【摘要】 用脉冲辐解动态研究技术，分析了由绿茶中提取的儿茶素对氧化型ｄＧＭＰ羟基加合物的电子转移修复效应。结果表明，ｄＧＭＰ中性Ｎ２Ｏ饱和水溶液在儿茶素存在下脉冲辐解后３１０ｍｍｄＧＭＰ－ＯＨ生长明显减慢，儿茶素酚氧自由基逐渐形成，儿茶素对ｄＧＭＰ－ＯＨ的修复速率常数依次是：ＥＧＣＧ为７．２×１０８ｄｍ３ｍｏｌ－１ｓ－１，ＥＧＣ为４．７×１０８ｄｍ３ｍｏｌ－１ｓ－１，ＥＣＧ为５．６×１０８ｄｍ３ｍｏｌ－１ｓ－１，ＥＣ为２．９×１０８ｄｍ３ｍｏｌ－１ｓ－１。更多还原

【Abstract】 The repairing activity of catechins, extracted from China green tea, towards the oxidized hydroxyl radical adduct of dGMP and its reaction mechanism were studied using pulse radiolysis.Upon pulse radiolysis of nitrous oxide saturated aqueous solution of dGMP and catechins, the transient absorption spectra of the hydroxyl adduct of dGMP decayed with the formation of the phenoxyl radicals of catechins and the transient optical absorpiton (310 nm) of dGMP OH held back with the addition of catechins after the electron pulse.From the formation kinetics of the transient optical absorption of the special peak (310 nm), the rate constant of the repairing reaction was determined to be 7.2×10 8dm 3mol -1 s -1 for EGCG, 4.7×10 8 for EGC, 5.6 ×10 8 for ECG and 2.9×10 8 for EC.更多还原