Tea Research and Extension Station, Taoyuan 32654, Taiwan.
Department of Biotechnology, Ming-Chuan University, Gui-Shan 33343, Taiwan.
Molecules. 2018 Jul 4;23(7):1631. doi: 10.3390/molecules23071631.
Catechin is a flavan-3-ol, a derivative of flavans, with four phenolic hydroxyl groups, which exhibits a wide range of physiological properties. Chromatographic analyses were employed to examine the effects of blue light irradiation on the changes of catechin hydrate in an alkaline condition. In particular, the detection of a superoxide anion radical (O₂•), a reactive oxygen species (ROS), and the inactivation of ()—including a carbapenem-resistant (CRAB)—was investigated during the photoreaction of catechin hydrate. Following basification with blue light irradiation, the transparent solution of catechin hydrate turned yellowish, and a chromogenic catechin dimer was separated and identified as a proanthocyanidin. Adding ascorbic acid during the photolytic treatment of catechin hydrate decreased the dimer formation, suggesting that ascorbic acid can suppress the photosensitive oxidation of catechin. When catechin hydrate was irradiated by blue light in an alkaline solution, O₂• was produced via photosensitized oxidation, enhancing the inactivation of and CRAB. The present findings on the photon-induced oxidation of catechin hydrate provides a safe practice for the inactivation of environmental microorganisms.
儿茶素是一种黄烷-3-醇，是黄烷的衍生物，具有四个酚羟基，表现出广泛的生理特性。色谱分析被用来研究蓝光照射对儿茶素水合物在碱性条件下变化的影响。特别是，在儿茶素水合物的光反应过程中，检测了超氧阴离子自由基 (O₂•)、活性氧物种 (ROS) 和 () 的失活，包括碳青霉烯类耐药 (CRAB)。儿茶素水合物经蓝光照射碱化后，透明溶液变成黄色，分离出显色儿茶素二聚体并鉴定为原花青素。在儿茶素水合物的光解处理中添加抗坏血酸会减少二聚体的形成，表明抗坏血酸可以抑制儿茶素的光敏感氧化。当儿茶素水合物在碱性溶液中被蓝光照射时，通过光致敏氧化产生 O₂•，增强了 和 CRAB 的失活。儿茶素水合物的光诱导氧化的研究结果为环境微生物的灭活提供了安全的实践依据。
