School of Materials Science, Bioscience and Biotechnology Area, Japan Advanced Institute of Science and Technology (JAIST), Nomi, Japan.
Research Centre for Bioscience and Nanoscience, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan.
J Sci Food Agric. 2020 May;100(7):3126-3135. doi: 10.1002/jsfa.10347. Epub 2020 Mar 6.
In this work, we investigated the antioxidant and copper chelating abilities of theaflavin, a polyphenol responsible for astringency, color, and sensation in black tea. Using voltammetric techniques, the analyses were conducted with disposable electrochemical printed carbon chips in conjunction with a portable hand-held potentiostat.
Voltammograms of theaflavin showed five separate oxidation peaks, corresponding to the oxidation of five individual functional groups. Electroanalytical data indicated that, after interaction with copper, theaflavin had higher antioxidant potential and was a better copper chelator than epigallocatechin gallate, a major polyphenol present in green tea and a well-known antioxidant. This could be attributed to the extra fused ring and larger number of OH groups in theaflavin.
Our findings introduce another natural compound as a potential nutraceutical in oxidation- and copper-modulated illnesses. This simple and fast approach would also be highly pertinent to the inspection of the health benefits of natural food products. To the best of our knowledge, this is the first report of the electrochemical analysis of Cu (II) chelation with theaflavin. © 2020 Society of Chemical Industry.
在这项工作中，我们研究了茶黄素的抗氧化和铜螯合能力，茶黄素是一种多酚，它使红茶具有涩味、颜色和口感。使用伏安技术，在结合便携式手动电位计的情况下，在一次性电化学印刷碳芯片上进行分析。
茶黄素的伏安图显示了五个单独的氧化峰，对应于五个单独的功能基团的氧化。电化学分析数据表明，与铜相互作用后，茶黄素具有更高的抗氧化潜力，并且是比表没食子儿茶素没食子酸酯（绿茶中存在的主要多酚和一种众所周知的抗氧化剂）更好的铜螯合剂。这可能归因于茶黄素中额外的稠合环和更多的 OH 基团。
我们的研究结果为氧化和铜调节疾病提供了另一种潜在的营养保健品。这种简单快速的方法也非常适用于天然食品健康益处的检查。据我们所知，这是首次报道电化学分析茶黄素与 Cu（II）螯合。© 2020 英国化学学会。
