Gut Microbiota as a Novel Tool to Dissect the Complex Structures of Black Tea Polymers

• DOI: 10.1021/acs.jafc.2c00995
• Publication Date: 2022-04-14T14:52:30Z
• Authors: Weixin Wang; Christina Ohland; Christian Jobin; Shengmin Sang
• Keywords: Tannin; Depolymerization

Thearubigins, polymers of tea catechins, account for more than 20% the black polyphenols and have been reported to be active components in tea. However, chemical structures underlying mechanisms regarding how thearubigins, being poorly bioavailable, generate vivo health benefits are still largely unknown. Using germ-free specific pathogen-free husbandry conditions combined with LC/MS-based nontargeted targeted metabolomic analyses, we investigated role intestinal bacteria thearubigin metabolism. Theaflavins theasinensins were identified as major microbial metabolites suggesting that these molecules building units complex thearubigins. To further confirm this, depolymerization was done using menthofuran an acidic condition. Menthofuran-conjugated theaflavins, theasinensins, catechins well their free forms detected degradation products This indicated theaflavins could polymerized through B-type proanthocyanidin linkages. Furthermore, four able urine samples, they can absorbed into circulatory system. combination degradation, metabolomics, our results demonstrate thearubigins metabolized by gut microbiota corresponding bioactive bioavailable smaller molecular metabolites.