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作 者 ：杨跃华，林树祺，孙涛，程后坤

期 刊 ：核农学报 1994年 8卷 04期 页码：0-0

关键词：茶树；特异成分；辐照；自由基；

Keywords:tea, peculiar compositions, radiation, free radical,

摘 要 ：研究了茶树体内特异成分对辐照诱导自由基的作用。结果表明，辐照茶籽内自由基的增长趋势表现为乔木型大叶品种大于灌木型中、小叶品种，１０个品种茶籽内自由基的耗照剂量效应模型为ｙ＝ａｅ（－ｂ／ｘ）。茶树体内儿茶素、茶多酚、黄酮苷、咖啡碱等特异成分与其辐射敏感性及自由基含量变化密切相关。影响辐照茶树体内自由基消长的主要因子是儿茶素，其中（－）－没食子儿茶素没食子酸酯（ＥＧＣＧ）与自由基反应有浓度效应，在低浓度条件下，具有诱发产生自由基的作用，而在高浓度条件下，则有消除自由基的作用

Abstract:Effects of the peculiar compositions in tea plant on free radical s induced by radiationwas investigated.Results showed that the contents of free radicals in aborescence large-leafvarieties were more than that in shrubby middle-small leaf varieties under the same irradia- tion dose.Dose-effect curve for free radical contents in tea varieties could be discribed withan exponential equation y=9.04-5.35/x.The contents of free radical and the radioseusi- tivities were related to the contents of catechin,tea polyphenols,flavone glycoside and caf- feine. Tbe main factor that affected free radical content in tea plant was catechin. Resultsalso showed that there was a quantitative effect between(-)- EGCG and free radical :(-)-EGCG could induce the incrcase of free radical contents in tea at low concentration but scav-enge free radicals at high concentration.

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