Kato T, Harashima T, Moriya N, Kikugawa K, Hiramoto K
School of Pharmacy, Tokyo University of Pharmacy and Life Science, Hachioji, Japan.
Carcinogenesis. 1996 Nov;17(11):2469-76. doi: 10.1093/carcin/17.11.2469.
Generation of the imidazoquinoxaline-type heterocyclic amines in the heated model system composed of glucose/glycine/creatinine in aqueous diethylene glycol was effectively prevented by phenolic antioxidants, butylated hydroxyanisole (BHA), propyl gallate (PG), sesamol, esculetin and epigallocatechin gallate (EGCG) in a dose-dependent manner. Generation of the mutagens in heated-and-dried bonito meat was effectively prevented on pretreatment with EGCG or green tea extract. Electron spin resonance (ESR) studies showed that the heated model mixture of glucose/glycine generated the unstable pyrazine cation radical, and its formation was inhibited by BHA, sesamol and EGCG. ESR-spin trapping studies using 5,5-dimethyl-1-pyrroline N-oxide (DMPO) and N-tert-butyl-alpha-phenylnitrone (PBN) showed that the heated model mixture of glucose/glycine or glucose/glycine/creatinine generated unstable carbon-centred radical(s), and their formation was effectively inhibited by BHA, sesamol and EGCG. It is likely that the unstable free radical Maillard intermediates played an important role in the formation of the imidazoquinoxaline-type heterocyclic amines, and the phenolic antioxidants effectively scavenged the radical species to prevent the mutagen formation.
在由葡萄糖/甘氨酸/肌酐组成的加热的二甘醇水溶液模型体系中，酚类抗氧化剂丁基羟基茴香醚（BHA）、没食子酸丙酯（PG）、芝麻酚、七叶亭和表没食子儿茶素没食子酸酯（EGCG）以剂量依赖的方式有效抑制了咪唑并喹喔啉型杂环胺的生成。用EGCG或绿茶提取物预处理可有效抑制加热干燥的鲣鱼肉中诱变剂的生成。电子自旋共振（ESR）研究表明，葡萄糖/甘氨酸的加热模型混合物会产生不稳定的吡嗪阳离子自由基，而BHA、芝麻酚和EGCG可抑制其形成。使用5,5-二甲基-1-吡咯啉N-氧化物（DMPO）和N-叔丁基-α-苯基硝酮（PBN）进行的ESR自旋捕获研究表明，葡萄糖/甘氨酸或葡萄糖/甘氨酸/肌酐的加热模型混合物会产生不稳定的碳中心自由基，而BHA、芝麻酚和EGCG可有效抑制其形成。不稳定的自由基美拉德中间体可能在咪唑并喹喔啉型杂环胺的形成中起重要作用，酚类抗氧化剂可有效清除自由基以防止诱变剂的形成。
