绿茶提取物清除单线态氧的作用及抗脂质过氧化效应

Scavenging Action of Green Tea Extracts on Singlet Oxygen and Preventive Effect on Lipid Peroxidation

光敏化剂玫瑰红光照后产生单线态氧（＾１Ｏ２），以Ｎ，Ｎ－二甲基－４－亚硝基苯胺（ＤＭ－ＮＡ）被漂白作用测定＾１Ｏ２的产生及清除。绿茶提取物（ＧＴＥ）可以清除光敏氧化反应系统产生的＾１Ｏ２，在起始阶段作用更显著，随ＧＴＥ浓度增加清除作用加强。新配制的ＧＴＥ溶液清除＾１Ｏ２的效果较陈旧溶液为佳。ＧＴＥ可以防护单线态氧造成的红细胞膜及微粒体脂质过氧化作用，达到一定浓度进可以完全抑制丙二醛的产生。

Singlet oxygen (1O2) produced hy illuminated photosensitizer Rose Bengal was detected by its bleaching effect on N,N-dimethylnitrosoaniline(DMNA). The 1O2 could be scavenged by green tea extracts (GTE) , with the scavenging action being obvious at the early stage of photosensitized oxidation. The higher the concentration of GTE in the photooxidation reaction system, the stronger the 1O2 scavenging action. The scavenging effect of the fresh GTE solution on singlet oxygen was better than that of old solution. The preventive effects of GTE on lipid peroxidation induced by 1O2 in ghosts and microsomal membranes were also observed. Malondialdehyde (MDA) produc-tion was found to be completely inhibited by a high concentration of GTE in the reaction system.