PDF(Pubmed)
Abstract：
Tea plants have a long cultivation history in the world, but there are few studies on polysaccharides from fresh tea leaves. In this study, tea polysaccharides (TPSs) were isolated from fresh tea leaves. Then, we investigated the characteristics of TPSs during in vitro simulated digestion and fermentation; moreover, the effects of TPSs on gut microbiota were explored. The results revealed that saliva did not significantly affect TPSs\' molecular weight, monosaccharide composition, and reducing sugar content, indicating that TPSs cannot be digested in the oral cavity. However, TPSs were partially decomposed in the gastrointestinal tract after gastric and intestinal digestion, resulting in the release of a small amount of free glucose monosaccharides. Our in vitro fermentation experiments demonstrated that TPSs are degraded by gut microbiota, leading to short-chain fatty acid (SCFA) production and pH reduction. Moreover, TPSs increased the abundance of Bacteroides, Lactobacillus, and Bifidobacterium but reduced that of Escherichia, Shigella, and Enterococcus, demonstrating that TPSs can regulate the gut microbiome. In conclusion, TPSs are partially decomposed by gut microbiota, resulting in the production of SCFAs and the regulation of gut microbiota composition and function. Therefore, TPSs may be used to develop a prebiotic supplement to regulate the gut microbiome and improve host health.
摘要：
茶树在世界上有着悠久的栽培历史,但是对新鲜茶叶中的多糖的研究很少。在这项研究中,从新鲜茶叶中分离茶多糖(TPSs)。然后，我们研究了体外模拟消化和发酵过程中多糖的特性；此外，探讨了TPSs对肠道菌群的影响。结果显示，唾液没有显著影响血小板的分子量，单糖组成，减少糖含量，这表明TPSs不能在口腔中消化。然而,TPSs经胃肠消化后在胃肠道部分分解，导致释放少量的游离葡萄糖单糖。我们的体外发酵实验表明，TPSs被肠道微生物群降解，导致短链脂肪酸（SCFA）生产和pH降低。此外，TPS增加了拟杆菌的丰度，乳酸菌,和双歧杆菌，但减少了埃希氏菌，志贺氏菌,和肠球菌,证明TPS可以调节肠道微生物组。总之,TPS部分被肠道微生物群分解，导致SCFA的产生和肠道菌群组成和功能的调节。因此,TPP可用于开发益生元补充剂以调节肠道微生物组和改善宿主健康。
