production during inflammatory responses.PRACTICAL APPLICATIONSThis study suggests that eriodictyol governs immune responses by modulating p47phox clustering and translocation and ROS production in monocytes – evidence that eriodictyol is an immune regulator of ROS production during inflammatory responses.
ANTIOXIDANT ACTIVITY OF BENINCASA HISPIDA SEEDS
- Abstract: ABSTRACTOxidative stress induced by free radicals is the main cause of many human diseases. Plant‐derived antioxidant supplements can counter oxidative damage in cells. The purposes of this study were to investigate the effects of water extracts from dried seeds of Benincasa hispida (B. hispida) on antioxidant activity and how this related to total contents of phenolics and flavonoids in vitro. The levels of phenolic and flavonoid compounds were 81.3 ± 1.4 µg gallic acid /g and 486.8 ± 4.1 µg catechin/g dry mass, respectively. B. hispida showed DPPH (2,2‐diphenyl‐picrylhydrazyl hydrate), ABTS (1, 2,2′‐azinobis‐[3‐ethylbenzothiazoline‐6‐sulfonic acid]) and hydroxyl radical scavenging activity in a dose‐dependent manner, with maximum inhibition of 79.8 ± 0.2%, 82.3 ± 1.9% and 95.5 ± 0.8%, respectively. Inhibition of linoleic acid oxidation and nitrite scavenging activity were maximum 73.2 ± 1.0% and 73.6 ± 1.3% at 6 days and 1‐h incubation time, respectively. Our data suggest that the dried seeds from B. hispida could be used as a source of natural antioxidants in the food industry.PRACTICAL APPLICATIONSOther evidence suggests that the consumption of wax gourd promotes health. This is because of several important bioactive compounds such as lipids, protein, carbohydrates, fiber, minerals and vitamins that have already been isolated from wax gourd. Wax gourd is effective against diabetes, dropsy, diseases related to liver, leucorrhea and fever. It can strengthen the function of bladder and small and large intestines. It is also good for the detoxication of minerals. The findings of this study can demonstrate the antioxidant activity of the water extracts from B. hispida dried seeds. The nitrite and free radical scavenging effects of the extract would be useful to improve human health.
PURIFICATION AND CHARACTERIZATION OF SOY COTYLEDON β‐GLUCOSIDASE
- Abstract: ABSTRACTβ‐Glucosidase F42 of soy cotyledons was purified by ammonium sulfate fractionation, ion‐exchange chromatography (CM‐Sephadex‐C‐50, Sigma, St. Louis, MO) and gel filtration (Sephadex G‐100, Sigma). The enzyme was purified 111.8‐fold relative to its concentration in the crude extract. It had an apparent molecular mass of 53 kDa in gel filtration experiments and produced a 33‐kDa band in sodium dodecyl sulfate–polyacrylamide gel electrophoresis, suggesting that it is dimeric. The purified β‐glucosidase F42 was characterized as a glycoprotein after the identification of fucose, galactosamine and glucosamine by high‐pressure anion‐exchange chromatography–pulsed amperometric detector. Its highest activity was observed at pH 5.0 and 45C, and it was stable for up to 4 days at 25C. The Km of the enzyme was 0.12 mM p‐nitrophenyl‐β‐d‐glucopyranoside. β‐Glucosidase F42 showed specificity for different substrates, and its activity was inhibited by 1 mM HgCl2, 10 mM glucono‐δ‐lactone or 150 mM glucose and increased by 10 mM MnCl2.PRACTICAL APPLICATIONSβ‐Glucosidase is an enzyme that hydrolyzes β‐glucosidic bonds to liberate glucose and hydrolyzes isoflavones to release aglycones. Soy aglycones have been broadly investigated because of their biological activity in the prevention and treatment of some chronic diseases. Soy β‐glucosidase can be used in the food industry to alter soy isoflavones for the production of functional foods that are rich in aglycone isoflavones. Therefore, it was an established method of purification of the enzyme that has great biotechnological potential.
EFFECT OF PHENOLIC COMPOUNDS FROM ARGENTINEAN RED WINES ON PATHOGENIC BACTERIA IN A MEAT MODEL SYSTEM
- Abstract: ABSTRACTIn this work, the effectiveness of phenolic compounds of different varieties of wines as antibacterial agent in a meat model system was determined. Total phenolic, flavonoid and flavanol compounds concentrations were greater in Merlot and Malbec wines compared with Cabernet Sauvignon variety. In meat, the best antibacterial effect of wine phenolic compounds against both bacteria was observed with Merlot and Malbec wine varieties at 4C, even when inhibitory effect was also observed at 20C. The lowest decimal reduction time was obtained with Merlot wine for Listeria monocytogenes and with Malbec and Merlot wines for Escherichia coli. From our results, we propose the use of wine phenolic compounds as natural biopreservatives for meat in combination with low temperatures. These natural products provide the additional human health benefit inherent to polyphenols properties.PRACTICAL APPLICATIONSThe exploration of natural antimicrobials for food preservation receives increased attention due to a growing microbial resistance towards conventional preservatives, added to consumer awareness of natural food products. The antibacterial effect of individual phenolic compounds in culture media has been largely studied,, but there is no information about the antibacterial effect of natural combinations of polyphenols from different varieties of wines in meat. In this work, we demonstrate that phenolic compounds combination of Argentinean wines were effective in inhibiting the growth of two pathogenic bacteria that produce food contamination and illness in the consumer. Natural polyphenol combinations found in Argentinean wines could act as natural biopreservatives for meat in combination with low temperatures, achieving extension of the shelf life of food.
