Department of Food and Nutrition Science, Ochanomizu University, Tokyo, Japan.
Biosci Biotechnol Biochem. 2021 Apr 24;85(5):1175-1182. doi: 10.1093/bbb/zbab006.
Ergothioneine (ERGO), a thiohistidine betaine, exists in various fungi, plants, and animals. Humans take in ERGO from their diet. ERGO is a strong biological antioxidant, but there are only a limited number of reports about its redox mechanism. The purpose of this study was to clarify the oxidation mechanism of ERGO. Reactions of ERGO with chemical oxidants were performed. The oxidation products of ERGO were analyzed by nuclear magnetic resonance and liquid chromatography-mass spectrometry (LC-MS). The major product of oxidation of ERGO by hydrogen peroxide in physiological conditions was identified as hercynine (histidine betaine). One molecule of ERGO was able to reduce 2 molecules of hydrogen peroxide. Hercynine was found to react with the more potent oxidant hypochlorite. One unstable decomposition product was detected by LC-MS. As a result, a mechanism of oxidation of ERGO, and hence its physiological antioxidant activity, was developed.
ergothioneine (ergo)，一种硫组氨酸甜菜碱，存在于各种真菌、植物和动物中。人类从饮食中摄取 ergo。ergo 是一种强大的生物抗氧化剂，但关于其氧化还原机制的报道却很少。本研究旨在阐明 ergo 的氧化机制。进行了 ergo 与化学氧化剂的反应。通过核磁共振和液相色谱-质谱（lc-ms）分析 ergo 的氧化产物。在生理条件下，过氧化氢氧化 ergo 的主要产物被鉴定为赫曲林（组氨酸甜菜碱）。一个 ergo 分子能够还原 2 个过氧化氢分子。发现赫曲林与更强的氧化剂次氯酸盐反应。通过 lc-ms 检测到一种不稳定的分解产物。因此，开发了 ergo 的氧化机制及其生理抗氧化活性。
