相同加工原料下的六大茶类体外抗氧化性能比较

以春季茶树碧香早的一芽二叶茶鲜叶为原料,将其固定及分别加工成六大茶类,比较研究了相同加工茶鲜叶及其干茶质量下的六大茶类体外抗氧化性能,以期为茶叶新产品开发及健康消费提供科学依据。结果表明,固定样及六大茶类的还原能力和清除DPPH.、亚硝基、.OH及O2-.的能力均随茶汤浓度的增加而增强；固定样、绿茶、黄茶、黑茶、乌龙茶、白茶以及红茶对DPPH.的IC50依次为0.017、0.019、0.019、0.020、0.021、0.022和0.038mg干茶浸出物/ml,绿茶、固定样、乌龙茶、黑茶、白茶、黄茶和红茶对.OH的IC50依次为1.438、1.695、2.988、4.163、4.606、4.881和6.847mg干茶浸出物/ml,固定样、乌龙茶、黄茶、绿茶、白茶、黑茶和红茶对亚硝基的IC50依次为1.285、1.401、1.514、1.525、1.847、2.146和5.163mg干茶浸出物/ml。说明由相同原料加工而成的六大茶类在浸泡相同质量干茶的条件下,因其加工工艺的不同而在体外抗氧化性能上存在差异,固定样及六大茶类的抗氧化能力大小在总体上呈现不发酵茶(绿茶)＞半发酵茶(乌龙茶)＞全发酵茶(红茶)的趋势,其中以清除DPPH.的效果最好。

Comparison of Antioxidative Activity in Vitro Among Six Kinds of Tea Made from the Same Raw Material

The antioxidative activity in vitro among six kinds of tea and fixed sample with the same dried tea quality made from one bud and two leaves of BiXiangZao in spring were compared in order to provide scientific reference to the developing of new tea products and healthy consumption. The results showed that reducing power and the capacity of removing DPPH free radical、Nitrate free radical、OH free radical and Superoxide anion radical of all samples increased with infusion concentration increasing. The IC50 of Fixed sample、Green tea、Yellow tea、Dark tea、Oolong tea、White tea and Black tea to DPPH. were 0.017、0.019、0.019、0.020、0.021、0.022 and 0.038mg tea extract /ml; The IC50 of Green tea 、Fixed sample、Oolong tea、Dark tea、White tea、Yellow tea and Black tea to .OH were 1.438、1.695、2.988、4.163、4.606、4.881 and 6.847mg tea extract /ml; The IC50 of Fixed sample、