ANTIMICROBIAL, ANTIOXIDANT AND FREE RADICAL‐SCAVENGING CAPACITY OF BROWN SEAWEED HIMANTHALIA ELONGATA FROM WESTERN COAST OF IRELAND
- Abstract: ABSTRACTWater, methanol and mixtures (20–80%) thereof have been used for the extraction of phenolic compounds from Irish brown seaweed Himanthalia elongata for studying its antimicrobial and antioxidant properties. The 60% methanolic extract exhibited significantly (P
CHEMICAL COMPOSITION OF THE ESSENTIAL OIL OF MENTHA SPICATA L. FROM TUNISIA AND ITS BIOLOGICAL ACTIVITIES
- Abstract: ABSTRACTIn the present investigation, essential oil (EO) and methanolic extract of Tunisian Mentha spicata leaves were tested for their chemical composition and biological activities. Results showed that EO was characterized by the predominance of oxygenated monoterpenes (92.18%), followed by monoterpene hydrocarbons and sesquiterpenes whose respective amounts were 2.74 and 3.1% of the whole EO. The main volatile compound of M. spicata EO was L‐menthone, accounting for 32.74% of the total volatiles, followed by pulegone (26.67%). The phenolic composition of methanolic extracts was determined by reversed‐phase high‐performance liquid chromatography. The major flavonoid component was apigenin with a mean concentration of 38.4 mg/100 g dry weight. M. spicata leave extract tested for their antioxidant and antibacterial activities showed a significant antiradical and superoxide anion scavenging capacity in addition to the great potential for antimicrobial activities against the bacteria tested.PRACTICAL APPLICATIONSSpearmint (Mentha spicata L.) is an aromatic plant belonging to the Lamiaceae family. M. spicata L. is commercially cultivated in many regions of the world. Spearmint oil has economical importance and is used in perfumery, confectionary and pharmaceutical preparations. Tunisia is blessed with a rich source of aromatic plants, many of which have not been previously investigated for their chemical constituents and biological potentials. Among these plants, we can mention M. spicata L. (Lamiaceae), which is largely distributed from the humid to the upper arid regions. This work was carried out as a first step for a chemical and biological activity of Tunisian M. spicata through phenolic and essential oil composition. A further isolation and purification of M. spicata phenolics and volatiles will be associated with an application in food industry as antioxidants, additives for food preservation and for enhancing their nutritional value and organoleptic quality. Furthermore, a pharmacological study could be established through in vivo assays in order to discover new anticarcenogenic, anti‐inflammatory, antimutagenic and other activities of M. spicata. Such results could be used in pharmaceutical formulations, leading to new human drugs from this medicinal plant.
EFFECT OF COAGULANTS ON ANTIOXIDANT CAPACITY OF MILK PROTEIN CURDS AND THEIR TRYPTIC HYDROLYSATES
- Abstract: ABSTRACTThis study investigated the influences of Ca lactate precipitation, lactic acid coagulation and renneting of proteins in skimmed milk on the physicochemical properties of milk protein powders. Scanning electron micrographs indicated that milk curd from Ca lactate precipitation had the densest network with the smallest protein particles compared with others. It also had the lowest antioxidant capacity: i.e., 0.27 and 0.05 µmol Trolox equivalent (TE)/mg protein, as measured by oxygen radical absorbance capacity–fluorescein (ORACFL) and Trolox equivalent antioxidant capacity (TEAC) assays, respectively (P
EFFECT OF COOKING STYLES ON THE LIPID OXIDATION AND FATTY ACID COMPOSITION OF GRASS CARP (CTENOPHARYNYODON IDELLUS) FILLET
- Abstract: ABSTRACTThe effects of six cooking styles, including boiling, steaming, microwaving, grilling, pan‐frying and deep‐frying, on the lipid oxidation and fatty acid composition of grass carp (Ctenopharyngodon idellus) fillets were investigated. All treatments reduced the moisture contents and increased the relative ratio of protein. Compared with raw samples, the proportions of polar lipid fractions of all samples were increased, while free amino acid contents were significantly decreased. Peroxide values decreased during pan‐frying and deep‐frying, but remained constant in the samples subjected to the other four cooking methods. Microwave baking and grilling increased the p‐anisidine values and resulted in higher lipid oxidative extents. Boiling, steaming, microwave baking and grilling did not affect the fatty acid composition. Pan‐frying and deep‐frying increased the general polyunsaturated fatty acid content and decreased the n–3/n–6 ratio, especially for the deep‐frying cooking method.PRACTICAL APPLICATIONSFish consumption has been linked to health benefits such as reduced risk of coronary heart disease. This is largely attributed to the lipid, cholesterol, fatty acid composition and the polyunsaturated fatty acids present in fish oils. The ω–3 : ω–6 and polyunsaturated fatty acid/saturated fatty acid ratios are considered to be useful criteria for comparing relative nutritional and oxidation values of fish oils. This study was therefore conducted to determine the influence of different cooking styles on the lipid oxidation of grass carp. These features and information are very important to the food health industry because they could be potential guidelines for the clinical, community, foodservice and research dieticians to recommend the proper cooking methods to get better health effects. It is also useful for academic studies on food composition and nutrition.
MODIFICATION OF SERUM AND TISSUE LIPIDS IN RATS FED WITH BLENDED AND INTERESTERIFIED OILS CONTAINING GROUNDNUT OIL WITH LINSEED OIL
- Abstract: ABSTRACTGroundnut oil (GNO) was modified to contain equal proportions of omega‐6/omega‐3 fatty acids by blending with linseed oil. Blended oil (BLE) was subjected to interesterification reaction using immobilized lipase to prepare transesterified oil (TRA). A structured lipid (STR) was also prepared by acidolysis reaction using GNO and omega‐3 fatty acid concentrates from linseed oil. These oils were then fed to rats for a period of 60 days. A reduction in low density lipoprotein cholesterol level by 26 and 23% and a reduction in serum triglyceride concentration by 18.9 and 17.6% were observed in rats given TRA and STR, respectively, as compared with rats fed with GNO. Rats fed with BLE and interesterified oils showed incorporation of α‐linolenic acid and an increase in eicosapentaenoic acid and docosahexaenoic acid in serum and liver lipids. These modified oils could be used for enriching Indian diets with omega‐3 fatty acids.PRACTICAL APPLICATIONSThere is a realization that dietary fat should contain balanced amount of omega‐6 and omega‐3 fatty acids. The oils used in Indian cooking generally contains high amount of omega‐6 but not omega‐3 fatty acids. The present investigation was undertaken to develop oil that can provide equal amounts of omega‐6 and omega‐3 fatty acids by the blending process. The fatty acids in blended oils were randomized through lipase catalyzed acidolysis and transesterification reaction. These modified oils significantly reduced the serum and liver lipids when fed to rats. The modified oils also showed altered physical properties. This study therefore showed that it is possible to restructure the edible oils through biotechnological approaches to get the desired fatty acid composition needed for better nutrition and required physical properties in oils.
