茶儿茶素氧化机理  

Oxidation Mechanism of Tea Catechins

作　　者：李大祥[1] 宛晓春[1] 杨昌军[1] 王华[1] 

机构地区：[1]安徽农业大学农业部教育部茶叶生物化学与生物技术重点开放实验室,合肥230036

出　　处：《天然产物研究与开发》2006年第1期171-181,共11页Natural Product Research and Development

基　　金：安徽省自然科学基金项目(050410304);安徽省教育厅自然科学项目(2005KJ173)

摘　　要：在制茶发酵过程中,儿茶素可发生苯骈环化反应而形成茶黄素,茶黄素还可转化成茶萘酚醒、脱氢茶黄素和高聚合物;同时,儿茶素可发生二聚合反应产生原花青素类以及双黄烷醇类等物质;儿茶素还可能与茶没食子素、杨梅甙、阿福豆素、维生素C、茶氨酸发生聚合反应,形成加合物。体外自由基清除实验表明,儿茶素具有优良的抗氧化特性。儿茶素在清除自由基时,自身氧化产生双黄烷醇,也可发生A环的断裂而产生羧酸类物质。Tea leaves are rich in eateehins. In the precessing of tea fermentation, eatechins undergo oxidation to theaflavins which contain one to three benzotropolone skeletons. Theaflavins further tranform to theanaphthoquinone, dehydrotheaflavin and even high molecular products（possible thearubigin）. Catechins can be also polymefized to pmanthecyanidins and bisflavanols. Moreover, eatechins may react with theogallin, myricetin glycosides, afzelechin, aseorbie acid and theanine to form adduet, re- spectively. Catechins possess excellent antioxidative activity. Cateehins can react with the free radicals and transform to bisflavanols or diearboxylie acid by the disruption of ring A.

关 键 词：茶 儿茶素 氧化 茶黄素 茶红素 原花青素 双黄烷醇 

分 类 号：S571.1[农业科学—茶叶生产加工] Q946.841[农业科学—作物学]