齐墩果酸与牛血清白蛋白相互作用的光谱研究

Studies on the Interaction of Oleanolic Acid and Bovine Serum Albumin by Spectral Methods

采用荧光光谱、紫外光谱技术研究了齐墩果酸(OA)与牛血清白蛋白(BSA)的相互作用及热力学特征。结果发现,在293K、301K及310K时,OA与BSA结合常数分别为3.30×104、6.22×104和1.04×105 L.mol-1,通过热力学计算得到反应的焓变和熵变。研究表明,OA能使BSA的内源荧光猝灭,并以动态猝灭为主,二者主要靠疏水力结合;同步荧光光谱研究发现OA对BSA的构象几乎没有影响。

The interaction between oleanolic acid（OA） and bovine serum albumin（BSA） and its thermodynamic characteristics were investigated by fluoresecence spectrometry and UV spectroscopy.The results showed that the binding constants were 3.30×104（293 K）,6.22×104（301 K） and 1.04×105 L／5mol-1（310 K）,respectively.The thermodynamic parameters △H was 51.05 kJ／5mol-1.The fluorescence quenching of BSA by OA indicated that the quenching mechanism was a dynamic quenching,and the thermodynamic parameters showed that the interaction of OA and BSA was mainly driven by hydrophobic force.Synchronous spectra of BSA indicated that OA did not affect the conformation of BSA.