ANTIBACTERIAL AND ANTIFUNGAL ACTIVITIES OF BLACK AND GREEN KOMBUCHA TEAS
- Abstract: ABSTRACTKombucha is widely consumed as black tea fermented for 7–14 days. The aim of the present study was to compare the antimicrobial activities of two kombucha beverages originating from green and black teas fermented for 21 days and to characterize the antimicrobial compounds (heat resistance and pH stability). Green and black tea infusions were fermented with a traditional kombucha culture. The resulting kombucha antibacterial/antifungal activities against some pathogenic microorganisms, including human pathogenic bacteria and clinical Candida species, were investigated using the agar diffusion method. The results showed interesting antimicrobial potentials of both experimented kombucha teas against the tested microorganisms, except Candida krusei. The green fermented tea exhibited the highest antimicrobial potential. Indeed, it showed large inhibition zones against Staphylococcus epidermidis (22 mm), Listeria monocytogenes (22 mm) and Micrococcus luteus (21.5 mm). Furthermore, interesting anti‐Candida potential was revealed by the reaction of green tea kombucha against Candida parapsilosis.PRACTICAL APPLICATIONSThe black fermented tea is the original and most popular preparation. This research has focused on the investigation of the antibacterial and antifungal activities of the kombucha prepared from green and black teas against a large number of human pathogens to determine and to compare the potential of the two kombucha drinks. The results showed a broad antimicrobial spectrum of kombucha against a range of pathogenic Candida involved in several candidoses. Moreover, the data showed that the antibacterial potential of kombucha prepared from green tea was higher than that of the original kombucha tea. Considering the antimicrobial activity demonstrated against a wide range of pathogenic bacteria and clinical Candida species, kombucha may be very healthful. As resistance to antimicrobial agents has become increasingly an important global health problem, these findings would be very promising and could be useful as an alternative to current synthetic antimicrobial drugs.
WATER‐SOLUBLE CHITOSAN SENSITIZES APOPTOSIS IN HUMAN LEUKEMIA CELLS VIA THE DOWNREGULATION OF BCL‐2 AND DEPHOSPHORYLATION OF AKT
- Abstract: ABSTRACTChitosan, a natural polysaccharide, has been reported to possess biologically beneficial properties, including antitumor, anti‐inflammatory, antimicrobial and immune‐enhancing effects. However, the precise molecular mechanism of the anticancer activity of chitosan is poorly understood. In this study, we investigated whether water‐soluble chitosan (WSC) has pro‐apoptotic activity on the human leukemia cells (U937, K562, HL60 and THP‐1). Our results showed that treatment with WSC for 24 h inhibited cell proliferation and induced apoptosis in leukemic cells via the mitochondria‐dependent pathway. This effect was accompanied by a marked increase in caspase activation and the cleavage of poly(ADP‐ribose) polymerase. In addition, WSC decreased Bcl‐2 expression in all leukemic cells and reversed the ectopic expression of Bcl‐2 in U937 cells. WSC also suppressed the phosphorylation of Akt, thereby inhibiting cell proliferation. Taken together, these data suggest that WSC inhibits proliferation and induces apoptosis in leukemia cells through the suppression of Bcl‐2‐ and the Akt‐dependent signaling pathways.PRACTICAL APPLICATIONSChitosan is a linear polysaccharide obtained from deacetylated chitin. Usage of this compound is significantly increasing because of its immunomodulating, anticancerous, antibacterial and antiviral activity. However, application of chitosan is limited because chitosan is a weak base and is insoluble in water and organic solvent. Water‐soluble chitosan (WSC) is allowed to be used for more convenient administration and might provide new strategy to prevent cancer growth. These attempts give possibilities for the applications of WSC in economic markets.
LIPID AND FATTY ACID COMPOSITION OF TWO SPECIES OF ABALONE, HALIOTIS DISCUS HANNAI INO AND HALIOTIS DIVERSICOLOR REEVE
- Abstract: ABSTRACTAnalyses of lipid profile and fatty acid compositions of muscle and viscera of two commercially cultured abalone, namely Haliotis discus hannai Ino and Haliotis diversicolor Reeve, have been carried out. The total lipid levels of the viscera of both abalone were much higher than those of muscle. Phospholipids were the predominant lipid components in muscle, whereas triacylglycerol in viscera. The major fatty acids identified in muscle and viscera were C16:0, C18:0, C20:4n–6, C20:5n–3 and C22:5n–3. Polyunsaturated fatty acids (PUFAs) accounted for over 40% of total fatty acids, and C20:4n–6 and C20:5n–3 were the most abundant PUFAs. Moreover, different fatty acid compositions were found between the muscle and viscera. Compared with muscle, viscera contained higher percentage of 4,8,12‐trimethyltridecanoic acid and C18‐PUFA, but lower percentage of C22‐PUFA and dimethyl acetals. This study would increase awareness of the nutritional value of these two abalone and also contribute some important information to abalone aquaculture.PRACTICAL APPLICATIONSHaliotis discus hannai Ino and Haliotis diversicolor Reeve are the main commercially farmed species of abalone and have become the most important species of molluscan mariculture in China and occupied the important position in terms of commercial value among farmed molluscan products. This study analyzed the lipid profile and fatty acid compositions of muscle and viscera of the above two abalone species. The results would provide some useful nutrition information for the consumption and aquaculture of abalone. Meanwhile, the viscera of abalone are rich in total lipids and polyunsaturated fatty acid, indicating that the viscera would have great potential of exploitation and comprehensive utilization in lipids.
IMPROVING THE STABILITY AND RADICAL‐SCAVENGING ACTIVITY OF SUNFLOWER OIL UPON BLENDING WITH BLACK CUMIN (NIGELLA SATIVA) AND CORIANDER (CORIANDRUM SATIVUM) SEED OILS
- Abstract: ABSTRACTBlends (10 and 20%, w/w) of black cumin oil (BCO) and coriander oil (CO) with sunflower oil (SFO) were formulated. Oxidative stability (OS) and radical‐scavenging activity of SFO and blends stored under oxidative conditions (60C) for 15 days were studied. By increasing the proportion of BCO and CO in SFO, linoleic acid content decreased, while oleic acid content increased. Progression of oxidation was followed by measuring peroxide value (PV), conjugated dienes (CDs) and conjugated trienes (CTs). Inverse relationships were noted between PV and OS at termination of storage. Levels of CDs and CTs in SFO and blends increased with an increase in time. SFO : BCO and SFO : CO blends gave 8–18 and 22–32% inhibition of DPPH• radicals, respectively. OS of oil blends was better than SFO, most likely as a consequence of changes in fatty acids' and tocopherols' profile, and minor bioactive lipids found in CO and BCO.PRACTICAL APPLICATIONSBlending of vegetable oil has emerged as an economical way of modifying the physicochemical characteristics of vegetable oils besides enhancement in oxidative stability. Among new sources of vegetable oils, black cumin seed oil (BCO) and coriander seed oil (CO) are of interest and may play a major role in human nutrition and health. At different concentrations of BCO and CO, oxidative stability of high‐linoleic sunflower oil (SFO) was enhanced. Furthermore, blends enriched with BCO and CO had a strong antiradical action. The optimal levels of BCO and CO enrichment will depend on the actual application. It is anticipated that commercial exploitation of SFO : CO and SFO : BCO blends will soon be realized.
