光谱法研究人面果提取物12b-羟基-去-D-杰氏山竹子素A与牛血清白蛋白的相互作用

Spectroscopic Study on Interaction between 12b-hydroxy-des-D-garcigerrin A and Bovine Serum Albumi

目的研究傣药人面果的提取物12b-羟基-去-D-杰氏山竹子素A与牛血清白蛋白(BSA)之间的相互作用。方法应用紫外光谱法和荧光光谱法测定了12b-羟基-去-D-杰氏山竹子素A与BSA反应的结合平衡常数K、结合位点数n及其相互作用的机理。结果在生理条件下,12b-羟基-去-D-杰氏山竹子素A与BSA作用导致BSA内源荧光猝灭,其猝灭机理为静态猝灭。其结合常数为:Ka=1.37×105L.mol-1,结合位点数为:n=0.95。结论 12b-羟基-去-D-杰氏山竹子素A与牛血清白蛋白具有较强的相互作用,能够结合形成较稳定的缔合物。

Objective To study the interaction between 12b-hydroxy-des-D-garcigerin A and bovine serum albumin by spectrometric methods.Methods The interaction of bovine serum albumin and 12b-hydroxy-des-D-garcigerrin A was studied using fluorescence spectroscopy and UV absorption spectroscopy in the pH 7.43 Tris-HCl buffer system.Results The research of fluorescence spectroscopy showed that these interactions resulted in the endogenous fluorescence quenching of bovine serum albumin,which belonged to a static quenching mechanism.12b-hydroxy-des-D-garcigerrin A could affect the conformation of bovine serum albumin.The quenching rate constant was 2.44×1014 L·mol-1·S-1,the binding constants Ka was 1.37×105 L·mol-1 and the binding sites of the static quenching n was 0.95.Conclusion The result of UV absorption spectroscopy shows that the absorbance of BSA is increased with the increased of the concentration of 12b-hydroxy-des-D-garcigerrin A,and the pH and salt concentration have few effect on UV absorption of bovine serum albumin and 12b-hydroxy-des-D-garcigerrin A.