Study on the interaction between dihydromyricetin and bovine serum albumin by spectroscopic techniques

The interaction between dihydromyricetin (DMY) and bovine serum albumin (BSA) was investigated using fluorescence and ultraviolet spectroscopy at different temperatures under imitated physiological conditions. The experimental results revealed that dynamic quenching, static quenching and non-radiation energy transfer led to the fluorescence quenching. The obtained binding constants, binding sites and corresponding thermodynamic parameters at different temperatures indicate that hydrophobic forces play a major role in the interaction of DMY with BSA. According to Fِrster non-radiation energy transfer theory, the binding distance between BSA and DMY was found to be 3.26 nm. Synchronous fluorescence spectroscopy and FT-IR spectra showed the conformation of BSA changed in the presence of DMY. In addition, the effect of some common metal ions Cu2+, Ca2+, Mg2+, and Zn2+ on the binding constant between DMY and BSA was examined.