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Recently, a number of studies on the health benefits associated with natural compounds have been demonstrated. Phenolics in fruits, vegetables, herbs and spices possess potent antioxidant, anti-inflammatory, antimutagenic and anti...
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Recently, a number of studies on the health benefits associated with natural compounds have been demonstrated. Phenolics in fruits, vegetables, herbs and spices possess potent antioxidant, anti-inflammatory, antimutagenic and anticarcinogenic activities. In the present study, the dried fruits of cinnamon were extracted with ethyl acetate, acetone, methanol and water using a Soxhlet extractor. The total phenolics content of the extracts as determined by Folin-Ciocalteu method were found to be the highest in water extract (44.5%) and the lowest in ethyl acetate (14.4%). The antioxidant activity (AA) of the extracts was evaluated through in vitro model systems such as beta -carotene-linoleate, and 1,1-diphenyl-2-picryl hydrazyl (DPPH); the antimutagenicity of these extracts was also assayed against the mutagenicity of sodium azide by Ames test using tester strain of Salmonella typhimurium (TA100) at different concentrations. In both the model systems, the AA of the extracts was found in the order of water > methanol > acetone > ethyl acetate. All the extracts decreased sodium azide mutagenicity in S. typhimurium strain (TA100). At 5000 micro g/plate all the extracts showed strong antimutagenicity. The antimutagenicity of water extract was followed by acetone, methanol and ethyl acetate. The results of the present study indicate that under-utilized and unconventional part of cinnamon is a good source of antioxidant and antimutagenic phenolics..
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Antioxidant properties of individual essential oils from lemon (Citrus limon L.), pink grapefruit (Citrus paradisi L.), coriander (Coriandrum sativum L.), and clove (Caryophyllus aromaticus L.) buds and their mixtures were studied...
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Antioxidant properties of individual essential oils from lemon (Citrus limon L.), pink grapefruit (Citrus paradisi L.), coriander (Coriandrum sativum L.), and clove (Caryophyllus aromaticus L.) buds and their mixtures were studied by capillary gas-liquid chromatography. Antioxidant activity was assessed by oxidation of the aliphatic aldehyde hexanal to the carboxylic acid. The lowest and highest antioxidant activities were exhibited by grapefruit and clove bud essential oils, respectively. Mixtures containing clove bud essential oil also strongly inhibited oxidation of hexanal. Changes in the composition of essential oils and their mixtures in the course of long-term storage in the light were studied. The stability of components of lemon and coriander essential oils in mixtures increased compared to individual essential oils.
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Four culinary-medicinal mushrooms - Agaricus bisporus (Lange) Imbach, Pleurotus eryngii (DC.: Fr.) Quel., R ferulae (DC.: Fr) Quel., and R ostreatus (Jacq.: Fr.) P. Kumm. (gray strain) - were stored at 4 degrees C for 9 days, and ...
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Four culinary-medicinal mushrooms - Agaricus bisporus (Lange) Imbach, Pleurotus eryngii (DC.: Fr.) Quel., R ferulae (DC.: Fr) Quel., and R ostreatus (Jacq.: Fr.) P. Kumm. (gray strain) - were stored at 4 degrees C for 9 days, and the antioxidant properties of their ethanolic extracts were studied. At day 0, four species of mushrooms showed effective antioxidant properties as evidenced by their low EC50 values (less than 3, 9, 6, and 7 mg/mL for antioxidant activity, reducing power, scavenging ability on 1,1-diphenyl-2-picrylhydrazyl radicals, and chelating ability on ferrous ions, respectively). But their antioxidant properties significantly decreased with storage time. At day 6, EC50 values in antioxidant activity, reducing power, scavenging ability, and chelating ability were 3.12-7.35, 9.19-14.59, 3.70-8.08, and 3.99-9.79 mg/mL, respectively. Total phenols were the major antioxidant components in ethanolic extracts (6.71-7.91 mg/g). Based on the results obtained, mushrooms were recommended to store at 4 degrees C for up to 6 days.
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Ubiquinol, the reduced form of coenzyme Q, is known as a lipid antioxidant. Its fully oxidized form, ubiquinone, would theoretically not have this activity. However, we report that ubiquinone-10, the oxidized form of coenzyme Q, d...
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Ubiquinol, the reduced form of coenzyme Q, is known as a lipid antioxidant. Its fully oxidized form, ubiquinone, would theoretically not have this activity. However, we report that ubiquinone-10, the oxidized form of coenzyme Q, demonstrated antioxidant activity in model studies against a lipid-soluble free radical generator, 2,2'-azobis(2,4-dimethylvaleronitrile). This was demonstrated at both 1:100 and 1:1,000 ratios of ubiquinone-10 to lipid (for both methyl linoleate and methyl linolenate). Ubiquinone-10 should therefore not be discounted as a possible antioxidant in more complex systems such as food.
