Stopped flow studies how that the binding equilibrium of emodin to bovine serum albumin (BSA) is established within 100 ms. The adsorption max. of these compounds exhibit red shift upon binding and the absorbance enhanced. The fluorescence quenching associated with the binding of these compounds to BSA was used to measure binding constants, and the distance of Trp-212 to the first binding site were calculated, on the basis of the energy transfer between BSA and bound complexes. An allosteric domain model of emodin-BSA complex was postulated.

Key words: ULTRAVIOLET SPECTROPHOTOMETRY, REACTION KINETICS, FLAVONOID, ANTHRAQUINONE P, CATTLE, FLUOROSPECTROPHOTOMETRY, EMODIN, SERUM ALBUMIN