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利用紫外光谱、荧光光谱、红边激发荧光位移（REES）法、圆二色谱（CD）结合分子模拟技术共同研究了模拟生理条件下杨梅素与牛血清白蛋白（BSA）的相互作用,阐述了相互作用机制.分子模拟结果表明,杨梅素与蛋白在亚结构域II A的疏水腔内结合,主要作用力为疏水作用力和氢键.依据荧光猝灭法判断猝灭机制为静态猝灭,并得到不同温度下药物与蛋白相互作用的结合常数（Ka）及结合位点数（n）,根据热力学参数判断出作用力类型,并且计算出杨梅素与蛋白的结合距离,与分子模拟得到的判定结果基本一致.通过紫外光谱、同步荧光光谱以及REES法获得的信息讨论了相互作用时BSA中色氨酸（Trp）微环境的变化;并利用CD谱的测定结果定量计算了BSA二级结构中α-螺旋含量的变化.“,”The interaction between myricetin and bovine serum albumin（BSA） was investigated by UV absorption spectroscopy,fluorescence spectroscopy,red edge excitation shift（REES） method,circular di-chroism（CD） and molecular modeling together to explore the mechanism of interaction under simulated physiological condition.The result of molecular modeling indicated that myricetin can bind with BSA in the hydrophobic pocket of sub-domain IIA with hydrophobic force and hydrogen bonding as the main acting force.The fluorescence quenching of BSA by myricetin was employed to observe the quenching mechanism that proved to be a static one.Binding constant（Ka） and binding sites（n） at different temperatures were all calculated,respectively.The results of corresponding thermodynamic parameters as well as binding distance between BSA and myricetin were obtained and proved to agree with that from the molecular modeling.The transformation of micro-environment of Trp in BSA was observed by the spectra of UV absorption,syn-chronous fluorescence and REES method,while the spectrum of CD was employed to research the change of the secondary structure of BSA quantitatively through the assay of α-helix.