Interaction between Tea Catechin and Food Constituents in the Digestive System

摘要

The interaction between tea catechin and various food constituents in the digestive system was investigated. The content of tea catechin was determined by the ferrous tartrate method, and the catechin components were evaluated by HPLC for the supernatant after centrifuging the mixture of tea catechin and a food constituent. An appreciable difference was found in the tea catechin content of mixtures of catechin with milk casein and bovine albumin. A catechin component analysis showed that the contents of (—)- epicatechin gallate (ECg) and (—)-epigallocatechin gallate (EGCg) were low in catechin mixtures with milk casein, 1 bovine albumin and corn starch. A tea catechin solution exhibited its absorption maximum at 274.5 nm in the ultraviolet region. The absorption bands of catechin mixtures with corn starch and milk casein were shifted downfield due to excitation of the η electron, while the mixture with 3 bovine albumin was shifted upfield due to excitation of the π electron; these shifts were respectively coupled with decreased and increased optical density at the absorption maxima.