Molecular interaction of tea polyphenols with phospholipid bilayers and micelles: Structure-activity relationships

This study examined the molecular interactions of tea polyphenols, particularly catechins and theaflavins, with phospholipid-based systems, including liposomes and micelles, to elucidate the underlying mechanisms responsible for the health benefits associated with green and black tea consumption. The results demonstrate that (-)-epicatechin gallate and (-)-epigallocatechin gallate have a higher affinity for liposomes than (-)-epicatechin and (-)-epigallocatechin. This suggests that the presence of a galloyl moiety in these compounds enhances their interactions with lipid bilayers. Among the four theaflavins, theaflavin3-O-gallate exhibited unique interactions with both liposomes and cholic acid micelles. Thearubigins, which are the main components of black tea infusions, have been found to interact with phospholipids, leading to various biological activities, such as inhibition of cholesterol uptake, astringency, increased systemic circulation, and antibacterial and antiviral effects. In conclusion, the polyphenols in tea infusions come into contact with the surface of phospholipids in the cell membranes or micelles, physically changing these assemblies and impacting their subsequent physiological effects.