Li X, Hiramoto K, Yoshida M, Kato T, Kikugawa K
School of Pharmacy, Tokyo University of Pharmacy and Life Science, Hachioji, Japan.
Food Chem Toxicol. 1998 Apr;36(4):305-14. doi: 10.1016/s0278-6915(97)00136-1.
Components with DNA breaking activity in soy sauce were investigated. It was found that there were water soluble high molecular weight DNA breaking components in soy sauce. Two DNA breaking components in the ethyl acetate extract of soy sauce were identified as fragrant components, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) and 4-hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3(2H)-furanone (HEMF), in addition to the previously characterized DNA breaking fragrant component 4-hydroxy-5-methyl-3(2H)-furanone (HMF) (Hiramoto et al., 1996b). Characterization of DNA breaking activity of HEMF was performed, and the mechanisms for the breaking were considered. HEMF cleaved the single strands of supercoiled pBR 322 DNA at pH 7.4 dose dependently and time dependently. DNA breaking was inhibited by superoxide dismutase, catalase, hydroxyl radical scavengers, spin trapping agents and metal chelators, and enhanced by Fe(III) ion. Electron spin resonance-spin trapping technique revealed the generation of hydroxyl radical. Hence, active oxygen species derived from interaction of HEMF with metal ions and oxygen participated in the cleavage. HEMF exhibited mutagenicity to Salmonella typhimurium TA100 without metabolic activation and induced micronucleated mouse peripheral reticulocytes.
对酱油中具有DNA断裂活性的成分进行了研究。发现酱油中存在水溶性高分子量DNA断裂成分。酱油乙酸乙酯提取物中的两种DNA断裂成分被鉴定为香味成分，即2,5 - 二甲基 - 4 - 羟基 - 3(2H)-呋喃酮（DMHF）和4 - 羟基 - 2(或5)-乙基 - 5(或2)-甲基 - 3(2H)-呋喃酮（HEMF），此外还有先前已鉴定的具有DNA断裂活性的香味成分4 - 羟基 - 5 - 甲基 - 3(2H)-呋喃酮（HMF）（Hiramoto等人，1996b）。对HEMF的DNA断裂活性进行了表征，并探讨了其断裂机制。HEMF在pH 7.4条件下能剂量依赖性和时间依赖性地切割超螺旋pBR 322 DNA的单链。超氧化物歧化酶、过氧化氢酶、羟基自由基清除剂、自旋捕获剂和金属螯合剂可抑制DNA断裂，而Fe(III)离子可增强DNA断裂。电子自旋共振 - 自旋捕获技术揭示了羟基自由基的产生。因此，HEMF与金属离子和氧相互作用产生的活性氧物种参与了切割过程。HEMF对鼠伤寒沙门氏菌TA100无代谢活化时表现出致突变性，并诱导小鼠外周网织红细胞产生微核。
