齐墩果酸及衍生物与牛血清白蛋白相互作用的荧光光谱分析

Interaction of oleanolic acid and its derivatives with bovine serum albumin by spectrofluorimetry

通过化学修饰改善齐墩果酸与牛血清白蛋白的相互作用,从而提高两者之间的结合能力。以齐墩果酸为先导物,分别对其C-3位羟基和C-28位的羧基进行修饰,得到4种不同的衍生物,并用IR和~1H NMR进行结构表征。采用荧光光谱法,研究了齐墩果酸及4种衍生物与牛血清白蛋白的相互作用规律,以及温度和Cu^(2+),Co^(2+)等金属离子对两者之间的相互作用的影响。与齐墩果酸相比,4种衍生物与牛血清白蛋白的相互作用都有提高,其中衍生物OA_2与牛血清白蛋白的相互作用提高了近16倍。Cu^(2+)和Co^(2+)等金属离子能明显增强衍生物OA_2与牛血清白蛋白间的相互作用。化学修饰是提高齐墩果酸与BSA之间的相互作用的有效途径。

Oleanolic acid was chemically modified to improve its interaction with bovine serum albumin,thus to increase the mutual binding ability.As a lead compound,oleanolic acid reacted with Jones-reagent,then methyl iodide and finally hydroxylamine to obtain four different derivatives.Their structures were confirmed by IR and ~1H NMR analysis.The interaction between these derivatives and bovine serum albumin and the effect of temperature and trace metal ions as Cu^2＋and Co^2＋on the interaction were investigated by fluorescence spectroscopy.All these derivatives exhibited improvement of the interaction compared with oleanolic acid with 16 times stronger for OA_2.The interaction also increased with the presence of trace metal ions as Cu^2＋and Co^2＋.These results indicate that chemical modification can improve the interaction of oleanolic acid with bovine serum albumin.