ABSTRACT
The interaction of dihydromyricetin (DMY) and bovine serum albumin (BSA) in solution was investigated by fluorescence, synchronous fluorescence, and ultraviolet (UV) spectra. These results revealed that DMY quenches the fluorescence of BSA by forming the DMY–BSA complex. The number of binding sites (n), binding constant (K a ), and thermodynamic parameter (ΔG, ΔH, ΔS) were calculated. The primary binding forces between DMY and BSA were found to be the electrostatic force and hydrophobic interaction. The binding distance (r) between the donor (BSA) and acceptor (DMY) was determined as 3.43 nm based on Förster's theory. The effect of metal ions (Ni2+, K+, Cu2+, and Co2+) on the binding constant of DMY–BSA complex was also investigated. The effect of DMY on the conformation of BSA was analyzed using synchronous fluorescence spectroscopy and UV-Vis absorption spectroscopy.
ACKNOWLEDGMENT
The authors are grateful for financial support from the National Natural Science Foundation of China (Grant Nos. 20776162, 20775092, and 20805058).