不同种类茶提取物抗氧化活性的研究

目的]为开发新型天然抗氧化剂提供理论依据。方法]分别用水和50%乙醇提取红茶、绿茶、乌龙茶中的抗氧化性物质,并研究其提取物的抗氧化活性。结果]在相同提取条件下,绿茶水提取物和乙醇提取物的茶多酚含量均最高,其次为乌龙茶,红茶的茶多酚含量最低。绿茶提取物的还原能力最强,其次为乌龙茶提取物,红茶提取物的还原能力最差。50%乙醇提取物清除.OH的能力依次为：绿茶〉乌龙茶〉红茶,其脂质体氧化抑制率依次为：红茶〉绿茶〉乌龙茶。不同种类茶叶的提取物均具有较强的还原能力和抑制脂质体氧化及清除Fenton反应产生的羟自由基的作用。结论]茶叶提取物是一种优良的天然抗氧化剂和自由基消除剂,不同品种茶叶的提取物的抗氧化活性不同。

Study on the Antioxidant Activities of Extracts from Different Kinds of Teas

Objective] The aim of the study was to supply theoretical foundation for developing a new type of natural antioxidant.Method] The antioxidant matters were extracted with water and 50% ethanol from black tea,green tea and oolong tea and the antioxidant activities of their extracts were studied.Result] Under the same extraction condition,the contents of tea-polyphenol in both water extracts and ethanol extracts from green tea were highest,that of oolong tea was secondary and that of black tea was lowest.Th...