Anan Xu , Lin Chen , Yuxuan Shi , Huajie Wang , Qun Ye , Yuefei Wang , Zhonghua Liu , Ping Xu
{"title":"氧化酶和滚动主导红茶多糖缀合物的形成:酶和非酶机制","authors":"Anan Xu , Lin Chen , Yuxuan Shi , Huajie Wang , Qun Ye , Yuefei Wang , Zhonghua Liu , Ping Xu","doi":"10.1016/j.foodchem.2025.145765","DOIUrl":null,"url":null,"abstract":"<div><div>Tea processing significantly contributes to the heterogeneity of tea polysaccharide conjugates; however, the specific mechanisms underlying their formation remain unclear. In the present work, it is found that rolling is the critical stage for the formation of black tea polysaccharide conjugates. In vitro enzymatic reactions demonstrated that oxidases, particularly peroxidase with synergistic support from polyphenol oxidase, mediate conjugate formation. Molecular docking studies further revealed strong interactions between proteins, phenolics, and sugar chain units through hydrogen bonding and hydrophobic forces, with key residues such as LEU-189, ARG-458, and HIS-145 playing pivotal roles. This study elucidates the enzymatic and non-enzymatic mechanisms underlying black tea polysaccharide conjugate formation and provides novel insights for optimizing tea processing to precisely design polysaccharide conjugates.</div></div>","PeriodicalId":318,"journal":{"name":"Food Chemistry","volume":"493 ","pages":"Article 145765"},"PeriodicalIF":9.8000,"publicationDate":"2025-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Oxidases and rolling dominate black tea polysaccharide conjugates formation: Enzymatic and non-enzymatic mechanisms\",\"authors\":\"Anan Xu , Lin Chen , Yuxuan Shi , Huajie Wang , Qun Ye , Yuefei Wang , Zhonghua Liu , Ping Xu\",\"doi\":\"10.1016/j.foodchem.2025.145765\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Tea processing significantly contributes to the heterogeneity of tea polysaccharide conjugates; however, the specific mechanisms underlying their formation remain unclear. In the present work, it is found that rolling is the critical stage for the formation of black tea polysaccharide conjugates. In vitro enzymatic reactions demonstrated that oxidases, particularly peroxidase with synergistic support from polyphenol oxidase, mediate conjugate formation. Molecular docking studies further revealed strong interactions between proteins, phenolics, and sugar chain units through hydrogen bonding and hydrophobic forces, with key residues such as LEU-189, ARG-458, and HIS-145 playing pivotal roles. This study elucidates the enzymatic and non-enzymatic mechanisms underlying black tea polysaccharide conjugate formation and provides novel insights for optimizing tea processing to precisely design polysaccharide conjugates.</div></div>\",\"PeriodicalId\":318,\"journal\":{\"name\":\"Food Chemistry\",\"volume\":\"493 \",\"pages\":\"Article 145765\"},\"PeriodicalIF\":9.8000,\"publicationDate\":\"2025-08-06\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Food Chemistry\",\"FirstCategoryId\":\"97\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S030881462503016X\",\"RegionNum\":1,\"RegionCategory\":\"农林科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CHEMISTRY, APPLIED\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Food Chemistry","FirstCategoryId":"97","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S030881462503016X","RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, APPLIED","Score":null,"Total":0}
Oxidases and rolling dominate black tea polysaccharide conjugates formation: Enzymatic and non-enzymatic mechanisms
Tea processing significantly contributes to the heterogeneity of tea polysaccharide conjugates; however, the specific mechanisms underlying their formation remain unclear. In the present work, it is found that rolling is the critical stage for the formation of black tea polysaccharide conjugates. In vitro enzymatic reactions demonstrated that oxidases, particularly peroxidase with synergistic support from polyphenol oxidase, mediate conjugate formation. Molecular docking studies further revealed strong interactions between proteins, phenolics, and sugar chain units through hydrogen bonding and hydrophobic forces, with key residues such as LEU-189, ARG-458, and HIS-145 playing pivotal roles. This study elucidates the enzymatic and non-enzymatic mechanisms underlying black tea polysaccharide conjugate formation and provides novel insights for optimizing tea processing to precisely design polysaccharide conjugates.
期刊介绍:
Food Chemistry publishes original research papers dealing with the advancement of the chemistry and biochemistry of foods or the analytical methods/ approach used. All papers should focus on the novelty of the research carried out.