ANTIOXIDANT ACTIVITY AND TOTAL PHENOLIC CONTENT OF ORGANICALLY AND CONVENTIONALLY GROWN RICE CULTIVARS UNDER VARYING SEASONS
- Abstract: ABSTRACTThe secondary metabolites of milled rice influenced by agronomic practices, seasons and their interaction effects were investigated. The ethanol extracts of rice grains in two japonica cultivars (Taikeng‐16 and Kaohsiung‐139) were analyzed with different assays to measure the total phenolic content, reducing power, radical‐scavenging activity and chelating activity. Similar to earlier studies of phytochemicals, significantly higher antioxidant values were recorded in the organic rice. Second crop (November/December) in comparison with first crop (June/July) had significantly higher values of antioxidant activities, except for the chelating effect. The interaction between the agronomic practices and seasons had a detrimental effect on the crops because the combined factors had a more significant role than each factor alone. Even with the alterations in their content, polyphenols were positively correlated with the antioxidant activities, with the exception of chelating activity, when considering both factors (agronomic practices and season).PRACTICAL APPLICATIONSOur investigation focused on marketed milled rice which had been underestimated or neglected for the secondary metabolites production in earlier studies. The experiments were conducted on commercially available milled rice for analytical comparison of organically and conventionally grown two japonica rice cultivars for phenolic compounds and antioxidant activities. The result described the positive behavior of milled rice toward the organic farming which enhanced the phytochemicals content and reported higher levels than conventionally grown rice on average. Furthermore, the amounts were higher during winter season as compared with the summer period. The results provide information that the organically grown milled rice could be a potent natural antioxidant to protect against oxidative damage in regular diets while assuring sustainability and food safety.
ENZYMATIC HYDROLYSIS OF PROTEIN FROM SMALL YELLOW CROAKER (PSENDOSCIAENA POLYACTIS) AND EVALUATION OF ITS ANTIOXIDANT ACTIVITY
- Abstract: ABSTRACTEnzymatic hydrolysis of protein from small yellow croaker (Pseudosciaena polyactis) was investigated. Three commercial food grade proteases were used to hydrolyze the small yellow croaker. Among the three hydrolysates, papain hydrolysate exerted the highest scavenging activity against a,a‐diphenyl‐b‐picrylhydrazyl (DPPH) for use in the small yellow croaker hydrolysis. The optimum parameters for hydrolysis using papain were established by the single‐factor and orthogonal test. The optimal hydrolysis conditions were as follows: temperature of 60C, hydrolysis time of 4 h, enzyme concentration of 0.2% and meal/water ratio of 1:5. Under these conditions, the highest degree of hydrolysis (DH) was 49.50%. Antioxidants of protein hydrolysates at 40.96, 43.75, 48.85 and 49.50% of DH were further investigated by DPPH and hydroxyl radical‐scavenging activity. There is a linear parallel relationship between the DHs and the antioxidant properties, and the DH at 49.50% possessed the highest antioxidant activity. The enzymatic hydrolysis of protein from small yellow croaker could be used to produce the hydrolysates possessing antioxidative activities.PRACTICAL APPLICATIONSSmall yellow croaker (Pseudosciaena polyactis), with high production in China, is still underutilized despite the fact that it is rich in high quality protein. Fish protein hydrolysates have been shown to have potential for nutritional or pharmaceutical applications. The aims of this study were to prepare peptides from small yellow croaker (P. polyactis) by enzymatic hydrolysis and to evaluate the antioxidant activity of the resulting hydrolysate. The hydrolysis of protein with proteolytic enzymes can provide more marketable and value‐added food ingredients or industrial products.
A COMPARATIVE STUDY ON THE PHYSICOCHEMICAL, FUNCTIONAL AND PROTEIN ELECTROPHORETIC PATTERN OF OSTRICH MEAT AND BEEF DURING FROZEN STORAGE
- Abstract: ABSTRACTThe interest for new and emerging meats is rapidly growing. Ostrich meat has many nutritional and functional properties that make it superior to other types of meats. The purpose of this research was to evaluate changes in physicochemical and functional properties of ostrich meats (m. iliofibularis) and beef (longissimus dorsi) during storage at −18C. Results showed that Warner–Bratzler shear force values, colorimetric parameters (L*, a*, b*), pH and water‐holding capacity significantly decreased by increasing storage time. Nitrogen solubility index increased after 3 months and decreased thereafter. Buffering capacity, emulsifying capacity, emulsifying stability, foaming stability and cooking loss increased during 6‐month storage. Slight changes in sodium dodecyl sulfate‐polyacrylamide gel electrophoresis pattern of myofibrillar proteins indicate protein denaturation followed by aggregation during prolonged frozen storage. Taken together, within the parameters of the present study, it is concluded that ostrich meat has superior functional attributes compared with beef initially and during the frozen storage.PRACTICAL APPLICATIONSBecause of the superior quality and functional attributes of ostrich meat as compared with beef, the food industry should be aware of possible application of this excellent source of proteins to be included in human nutrition. To achieve this goal, ostrich meat should be evaluated in terms of possible alterations in different quality attributes during various processes, including prolonged frozen storage. In this work, changes in several functional properties of ostrich meat, especially those related to proteins are evaluated.
