荧光光谱法研究原花青素与牛血清白蛋白的相互作用

Studies on the Interaction between Procyanidins and Bovine Serum Albumin by Fluorescence Spectroscopy

在pH=7.40的Tris-HCl缓冲体系中,采用荧光光谱技术研究了原花青素与牛血清白蛋白(BSA)的相互作用。根据295K、303K、310K、315K温度下的猝灭常数,表明原花青素对BSA的荧光猝灭为静态猝灭过程,由热力学参数焓变(△r Hm)和熵变(△rSm)均大于零,推断出原花青素与BSA之间主要靠疏水作用力相结合,自由能变(△r Gm)为负值,表明原花青素与BSA的作用过程是一个自发过程;应用同步荧光光谱考察了原花青素对BSA构象的影响。

The interaction between procyanidins（PC） and bovine serum albumin（BSA） in physiological buffer（pH=7.4） was studied by fluorescence spectroscopy.The quenching constants were obtained at 295 K,303 K,310 K and 315 K.The results indicated that the fluorescence quenching mechanism for BSA through procyanidins binding is likely a static quenching process.The thermodynamic parameters,enthalpy change（△rHm） and entropy change（△rSm）,were calculated to be 38.282 kJ·mol-1,and 215.9656 kJ·mol-1,respectively,which indicated that the interaction of procyanidins with BSA was driven mainly by hydrophobic force.The process of binding was a spontaneous process in which Gibbs free energy change（△rGm） was negative.The effect of procyanidins on the conformation of BSA was analyzed using synchronous fluorescence spectroscopy.