几种茶叶生化成分及其抗氧化活性分析

目的:比较白茶与绿茶、红茶生化成分的差异,探讨生化成分与抗氧化活性的关系。方法:以寿眉、安吉白茶及白琳工夫分别为白茶、绿茶、红茶代表,分析茶叶成分,测定茶汤抗氧化活性,并对二者进行相关性分析。结果:总黄酮含量与年份呈正相关关系,而咖啡碱则相对稳定;白茶茶多酚及儿茶素含量均低于绿茶,但其酯型儿茶素所占比重显著高于绿茶,且游离氨基酸、茶氨酸及总黄酮含量也显著高于其他两种茶类;EGC所占比重与酯型儿茶素均与茶汤抗氧化活性有较强的相关性。结论:白茶与其他茶在成分和抗氧化性上均有显著差异;EGCG与抗氧化活性相关性最强。

Analysis on Biochemistry Components and Antioxidant Activities in Several Kinds of Tea

Objective Differences of biochemical components of white tea,green tea and black tea were compared and the relationship between the components and the antioxidant activity were investigated.Method This paper used Shoumei tea,Anji bai tea and Bailin congou as representatives of white tea,green tea and black tea.By the way,we examined and correlated the biochemical components and antioxidant activities of teas.Result The content of flavonoids was positively correlated with the storage year.While,the content of caffeine was relatively stable.The contents of tea polyphenols and catechins in white tea were lower than those in green tea,but the proportion of ester catechins in white tea was higher than that of green tea.By the way,the content of free amino acids,theanine and flavonoids were the highest among three kinds of tea.The proportion of EGC and the content of ester catechins both had significant correlations with the antioxidant activity.Conclusion This study concluded that significant differences in white tea and other tea were both in composition and the antioxidant activity.By the way,there were highly significant correlations between the antioxidant activity and EGCG.