BIOAVAILABILITY OF DIACYLGLYCEROL MICROEMULSION
- Abstract: ABSTRACTThe bioavailability of diacylglycerol (DAG) microemulsion (DAGM) was investigated in rats. The fatty acid (FA) concentrations in the serum of all rats at 0, 6 and 24h and in feces after oral administration of DAGM and DAG oil were examined. The results showed that the FA concentration of the DAGM group was significantly higher than that of the DAG oil group at 6 h after treatment. The digestibility was detected in rats for 2 weeks. During this period, there was no significant difference in the body weight between the two groups. However, the total food consumption of rats treated with DAGM was evidently less than that treated with DAG oil (P = 0.006). The fat absorption of DAGM was significantly higher than that of DAG oil. The contents of 18:1, 18:2n–6 and 18:3n–3 were significantly lower in the DAGM group than that in the DAG group in fecal lipids. In conclusion, DAGM seems to be a good candidate for enhancing the bioavailability of DAG.PRACTICAL APPLICATIONSWith the advantage of enhancing the bioavailability of active compounds, microemulsion is widely used as a delivery vehicle for actives in pharmaceutics. However, the application of microemulsion technology in common foods has not been prevalent. Diacylglycerol (DAG) oil is an edible and functional oil, the beneficial effects of DAG oil have been shown on both animal and human studies. We have prepared a microemulsion containing DAG oil and investigated the bioavailability of DAGM. Compared with DAG oil, DAGM showed the advantage of high absorption of DAG. The results obtained here could provide a new application of DAG oil in food industry. Furthermore, in the case of achieving the same effect, the excellent absorption implied that DAGM can reduce DAG oil dosage, thereby reducing the economic costs.
POSSIBLE INVOLVEMENT OF OXIDATIVE STRESS IN DIETHYLNITROSAMINE‐INDUCED HEPATOCARCINOGENESIS: CHEMOPREVENTIVE EFFECT OF CURCUMIN
- Abstract: ABSTRACTThis study investigated the effect of curcumin against diethylnitrosamine (DEN)‐induced hepatocarcinogenesis. Rats were divided into three groups. The first group served as a control. The second group received DEN (orally, 20 mg/kg) five times a week for 8 weeks, followed by 10 mg/kg for another 7 weeks. The third group was supplemented with 2% curcumin diet simultaneously with DEN. The results showed normalization of serum level of total antioxidant capacity, γ‐glutamyl transferase and aminotransferase activities along with deoxyribonucleic acid, ribonucleic acid and malondialdehyde levels, glutathione reductase and glutathione peroxidase activities in the liver of curcumin group. Significant decreases in the elevated level of glutathione, glutathione‐S‐transferase and glucose‐6‐P dehydrogenase activities were observed. Serum alkaline phosphatase activity and the relative liver weight were not significantly altered. Concomitantly, the histopathological damage was attenuated by curcumin. In conclusion, curcumin exerted a potential chemopreventive effect in DEN‐induced hepatocarcinogenesis.PRACTICAL APPLICATIONSVarious therapeutic effects, such as anti‐inflammatory, anti‐cancer, anti‐angiogenic and wound‐healing effects, have been described for curcumin. The present study is an endeavor in the direction of determining its possible mechanism of protection in diethylnitrosamine‐induced hepatocarcinogenesis in rats. Our study proved that curcumin exhibits a hepatoprotective potential, and hence, it can be used as value‐added agents to limit both exposure to and the adverse health effects from dietary hepatocarcinogens.
INTESTINAL IMMUNE SYSTEM‐MODULATING ACTIVITY THROUGH PEYER'S PATCH OF FLAVONOID GLYCOSIDE PURIFIED FROM CITRUS UNSHIU PEEL
- Abstract: ABSTRACTAfter methanol extract (CUP‐2) with intestinal immune system‐modulating activity through Peyer's patch was prepared from Citrus unshiu peel, CUP‐2C‐2–2 was purified by solvent partitioning, silica gel 60 and Sephadex LH‐20 chromatographies (Pharmacia Biotech, Uppsala, Sweden). Ultraviolet‐visible spectral, 1H/13C‐NMR, and fast atom bombardment mass spectrometry analyses suggested that CUP‐2C‐2–2 was identified to flavonoid glycoside (5,7,3′,4′‐tetrahydroxyflavone linked by glucose) with molecular weight of 725 Da. When the active chloroform layer (CUP‐2C) fractionated from CUP‐2 was orally administered in mice, the potent activity was observed on the fifth day of 2.0 g/kg body weight/day (1.59‐fold of the saline control). Granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) and interleukin (IL)‐6 contents in the culture medium of Peyer's patch cell were also significantly increased (1.80‐ and 2.20‐fold, respectively) compared with the saline control. These results suggested that flavonoid glycoside from C. unshiu peel might stimulate Peyer's patch and produce the multifunctional hematopoietic growth factors such as GM‐CSF and IL‐6 followed by proliferation of bone marrow cells.PRACTICAL APPLICATIONSC. unshiu peel is widely used as the traditional herbal prescription or tea in East Asia. Since the early 1980s, many researchers have been studying the physiologically active substances from citrus fruit peel for the purpose of exploring their more valuable utilization. Current work is focused on low‐molecular‐weight constituents with intestinal immune system modulating activity through Peyer's patch from citrus peel. It is clearly shown that the purified active substance (CUP‐2C‐2–2) is characterized as flavonoid glycoside. When the active fraction (CUP‐2C) was orally administered in mice, production of hematopoietic growth factors from Peyer's patch cells was stimulated and proliferation of bone marrow cells was induced by these growth factors influxed via systemic circulation. This conclusion supports the rationality of citrus peels as a potential source of biological response modifier for food supplementation or functional foods.
