Zhu YF, Chen JJ, Ji XM, Hu X, Ling TJ, Zhang ZZ, Bao GH, Wan XC. Changes of major tea polyphenols and production of four new B-ring fission metabolites of catechins from post-fermented Jing-Wei Fu brick tea.
Food Chem 2015;
170:110-7. [PMID:
25306324 DOI:
10.1016/j.foodchem.2014.08.075]
[Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 08/03/2014] [Accepted: 08/14/2014] [Indexed: 01/16/2023]
Abstract
HPLC analysis of samples from four major fermentation procedures of Jing-Wei Fu brick tea showed that the level of major tea catechins epigallocatechin gallate (EGCG) and epicatechin gallate (ECG) dropped increasingly to about 1/3 in the final product. Phytochemical study of the final product led to the discovery of four new B-ring fission metabolites of catechins (BRFCs) Fuzhuanin C-F (1-4) together with three known BRFCs (5-7), six known catechins (8-13), five simple phenols (14-18), seven flavones and flavone glycosides (19-25), two alkaloids (26, 27), three triterpenoids (28-30) and one steroid (31). The structures were elucidated by spectroscopic methods including 1D and 2D NMR, LC-HR-ESI-MS, IR, and CD spectra. Five compounds (16-18, 28, 29) were reported for the first time in tea. Possible pathways for the degradation of major tea catechins and the generation of BRFCs were also provided.
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