[Studies on the interaction between puerarin and bovine serum albumin].

The interaction of puerarin and bovine serum albumin (BSA) under physiological condition was studied by fluorospectrophotometry. The experiment demonstrated that the quenching mechanism of puerarin a BSA was static quenching process. The quenching constant is 7.29 x 10(12) L x mol(-1) x s(-1), and the binding constant is 5.04 x 10(4) L x mol(-1). According to the Forster nonradiative energy transfer theory, the binding distance between donor (BSA) and acceptor (puerarin) was calculated to be 3.35 nm. The influence of the presence of puerarin on structure of BSA was studied by synochronous fluorescence method, the binding distance between BSA and puerarin was also measured, and the binding mechanism was discussed. In addition, the effect of some ions on the binding constant of puerarin with BSA was also studied.