Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Oct 25;71(42):15745-15753.
doi: 10.1021/acs.jafc.3c04571. Epub 2023 Oct 10.

Novel Oxidation Oligomer of Chlorogenic Acid and (-)-Epigallocatechin and Its Quantitative Analysis during the Processing of Keemun Black Tea

Guoping Lai  1   2 , Mingchun Wen  1   2 , Zongde Jiang  1   2 , Feng Zhou  1   2 , Hui-Xia Huo  3 , Mengting Zhu  1   2 , Zisheng Han  4 , Zixin Zhao  1   2 , Chi-Tang Ho  4 , Liang Zhang  1   2
Affiliations

Novel Oxidation Oligomer of Chlorogenic Acid and (-)-Epigallocatechin and Its Quantitative Analysis during the Processing of Keemun Black Tea

Guoping Lai et al. J Agric Food Chem. .

Abstract

Not only do flavan-3-ols participate in the formation of chromogenic oxidation products such as theaflavins, but chlorogenic acid (3-caffeoylquinic acid, CQA) is also involved in the enzymatic oxidation during black tea processing. The critical oxidation product of CQA and (-)-epigallocatechin (EGC) were identified as an adduct containing benzobicyclo[3.2.2]nonenone structure, which was named as the dichlorogeniccatechin (DCGC) oligomer. It was composed of two molecules of CQA and one molecule of EGC. The effects of the initial reactant ratio and reaction time on the generation of DCGC were also analyzed. A high proportion of CQA promoted the production of DCGC, but a high proportion of EGC inhibited the DCGC formation. In addition, the content of DCGC in Keemun black tea during processing was determined. The content of DCGC highly increased after withering but decreased after drying. This study provides a new perspective for the investigation of other oxidation oligomers in black tea.

Keywords: (−)-epigallocatechin; Keemun black tea; chlorogenic acid; chromogenic product; enzymatic oxidation.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

LinkOut - more resources

-