Oligomerization mechanism of epigallocatechin-3-O-gallate during autoxidation.
Food Chem
; 449: 139186, 2024 Aug 15.
Article
em En
| MEDLINE
| ID: mdl-38574524
ABSTRACT
The autoxidation of tea catechins by dissolved oxygen proceeds in pH-neutral aqueous solutions, and the major products are oligomers. However, the reaction mechanisms have not been clarified. In this study, the autoxidation of (-)-epigallocatechin-3-O-gallate (1) was examined. The autoxidation with ß-cyclodextrin, which includes the A-ring of 1, significantly suppressed oligomer production and increased the formation of products generated by the oxidative cleavage of the B-ring, indicating the participation of the A-ring in the oligomerization. Further, the autoxidation of 1 in the presence of phloroglucinol, a mimic of the catechin A-ring, yielded products via the nucleophilic addition of phloroglucinol to the B-ring quinone of 1. These results indicated that the oxidative A-B ring couplings accounted for the major oligomerization mechanism.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oxirredução
/
Catequina
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article