Direct evidence of interaction of a green tea polyphenol, epigallocatechin gallate, with lipid bilayers by solid-state nuclear magnetic resonance

The interaction of a tea catechin, epigallocatechin gallate (EGCg), with the model membrane of dimyristoylphosphatidylcholine (DMPC) was studied by solidstate 31P and 2H NMR. The 31P chemical shift anisotropy of the DMPC phosphate group decreased on addition of EGCg. The 2H NMR spectrum of [4-2H] EGCg, which is deuterated at the 4-position, in the DMPC liposomes gave deuterium nuclei with much smaller quadrupole splittings than those in the solid phase. These 31P and 2H NMR observations provide direct experimental evidence that the EGCg molecule interacts with the lipid bilayers.