53 research outputs found

    Total Antioxidant Activity, and Hesperidin, Diosmin, Eriocitrin and Quercetin Contents of Various Lemon Juices

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    Purpose: To investigate 38 natural and 62 branded lemon juices for their total antioxidant activities and flavonoid content.Methods: The ferric reducing antioxidant power was applied to evaluation of antioxidant. Additionally quercetin, eriocitrin, diosmin and hesperidin contents were evaluated by high performance liquid chromatography (HPLC).Results: Total antioxidant activity of the juices ranged from 91.38 ± 0.01 to 526.93 ± 0.12 Όg/ml. The maximum contents of quercetin, hesperidin and eriocitrin 14.83 ± 2.83, 104.84 ± 12.58 and 10.68 ± 2.41 Όg/mL, respectively. The natural juices had diosmin levels as high as 236.18 mL. The limit of detection (LOD) ranged from 0.15 Όg mg-1 for hesperidine to 0.53 Όg ml-1 for diosmin while the limit of quantification (LOQ) ranged from 0.27 Όg mg-1 for hesperidine to 0.93 Όg ml-1 for quercetin.Conclusion: The developed method can also be applied to the determination of related extracts of orange cultivars as well as various extracts of medicinal plants.Keywords: Antioxidant, Flavonoid, Hesperidin, Diosmin, Eriocitrin, Quercetin, Lemon juic

    Comparison of the antioxidant activity and total phenolic contents in some Stachys species

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    The methanolic extracts of the aerial parts of nine Stachys species: S. persica Gmel., S. fruticulosa M. B., S. laxa Boiss. & Buhse., S. inflata Benth., S. turcomanica Trautv., S. subaphylla Rech. F., S. setiferaC. A. Mey., S. byzantina C. Koch and S. trinervis Aitch. & Hemsl. were investigated for their antioxidant activity and total phenolic content using FRAP and Folin-Ciocalteu assays respectively. S. persica Gmel. and S. fruticulosa M. B. had the highest antioxidant activity (61.42 and 62.02 mmol FeII/100g) and total phenolic content (3294.96 and 4450.36 mg gallic acid/100 g) among these nine species. There was a direct correlation between total phenol and antioxidant activity (R2 = 0.9446, p 0.001) which indicates that polyphenols are the main antioxidants

    Anti-Ulcerative Potential of Punica granatum L (Lythraceae) Hydroalcohol Fruit Peel Extract

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    Purpose: To evaluate the antiulcer activities of the methanol extract of pomegranate (Punica granatum L) fruit peel using 80 % ethanol-induced gastric ulcer model in rats.Methods: Male Wistar rats, 175 - 220 g, were fasted for 48 h, but had free access to water. They were randomly divided into nine experimental groups. Ulcer was induced in the rats with 80 % ethanol. The control group animals received the same treatment as those in the test groups except that the extract treatment was replaced by administration of appropriate volume of the dosing vehicle. Histaminereceptor type-2 (H2) blocker, cimetidine (100 mg/kg, i.p.) was used as the reference drug. Oral pretreatment with three different extract doses (25, 50 and 100 mg/kg) was for 15 days, thereafter, ulcer index (UI) and inhibition were calculated.Results: The extract, at 50 mg/kg, of black fruit peel extract produced significant (p < 0.05) protective effect in rats with a preventive index of 65.87 %. Other doses were significantly protective against ethanol-induced gastric ulcer in the rats. On the other hand, north white peel was not effective (50 mg/kg) showed an ulcer index of 49.52 ± 1.99. Histopathological examination of the stomach of the ulcerated animals treated with white peel (50 mg/kg) showed severe erosion of gastric mucosa, submucosal edema and neutrophil infiltration.Conclusion: The study shows indicates the antiulcer properties of the methanol extracts of north white peel, sour summer and black peel (25, 50, 100 mg/kg) of pomegranate. Their antiulcer activity is exerted, possibly, via its high antioxidant activity.Keywords: Anti-inflammatory, Pomegranate, Punica granatum, Peel extrac

    In vitro antifungal activity of various persian cultivars of Punica granatum L. Extracts against Candida species

