Abstract
This paper aims to make up for the research gap on the interaction between epigallocatechin3-O-(3"-O- methyl) gallate (EGCG3”Me) and alpha-glucosidase (α-glucosidase). Therefore, the interaction between the EGCG3”Me in tea and α-glucosidase was analysed with fluorescence spectrometry to ascertain the binding constants, the number of binding sites and thermodynamic parameters. The results indicate that the binding between EGCG3’’Me and α-glucosidase quenched the internal fluorescent intensity of the latter; the binding constants decreased with the rise of temperature, revealing that the binding ability was alleviated and the fluorescence quenching obeyed the static quenching mechanism; ∆H was negative and ∆S was positive in the binding reaction, signifying that the main interaction forces include the hydrophobic force and hydrogen bonds; the ∆G of the two molecules was negative, an evidence of the spontaneity of the reaction. Combined with the 3D fluorescence spectra changes of α-glucosidase, these results mean that the binding of the molecules was realized through the tryptophan and tyrosine residues in the α-glucosidase. The research proves that the EGCG3”Me in tea is potentially a natural inhibitor of α-glucosidase, and sheds new light on the prevention and treatment of type 2 diabetes.