ULTRAFILTRATION PREPARATION OF POTENT BIOACTIVE CORN PEPTIDE AS ALCOHOL METABOLISM STIMULATOR IN VIVO AND STUDY ON ITS MECHANISM OF ACTION
- Abstract: ABSTRACTThe aim of this study was to investigate the potential capability of an alcalase‐hydrolyzed corn protein and fractions with different molecular mass (Mm) to facilitate alcohol metabolism by activating hepatic alcohol dehydrogenase (ADH). Results showed that corn peptide (CP) fraction with Mm fewer than 1,000 Da (CP
ANTIOXIDANT PROPERTIES OF MAJOR FLAVONOIDS AND SUBFRACTIONS OF THE EXTRACT OF PHYLLOSTACHYS PUBESCENS LEAVES
- Abstract: ABSTRACTSix subfractions (H2O eluted fraction, 20% ethanol eluted fraction, 40% ethanol eluted fraction, 60% ethanol eluted fraction, 80% ethanol eluted fraction and acetone fraction) of a 95% ethanol extract of Phyllostachys pubescens leaves were sequentially partitioned by column chromatography (macroporous absorption resin). For the first time, nine specific major flavonoids were isolated from this species. The antioxidant activity levels of these nine major flavonoids and six subfractions were evaluated using a radical‐scavenging assay, including 2,2‐diphenyl‐1‐picrylhydrazyl, hydroxyl radicals and superoxide anion radicals. The total flavonoid content of the six subfractions was determined by colorimetry. Results indicated that the nine major flavonoids and three of the subfractions (20, 40,and 60% ethanol) exhibited powerful antioxidant activity. These three subfractions showed high levels of total flavonoid content. Our results suggest that the nine major flavonoids and three subfractions are promising natural alternatives to synthetic antioxidants as functional food ingredients and natural antioxidant.PRACTICAL APPLICATIONSChinese people realized the medical and health‐promoting effects of bamboo leaves a long time ago. Bamboo and its extracts are used in traditional Chinese medicine and as food additives. Phyllostachys pubescens is a species of bamboo that is widely cultivated in China, primarily for its shoots. Every year, many bamboo leaves are discarded when the shoots are harvested. In this study, major flavonoids and three subfractions made from P. pubescens leaves showed strong antioxidant activity. This capacity was found to be mainly the result of the extracts' high total flavonoid content. These flavonoids and subfractions could be developed into ingredients for use in foods and as natural antioxidant.
CHEMICAL INDICES, ANTIOXIDANT ACTIVITY AND ANTI‐INFLAMMATORY EFFECT OF EXTRACTS OF THE MEDICINAL RICE “NJAVARA” AND STAPLE VARIETIES: A COMPARATIVE STUDY
- Abstract: ABSTRACTChemical indices, antioxidant and anti‐inflammatory activity of extracts of bran of medicinal rice – Njavara “black glumed” type (NBb) and its rice (NBr), were studied in comparison with bran and rice of staple varieties: Sujatha and Palakkadan Matta. Total oryzanol, phenolic, flavonoid, proanthocyanidin and phytate contents of NBb (1.84 mg/g, 27.16 mg of gallic acid/g, 4.50 mg of quercetin/g, 0.98 mg of catechin/g and 8.77 mg/g dry weight of bran, respectively) were higher compared with NBr and staple varieties. NBb showed greater reducing power and significantly higher scavenging activity with 2, 2‐diphenyl‐1‐picryl hydrazyl radical, superoxide and hydrogen peroxide with values of concentration of NBb required to scavenge 50% of respective radicals (IC50): 84.66, 203.16 and 73.55 µg/mL, respectively. The anti‐inflammatory effect (in vivo) of NBb was 83.3%, whereas NBr and staple varieties showed activity in the range 16–66%. The higher oryzanol content, chemical indices, antioxidant and anti‐inflammatory activity for Njavara compared with staple varieties corroborates with its medicinal use in Ayurveda.PRACTICAL APPLICATIONSMedicinal plants are a source of antioxidants and bioactive compounds responsible for the prevention of oxidative stress that leads to many degenerative diseases and conditions. The present study indicates that the extracts of “Njavara” (black glumed), a medicinal rice variety, contains significant amounts of oryzanols, phenolic acids, flavonoids, proanthocyanidins and phytic acid compared with staple varieties. These extracts are potential free radical scavengers and have anti‐inflammatory effect compared with staple varieties. Njavara, identified as a source of bioactive compounds, can be consumed as a health food in addition to its medicinal uses; thus, benefiting consumers. Higher oryzanol content in Njavara is beneficial for lowering plasma cholesterol, reducing platelet aggregation, nerve imbalances and aortic fatty streak formation. Higher antioxidants in Njavara are also beneficial against the diseases initiated by free radicals. These promising results also open up newer areas of research for developing improved varieties of rice containing more bioactive compounds.
THE EFFECT OF KELP ON SERUM LIPIDS OF HYPERLIPIDEMIA IN RATS
- Abstract: ABSTRACTHyperlipidemia is one kind of common and frequently occurring syndromes and closely related to cardiovascular and cerebrovascular disease occurrences in the world. It is significant to explore the marine foods and potential drug resources for the application in treating the hyperlipidemia. We conducted this study to investigate the reducing effect and mechanism of kelp (Saccharina japonica) on serum lipid of rat models with hyperlipidemia induced by a fat‐rich diet. The levels of serum lipid including the triglyceride (TG), total cholesterol (TC), low‐density lipoprotein (LDL) and high‐density lipoprotein (HDL) were detected by biochemical assay. Enzyme‐linked immunosorbent assay was applied to determine the level of oxidized LDL (ox‐LDL). The activity of lipoprotein lipase (LPL) and hepatic lipase (HL) was determined by chemical colorimetry. The concentrations of malondialdehyde (MDA) and nitric oxide (NO) were respectively measured by thiobarbituric acid assay and nitrate reductase assay. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH‐PX) were respectively determined by xanthinoxidase assay and chemical colorimetry. The results showed that the serum levels of TG, TC and LDL decreased, while HDL increased significantly in treated group compared with those of model groups (P
CELLULAR LIPID FATTY ACID PROFILES OF REFERENCE AND FOOD ISOLATES LISTERIA MONOCYTOGENES AS A RESPONSE TO REFRIGERATION AND FREEZING STRESS
- Abstract: ABSTRACTCells of three strains of Listeria monocytogenes, one a reference strain ATCC 19115 and two strains isolated from meat, were cold shocked at refrigeration (+4C) and freezing (−20C) temperatures during one night. Then, their fatty acids were extracted and their composition identified by gas chromatography coupled with mass spectrometry. The results showed that low thermal adaptation response of L. monocytogenes ATCC 19115 was different from that of the two recent food isolates L. monocytogenes. The three experimented strains showed a decrease of anteiso‐C17:0 and an increase of anteiso‐C15:0 rates. In addition, after freezing, the cellular fatty acids were detected as a signature of the membrane changes that give rise to such authenticity. The structural modification seems to be an adaptation form, allowing intracellular ice crystallization enhancement during freezing and water mobility during storage. These results demonstrated that the L. monocytogenes studied strains showed various behaviors regarding low‐temperature stress maintaining membrane fluidity.PRACTICAL APPLICATIONSListeria monocytogenes is prevalent in a variety of foods and ready‐to‐eat products; it may generate a serious public health problem. Nowadays, ready‐to‐eat, chilled and frozen food consumption is continuously increasing. Bacterial strains that can survive at extremely low temperatures adopt special physiological strategies, although the cold‐regulated fatty acid (FA) adjustment is a universal adaptation to low temperatures. To counteract this phenomenon, L. monocytogenes modifies its plasmatic membrane structure to maintain its fluidity at low temperatures, allowing an optimum membrane fluidity that is crucial for bacterial survival. Our study suggested that after freezing, these bacteria underwent several modifications, which are especially critical because they negatively affect bacterial viability and physiological state and induce mechanical damage that leads to cellular death to fight against food invasion with these bacterial species. This work demonstrates the possibility of using membrane FA composition to characterize L. monocytogenes stress‐state as an efficient tool for traceability.