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    Background: Resistance of Candida species to antifungal agents has potentially serious implications for management of infections. Candida species are now the fourth most common organisms isolated from hospitalized patients. Prevention and control of these infections will require new antimicrobial agents. Plant-derived antifungal agents have always been a source of novel therapeutics. Objectives: The aim of this study was to investigate the antifungal effect of pomegranate peel and pulp extracts against Candida species. Materials and Methods: Pomegranate pulp and peel were dried and powdered separately. The dried powders were extracted using a soxhlet extractor. The antifungal effect of pomegranate peel and pulp extracts were determined in vitro by using the minimum inhibitory concentration (MIC) against five standard species, including Candida albicans (ATCC 10231), Candida parapsilosis (ATCC 22019), Candida tropicalis (ATCC 750), Candida glabrata (PTCC 5297) and Candida krusei (PTCC 5295). Results: Maximum inhibitions were attributed to peel extract of the pomegranate cultivar against Candida species. The greatest antifungal inhibition among the eight different cultivars was observed for sour malas, sour white peel and sour summer extracts respectively, against the five Candida strains. The antifungal activity of pulp extracts against Candida species was somewhat negative. Conclusions: Our work suggested that pomegranate (Punica granatum L.) peel has potential antifungal activity against Candidiasis, and it is an attractive option for the development of new management strategies for candidiasis. ĂƒÂŻĂ‚ÂżĂ‚Âœ 2015, School of Pharmacy, Ahvaz Jundishapur University of Medical Sciences

    Profiling of major fatty acids in different raw and roasted sesame seeds cultivars

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    The aim of this study was to investigate the fatty acids profile of five sesame cultivars including Branching Naz, Darab, Karaj, Dezful and Black sesame and the effect of time and temperature roasting procedure. The seeds oil content varied from 43±0.28 to 47±0.41% with the average content of 44.4±1.87%. Darab and Black sesame cultivar had the highest and lowest oil content respectively. Oleic and linoleic acids were the two-dominant fatty acids in the sesame seed oil about 80 to 85% of the total amount, whereas palmitic and stearic acids were present at 12 to 15%. Moreover, Dazful and Black sesame had the maximum and minimum content of oxidizability value respectively. The results of the present study showed that the fatty acid contents in studied cultivars were steady during different roasting conditions and fatty acid behavior of samples was good fitted with the high temperatures.Key words: Gas chromatography (GC), fatty acid, roasting procedure, sesame seed, stability

    Effect of Roasting on Fatty Acid Profile of Brown and Yellow Varieties of Flaxseed (Linum usitatissimum L)

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    Purpose: To monitor changes in fatty acid profiles of brown and yellow varieties of flaxseeds in the raw and roasted states using gas chromatography (GC).Methods: Samples of flaxseeds were extracted with n-hexane in a Soxhlet apparatus for 8 h. Methylesterification of the samples was performed by methanolic boron trifluoride (BF3-MeOH) method according to American Oil Chemists' Society (AOCS). Fatty acid (FA), analyzed using GC equipped with a split/splitless capillary injector and flame ionization detector (FID).Results: The results indicate that lipid content varied with the type of seed. Seed oil content was 53.31 ± 0.30 and 45.20 ± 0.20 % for roasted and unroasted brown flax, respectively, and 10.25 ± 0.04 % for the yellow type. The yellow and roasted brown type, at 300oC, showed the lowest and highest oil content, respectively. The highest calculated oxidizability (COX) value was found for the unroasted brown type (13.19 ± 0.01 %) whilst the lowest amount was observed for the roasted brown seed at 350oC (12.79 ± 0.01 %). COX value for yellow type was 5.62 ± 0.01 %.Conclusion: This study shows that the fatty acids content of flaxseeds vary with roasting conditions. This is significant because flax seed fatty acid composition influences the applications of the oil.Keywords: Oil, Flaxseed, Roasting, Fatty acid, Linum usitatissimum, Calculated oxidizability valu

    Environmentally induced changes in antioxidant phenolic compounds levels in wild plants

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    [EN] Different adverse environmental conditions cause oxidative stress in plants by generation of reactive oxygen species (ROS). Accordingly, a general response to abiotic stress is the activation of enzymatic and non-enzymatic antioxidant systems. Many phenolic compounds, especially flavonoids, are known antioxidants and efficient ROS scavengers in vitro, but their exact role in plant stress responses in nature is still under debate. The aim of our work is to investigate this role by correlating the degree of environmental stress with phenolic and flavonoid levels in stress-tolerant plants. Total phenolic and antioxidant flavonoid contents were determined in 19 wild species. Meteorological data and plant and soil samples were collected in three successive seasons from four Mediterranean ecosystems: salt marsh, dune, semiarid and gypsum habitats. Changes in phenolic and flavonoid levels were correlated with the environmental conditions of the plants and were found to depend on both the taxonomy and ecology of the investigated species. Despite species-specific differences, principal component analyses of the results established a positive correlation between plant phenolics and several environmental parameters, such as altitude, and those related to water stress: temperature, evapotranspiration, and soil water deficit. The correlation with salt stress was, however, very weak. The joint analysis of all the species showed the lowest phenolic and flavonoid levels in the halophytes from the salt marsh. 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