ANTIOXIDANT AND FREE RADICAL SCAVENGING ACTIVITIES OF EDIBLE MUSHROOMS

The antioxidative potency of commercially available mushrooms in Taiwan was studied. The free radical scavenging activities of these mushrooms were demonstrated by using the DPPH method. The antioxidative activities of ethanol extracts of various mushrooms in an emulsified corn oil (o/w) system at 60C were compared. The addition of test compounds in corn oil emulsions significantly extended the induction period of lipid oxidation. The order of inhibitory activity of mushroom extracts on oxidation in emulsion system was Agaricus bisporus > Hypsizigus marmoreus > Volvariella volvacea > Flammulina velutipes > Pleurotus eryngii > Pleurotus ostreatus > Hericium erinaceus > Lentinula edodes. In the thermal oxidative stability test, using lard, the order of antioxidative activity of test materials showed similar tendencies, except for the extract of Lentinula edodes.     

ORGANIC ACID AND SUGAR CONTENTS OF SCUPPERNONG GRAPES DURING RIPENING

Changes in the principal organic acids and sugars of Scuppernong grapes ( V. rotundifolia ) were followed during the ripening season. The vines were sampled bi-weekly during the initial stages of berry development and then weekly as harvest approached until the "overripe" stage was reached. At the ripe stage, malate and tartrate constituted approximately 90% of organic acids with trace quantities of pyruvic, fumaric, succinic, citric and quinic acids. Glucose, fructose and sucrose constituted approximately 90% of the sugars with trace quantities of galactose and maltose. Malate concentration increased during the early stages of ripening, peaked and decreased to a plateau at the ripe stage. Tartrate decreased steadily until it leveled at the ripe stage. Sugars began to accumulate at veraison, increased rapidly thereafter, and leveled at the ripe stage. At harvest, Scuppernong grapes contained 1.60% total acid and 9.45% total sugars on a whole berry basis. Individual constituents were 0.67% malate, 0.92% tartrate, 3.86% fructose, 3.98% glucose, and 1.61% sucrose.     

烘烤对燕麦麸抗氧化物质含量及活性的影响

烘烤处理对燕麦麸抗氧化活性和抗氧化活性物质含量及其在亲水性提取液和亲脂性提取液中分配比的影响.结果表明,燕麦麸抗氧化活性和抗氧化活性物质含量均随烘烤温度、样品水分含量和烘烤时间的增加而下降.烘烤处理后,燕麦麸对过氧化脂质、超氧阴离子和羟自由基的清除能力分别只有原来的36.3%、33.0%和48.8%,总多酚、总黄酮和总皂苷的剩余量分别为原来的68.6%、72.4%和71.9%.     

葡萄及葡萄酒中的有机酸及降酸研究

为了探索降低葡萄酒中过量有机酸的有效方法,综述了葡萄和葡萄酒中有机酸的形成及变化,较系统地论述了国内外葡萄酒降酸研究的进展,着重介绍了本研究室以粟酒裂殖酵母与葡萄酒酵母为亲株,采用原生质体融合技术进行生物降酸的研究。     

肉豆蔻精油抗氧化性能及清除自由基能力的研究

测定肉豆蔻精油(NEO)的总体抗氧化能力、清除超氧阴离子自由基能力、清除羟基自由基能力、抗亚油酸脂质过氧化能力和清除DPPH自由基能力.并与合成抗氧化剂BHT、PG进行比较,对NEO抗氧化和清除游离基活性进行评价.结果表明:NEO具有良好的抗氧化效果,在一定浓度范围内,NEO的抗氧化活性比BHT和PG大,其清除羟自由基、DPPH自由基和超氧阴离子自由基能力优于BHT和PG,但精油抑制亚油酸过氧化能力比BHT和PG略弱.     