CHARACTERIZATION OF AN ESTERASE ACTIVITY IN LYCOPERDON PYRIFORME, AN EDIBLE MUSHROOM
- Abstract: ABSTRACTAn esterase from Lycoperdon pyriforme was characterized. The enzyme had a maximum activity at pH 8.0 and 40C with p‐nitrophenyl acetate as a substrate. Km and Vmax values were calculated as 2.13 mM and 0.65 U/mg protein, respectively. The enzyme activity was conserved more than 90% over a broad range of pH (3.0–9.0) at 4C after 24 h of incubation. The activity increased 37 ± 3.6% after 120 min of incubation at 40C. Li+, Mg2+ and Ca2+ activated the enzyme 12 ± 1.8, 16 ± 2.5 and 15 ± 2.5%, respectively. The esterase was inhibited in different ratios by some detergents such as Triton X‐114, Triton X‐100, Tween 20 (Sigma Chemical Co., St. Louis, MO) and sodium dodecylsulfate. It retained most of its activity in the presence of methanol and dimethylsulphoxide at the final concentration of 10% (v/v). pH and moderate thermal stability of L. pyriforme esterase and its activity in some organic solvents could make it useful for some industrial purposes such as detergent and paper industry.PRACTICAL APPLICATIONSEsterases play a major role in the degradation of natural materials and industrial pollutants, viz., cereal wastes, plastics and other toxic chemicals. They are also useful in the synthesis of optically pure compounds, perfumes and antioxidants. Because of these biocatalytic applications, it may be interesting to study novel esterases from different organisms. Therefore, it is important to study esterase activity of Lycoperdon pyriforme. In this way, a new esterase having potential applications can be found.
COMPOSITIONAL VARIABILITY OF FUNCTIONAL INGREDIENTS FROM VARIOUS PARTS OF ALPINIA URAIENSIS HAYATA
- Abstract: ABSTRACTThe quantity and antioxidant activity of functional ingredients in various parts of Alpinia uraiensis Hayata were investigated in this study. The ethanolic extracts from the leaves blades, inner cores, petioles, fine roots, stem, outer cores, seeds, rhizomes and main roots of A. uraiensis Hayata were characterized by their antioxidant properties, sugars and high‐performance liquid chromatography (HPLC) analysis. These antioxidant properties and sugars have shown a wide range of variety with significant differences among various plant parts. HPLC chromatogram has also demonstrated that all plant parts contain significantly functional ingredients at absorbance 254 nm with various molecule distribution patterns and quantity. The seeds have the best total phenolics, 2,2‐diphenyl‐1‐picrylhydrazy scavenging activity, total sugar and moderate reducing power activity. This study provides good information of functional ingredients from ethanolic extract of different parts of the A. uraiensis Hayata plant for food and medicinal use.PRACTICAL APPLICATIONSTraditionally, Alpinia used for food and folk medicine is cultivated throughout Asia. There are ample essential oils and antioxidant ingredients in the root, stem, leaf and seed of Zingiberaceous plants. These functional ingredients have been proven to be beneficial to human health. Many diseases can be prevented or ameliorated by compounds or extracts from Alpinia. Therefore, the Alpinia extracts are good candidates for health foods, cosmetic products or even medical uses. The quantity and antioxidant activity of functional ingredients in ethanolic extracts from various parts of A. uraiensis Hayata were characterized in this study. It can provide good reference for product development, especially in agricultural cultivation for mass production of bulk materials, in the health food and cosmetics industries.
EVALUATION OF ANTIOXIDANT AND ANTIMICROBIAL CAPACITY OF SYZYGIUM CUMINI L. LEAVES EXTRACTED SEQUENTIALLY IN DIFFERENT SOLVENTS
- Abstract: ABSTRACTSyzygium cumini is commonly used in India as a traditional medicine. In this study, the antioxidant and antimicrobial potentials of different solvent extracts of S. cumini leaves were investigated. Extraction was done sequentially in Soxhlet apparatus, using various solvents (petroleum ether, toluene, ethyl acetate, acetone and water). Antioxidant activity was evaluated by 2,2‐diphenyl‐1‐picrylhydrazyl free radical scavenging assay, hydroxyl radical scavenging assay, superoxide anion radical scavenging assay and reducing capacity assessment. Total phenol and flavonoid content was also measured. The antimicrobial activity was done by agar well diffusion method against some of the tested foodborne, pathogenic and skin disease causing microorganisms. The acetone extract had more total phenol content and more antioxidant activities, conforming to the hypothesis that phenol content and antioxidant activity has a direct correlation. The acetone extract had notable antimicrobial effect on microorganisms. The results obtained appeared to confirm the antioxidant and antimicrobial potentials of the S. cumini.PRACTICAL APPLICATIONSFood safety is a fundamental concern of both consumers and the food industry, especially as the number of reported cases of food‐associated infections continues to increase. It has been estimated that as many as 30% of people in industrialized countries suffer from foodborne diseases each year. Microorganisms play a major role in contamination of stored foods deteriorating them quantitatively as well as qualitatively. Fungi are significant destroyer of foodstuffs during storage, rendering them unfit for human consumption by retarding their nutritive value and sometimes by producing mycotoxins.In the present study, antioxidant and antimicrobial activities of different solvent extracts of Syzygium cumini leaves was evaluated. Acetone extract had good antioxidant activity comparable with standard and remarkable antimicrobial activity. The results indicate that S. cumini may become important natural source of compounds with health protective potential and antimicrobial agent, which can be used in pharmaceutical, nutraceutical and food preparation.