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The effect of different degrees of roasting on the oxidative reaction of coffee bean oil was studied. The oxidation state of oil fractions extracted from coffee beans having different degrees of roasting were assessed both before ...
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The effect of different degrees of roasting on the oxidative reaction of coffee bean oil was studied. The oxidation state of oil fractions extracted from coffee beans having different degrees of roasting were assessed both before and after removal of the lipid-soluble coloured compounds. The stability of coffee oil increased with the degree of roasting, while it decreased as the coloured fractions were removed.
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Response surface methodology was used to investigate the single screw extrusion of apple pomace-defatted soy flour-corn grits blends and the product properties. Five different blends at a level of 0-20% w/w apple pomace were extru...
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Response surface methodology was used to investigate the single screw extrusion of apple pomace-defatted soy flour-corn grits blends and the product properties. Five different blends at a level of 0-20% w/w apple pomace were extrusion cooked with varied barrel and die temperature (100-140?), screw speed (100-200rpm), and feed moisture content (14-20% wet basis). Increasing apple pomace content in the blends significantly (P<0.05) increased the bulk density, the total phenolic content, and the antioxidant activity of the extrudates. The expansion ratio increased with pomace inclusion level of 5% but decreased significantly (P<0.05) at higher levels of pomace inclusion (10-20%). Moisture content had quadratic influence on water absorption and solubility indices. Optimal extrusion cooking conditions most likely to produce apple pomace-enriched extruded snack products were at 140? barrel and die temperature, 20% feed moisture content, and 200rpm screw speed. The results indicated active interaction between apple pomace and starch during expansion process.
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Lutein is known as a strong antioxidant, and anti-free radical agent for the cosmetic and nutraceutical industry. In addition, it has been reported in several publications that lutein is applicable in pharmaceutics, and can reduce...
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Lutein is known as a strong antioxidant, and anti-free radical agent for the cosmetic and nutraceutical industry. In addition, it has been reported in several publications that lutein is applicable in pharmaceutics, and can reduce the risk of ocular diseases, as well as provide protection against cardiovascular diseases and stroke. However, due to lutein's lipophilic property, it is poorly soluble in water, and therefore, has low bioavailability.
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Phenolic content, antioxidant activities and antimicrobial activities of methanolic, ethanolic and ethyl acetate extracts of five different varieties of aonla (Emblica officinalis) fruits as well their powders were evaluated. Tota...
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Phenolic content, antioxidant activities and antimicrobial activities of methanolic, ethanolic and ethyl acetate extracts of five different varieties of aonla (Emblica officinalis) fruits as well their powders were evaluated. Total polyphenolic content in fresh aonla fruit extracts varied from 70.6 to 159.4 mg GAE/g and their EC 50 (effective concentration) values for antioxidant activity ranged from 46.72 to 359.7 mu g/ml. Significant varietal difference were observed in antioxidant activity of the extracts of fresh aonla fruit and powder. Among the variety analyzed, Desi variety exhibited significantly higher TPC (total polyphenol content) and antioxidant activity in fresh as well as dried form in all the extracts. Methanolic extracts of various varieties had maximum TPC and antioxidant activity. Variety NA-7 showed high TPC and antioxidant activity. Almost, similar trend was observed among the extracts of aonla powders for TPC and AOA (antioxidant activity). A high positive correlation coefficient existed between TPC and AOA of different aonla extracts. All the extracts analyzed, exhibited a strong antimicrobial potential against E. coli, Salmonella typhi, Staphylococcus aureus and Candida albicans. This study suggests aonla as potential natural source of antioxidants and antimicrobial agents.
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Grifola frondosa is an edible mushroom currently available in Taiwan. Ethanolic, cold-water and hot-water extracts were prepared and their antioxidant properties were investigated. At 1 mg/mL, G. frondosa T1 and T2 cold-water extr...
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Grifola frondosa is an edible mushroom currently available in Taiwan. Ethanolic, cold-water and hot-water extracts were prepared and their antioxidant properties were investigated. At 1 mg/mL, G. frondosa T1 and T2 cold-water extracts showed high reducing powers of 1.02 and 0.50, respectively. Chelating abilities on ferrous ions of G. frondosa T1 and T2 were higher for cold-water extracts than for ethanolic and hot-water extracts. For the scavenging ability on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, G. frondosa T1 and T2 extracts were effective in the following order: ethanolic > hot-water > cold-water. The G. frondosa hot-water extract showed high scavenging ability on superoxide anions. Total phenols, flavonoids, ascorbic acid and α-tocopherol are the major antioxidant components found in the various G. frondosa extracts. Based on EC_(50) values (<20 mg/mL) obtained, the various extracts from G. frondosa investigated in this study display potent antioxidative properties.
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