Puerins A and B, Two New 8-C Substituted Flavan-3-ols from Pu-er Tea

Zhi-Hong Zhou, Ying-Jun Zhang,* Min Xu, and Chong-Ren Yang
State Key Laboratory of Phytochemistry and Plant Resources of West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, People's Republic of China
J. Agric. Food Chem., 2005, 53 (22), pp 8614–8617
DOI: 10.1021/jf051390h
Publication Date (Web): September 24, 2005
Copyright © 2005 American Chemical Society
*

 To whom correspondence should be addressed. Telephone:  +86-871-5223235. Fax:  +86-871-5150124. E-mail:  zhangyj@mail.kib.ac.cn.

Abstract

Pu-er tea is a special treated fermented tea produced from crude green tea, which is prepared from the leaves of Camellia sinensis var. assamica. It is a traditional beverage having been used in China, particularly the southern areas, for a long time. Chemical investigation led to the identification of two new 8-C substituted flavan-3-ols, puerins A (1) and B (2), and two known cinchonain-type phenols, epicatechin-[7,8-bc]-4α-(4-hydroxyphenyl)-dihydro-2(3H)-pyranone (3) and cinchonain Ib (4), together with other seven known phenolic compounds, 2,2‘,6,6‘-tetrahydroxydiphenyl (5), (−)-epicatechin-8-C-β-d-glucopyranoside (6), (−)-epicatechin (EC) (7), (−)-epigallocatechin (EGC) (8), (±)-gallocatechin (GC) (9), gallic acid (10), and myricetin (11), in addition to caffeine (12). Their structures were determined by spectroscopic methods. The compounds 1−5, which might be formed in the postfermentative process of Pu-er tea, were isolated from tea and theaceous plants for the first time.

Keywords: Pu-er tea; Camellia sinensis var. assamica; phenolic compounds

View: Full Text HTML | Hi-Res PDF

Tools

History

  • Published In Issue November 02, 2005
  • Received for review June 12, 2005. Revised manuscript received August 22, 2005. Accepted August 22, 2005.

Recommend & Share

Related Content

Other ACS content by these authors: