摘要
用 ESR 自旋捕集技术和化学发光法研究了茶多酚复合体及(-)-EGCG 在黄嘌呤—黄嘌呤氧化酶系统中产生的 O_2的清除作用,结果表明,它们的清除能力强于 V_E 和 V_C,并随浓度增加而加强,至6×10^(-3)mg/ml 时,清除率达到最高(>97%),以后则随浓度的加大而下降。对于Fenton 反应产生的·OH,在最适浓度(0.043—0.10 mg/ml)范围内清除率可达99%,一般只有4%—20%,在高浓度下甚至还可发生助氧化作用。茶多酚对 PMA 刺激 PMN 引起的细胞呼吸暴发时产生的活性氧自由基,清除效果显著,并具量效关系。本文还对茶多酚复合体及(-)-EGCG 在高浓度下的助氧化作用进行了讨论。
The scavenging effects of tea polyphenol compound and(-)-EGCG onoxygen free radicals were analysed by using spin trapping technique(ESR)and Chemiluminescence(CL)methods.Results showed that tea polyphenolcompound and(-)-EGCG could more effectively scavenge O_2^(?)generated inthe Xanthine-Xanthine Oxidase system than V_E and V_c,and the scaveng-ing effects increased with the increasings of their concentrations,reachingthe best(more than 97%)at the concentration of 0.006 mg/ml.Beyondthis point the scavenging effects decreased with the increasings of theconcentrations.As for·OH produced by Fenton's reaction,tea polyphenolcompound and(-)-EGCG had the best scavenging effect(99%)under theoptimum concentrations of 0.043—0.10 mg/ml,but insignificant scavengingeffects(4%—20%)under the normal condition,and a prooxidative effectunder the condition of high concentration.Results also showed that teapolyphenol compound and(-)-EGCG could effectively scavenge oxygenfree radicals produced by phorbol myristate acetate(PMA)stimulatedpoIymorphonuclear leukocytes(PMN),and had the quantitative effect.Their prooxidative effects under the condition of high concentration werediscussed in this paper.
出处
《茶叶科学》
CAS
CSCD
1992年第1期59-64,共6页
Journal of Tea Science
基金
国家自然科学基金