TOXICOLOGY AND ANTIOXIDANT ACTIVITIES OF NON-ENZYMATIC BROWNING REACTION PRODUCTS: REVIEW

This article summarizes toxicity and antioxidative activity of non-enzymatic browning reaction products. The subject focuses on the formation and toxicity testing of mutagenic Maillard reaction products (MPRs) formed in food model systems and in actual foods. The MRPs have also been investigated for nutritional, physiological, and biological activities. The antioxidant properties of MRPs are also reviewed in terms of protection potential against oxidative damage associated with a wide variety of diseases such as diabetes and cancer, and pathological conditions such as aging.     

TOXICOLOGY AND ANTIOXIDANT ACTIVITIES OF NON-ENZYMATIC BROWNING REACTION PRODUCTS: REVIEW

This article summarizes toxicity and antioxidative activity of non-enzymatic browning reaction products. The subject focuses on the formation and toxicity testing of mutagenic Maillard reaction products (MPRs) formed in food model systems and in actual foods. The MRPs have also been investigated for nutritional, physiological, and biological activities. The antioxidant properties of MRPs are also reviewed in terms of protection potential against oxidative damage associated with a wide variety of diseases such as diabetes and cancer, and pathological conditions such as aging.     

ANTIOXIDANT AND CALMODULIN-INHIBITORY ACTIVITIES OF PHENOLIC COMPONENTS IN FRUIT WINES AND ITS BIOTECHNOLOGICAL IMPLICATIONS

Fruits are rich sources of anthocyanins, flavonoids and phenols that are important nutraceutical components. Processed products of various fruits such as wines and juices, also contain these nutraceuticals, and have been proposed to be the primary components that provide health-beneficiary effects to the cardiovascular system. In the present study, we have evaluated the antioxidant and calmodulin-inhibitory effects of three fruit wines and a red grape wine to provide a comparison in their nutraceutical properties. Using in vitro systems that generate superoxide radicals and hydroxyl radicals, all the wines and their partially purified phenolic extracts were demonstrated to possess strong superoxide and hydroxyl radical scavenging properties. On the basis of specific phenolic content, the summer cherry, blackberry and blueberry wines were 30–40% more efficient in superoxide radical scavenging than red grape wine. Similarly, blueberry wine demonstrated considerably high hydroxyl radical scavenging efficiency than the other wines. The flavonoid aglycones such as catechin and naringenin, were as efficient or more in scavenging superoxide radicals, as ascorbate. As well, these compounds also scavenged hydroxyl radicals, as or more effectively than melatonin, a known hydroxyl radical scavenger. All the wines had components that inhibited calcium and calmodulin-promoted phosphodiesterase activity, indicating their potential to interfere with the calcium second messenger function. Blueberry, blackberry and red wine components were more effective in the inhibition of calmodulin-promoted phosphodiesterase than those from summer cherry wine. Active oxygen scavenging or calmodulin-inhibitory properties appear to be associated with a variety of wine components that may provide synergistic action than any single components in them. This study paves way for the potential use of fermentation biotechnology to optimize the enzymatic release and levels of nutritionally important phenolic components in fruit wines.     

IN VITRO ANTIOXIDANT AND ANTICANCER ACTIVITIES OF EXTRACTS FROM A FERMENTED FOOD

Solvent extracts were prepared from Manda Enzyme®, one of the fermented health foods, and their activities of radical scavenging and cancer cell growth inhibition were evaluated. Manda Enzyme® was extracted with 55% ethanol, and then fractionated into n‐hexane, chloroform, ethyl acetate, methanol‐soluble and methanol‐insoluble fractions. The antioxidant activities were in the order chloroform > ethyl acetate > other fractions and of each fraction were positively related to the amount of total phenolics and the intensity of brown color. The cancer cell growth inhibitory activities were in the order n‐hexane > chloroform > other fractions. Proliferation of HRT‐18, HCT‐48 and HepG2 human cancer cells was inhibited by the treatment of the n‐hexane fraction of Manda Enzyme® at a concentration of 400 μg/mL to the extent of 75, 89 and 90%, respectively. From these results, it is considered that Manda Enzyme® has chemically different ingredients showing strong antioxidant and anticancer activity in vitro.