CHANGES IN PECTIC POLYSACCHARIDES OF CELL‐WALL PREPARATION FROM CHINESE QUINCE FRUIT DURING HEAT TREATMENT
- Abstract: ABSTRACTTo identify suitable conditions for converting pectin covalently (and ionically) attached in the cell wall of Chinese quince (Pseudocydonia sinensis) fruit into water extractable pectins, the cell‐wall preparation (alcohol‐insoluble solids [AIS]) was boiled for up to 4 h in the presence or absence of citric acid (1–4%, w/v). During the heat treatment, the Na2CO3‐soluble and chelator (trans‐1,2‐cyclohexanediaminetetraacetic acid)‐soluble pectin decreased and the water‐soluble pectin increased dramatically. The presence of citric acid accelerated this change, and at higher concentrations, the reaction progressed faster. However, smaller increases in water‐soluble pectin and a remarkable decrease in hemicellulose were observed when the AIS was boiled with 4% citric acid. High‐performance size‐exclusion chromatography analysis revealed that the average molecular weight of polysaccharides in each pectic fraction shifted to lower values during the heat treatment. The best conditions for heat treatment conversion of protopectin to water‐soluble pectin seemed to be under conditions of 1% (w/v) citric acid for 4 h, or 2% (w/v) citric acid for 2 h.PRACTICAL APPLICATIONSChinese quince (Pseudocydonia sinensis) is a medicinal fruit traditionally used in folk medicines and medicinal foods. They are often subjected to heating for a certain time to decompose the cell wall and to obtain a decoction that is rich in medicinal ingredients including pectin. Pectin is a dietary fiber that has many pharmacological properties. The study of the pectin degradation during boiling could reveal the best condition to obtain a decoction containing high amounts of water‐soluble pectin. The optimized condition may be usable when producing a medicinal food from Chinese quince fruit.
EFFECT OF γ‐IRRADIATION ON THE CHEMICAL COMPOSITION AND ANTIOXIDANT PROPERTIES OF CUMIN EXTRACTS
- Abstract: ABSTRACTThe effect of γ‐irradiation on the composition of cumin extracts and also their antioxidant properties were considered. The seeds before and after irradiation (10 and 25 kGy) were subjected to Clevenger extraction to obtain essential oils, and the constituents were identified by gas chromatography–mass spectrometry (GC/MS) analysis. In parallel, the hydroalcoholic extract was used for measuring flavonoid content, free‐radical scavenging (2,2‐diphenylpicrylhydrazyl assay) and antioxidant properties (β‐carotene bleaching test). The results of 10 fractions separated by GC/MS indicated that the total percentage was not affected by γ‐irradiation. γ‐irradiation of cumin seeds also resulted in a nonsignificant change in flavonoid content of the hydroalcoholic extracts. The antioxidant activities of both extract showed potent activities which were not further altered in irradiated samples. These data suggest that γ‐irradiation to cumin seeds is effective for maintaining the composition and antioxidant properties of the seeds.PRACTICAL APPLICATIONSCumin is a traditional plant, originally cultivated in Iran and the Mediterranean region. Cumin is one of the most popular spices in the world widely used as a food flavoring agent. It is also used in Iranian traditional medicine for treatment of different diseases. Considering the contaminations of the seeds by microorganisms, their decontamination by γ‐irradiation seems to be useful. In this study, the compositions and antioxidant activities of the extracts derived from γ‐irradiated cumin seeds in comparison with nonirradiated ones will be achieved.
IRRIGATION REGIMES AND GROWING AREA EFFECTS ON CHÉTOUI OLIVE OIL QUALITY
- Abstract: ABSTRACTThe effects of both the irrigation regimes (50% evapotranspiration [ETc], 75% ETc and 100% ETc) and the growing area on the quality of Chétoui virgin olive oil obtained from an intensively managed orchard in a semi‐arid and arid area with a Mediterranean climate in Tunisia were evaluated. The quality, determined using the usual parameters for virgin olive oils (acidity and peroxide value), was slightly affected by irrigation in the north, and more significatively in the south. Irrigation positively affected fruit weight (86.1% of variability) in all cases. Growing area exhibited a more important effect on the fatty acid profile (96.3% of variability) than the irrigation management (1.8% of variability). Total phenols and bitterness intensity strongly differed: the different irrigation regimes applied in the north had no effect on the bitterness of Chétoui virgin olive oils, whereas the same water management applied in the south caused a marked decrease in both bitterness category and total phenols. Aroma compounds exhibited different behavior according to growing area and irrigation management.PRACTICAL APPLICATIONSThis research is strongly oriented to the agronomic application. The obtained results can orient an agronomist to the suitable irrigation management, applied on the appropriate growing area, in order to obtain a good yield and a balanced composition of the olive oil using the least amount of water.
EXAMINATION OF THE ANTIOXIDANT ACTIVITY OF HABERLEA RHODOPENSIS LEAF EXTRACTS AND THEIR PHENOLIC CONSTITUENTS
- Abstract: ABSTRACTThe present study investigated Haberlea rhodopensis Friv. – a less‐explored Balkan endemic plant. The purpose was to determine the total phenolic content and antioxidant activity of alcohol extracts derived from the leaves of H. rhodopensis Friv. by applying reliable methods. The phenolic concentration in the examined extracts, calculated as mg gallic acid equivalent (GAE)/g leaf dry weight (DW), ranged from 99.03 to 151.24 mg GAE/g DW. The results from the total phenolics assay and the antioxidant activity tests were significantly correlated. The methanol and 70% ethanol extracts, which had the highest total phenolic content values (151.24 and 150.67 mg GAE/g DW, respectively), ranked the highest radical scavenging activity according to the 2,2′‐azino‐bis‐3‐ ethylbenzothiazoline‐6‐sulfonic acid assay (1.451 and 1.343 mMTE/g DW, respectively). The major phenolic acids and some flavonoid aglycones and glycosides were analyzed by high‐performance liquid chromatography. Luteolin (2,706.20 µg/g DW), hesperidin (2,641.46 µg/g DW), sinapic acid (1,296.78 µg/g DW) and ferulic acid (619.80 µg/g DW) were predominant in the H. rhodopensis 70% alcohol extract.PRACTICAL APPLICATIONSThe research yielded novel information about Haberlea rhodopensis, a less‐explored endemic plant. The aim of the present study was to determine the antioxidant capacity of this resurrection plant with a focus on phenolic antioxidants rather than enzymes. High‐performance liquid chromatography analysis was performed to quantify the major phenolic acids and flavonoids. The antioxidant potential of the extracts obtained was estimated using different approved methods. The results suggested the possibility of practical application of H. rhodopensis leaf extracts because of the established free radical‐scavenging activity.