【摘要】 采用紫外-可见光谱、荧光光谱和傅里叶变换衰减全反射红外光谱等技术,研究在模拟人体生理Ph值条件下,丹参酚酸A(或丹参酚酸B)与胰岛素分子之间的结合作用,以及丹参酚酸A(或丹参酚酸B)对胰岛素二级结构的影响,并考察葡萄糖对它们的影响。实验结果表明,丹参酚酸A和丹参酚酸B均能导致胰岛素内源性荧光静态猝灭;同步荧光和三维荧光谱图表明胰岛素与丹参酚酸A(或丹参酚酸B)结合后,构象没有发生明显变化。红外光谱研究表明,胰岛素与丹参酚酸A(或丹参酚酸B)结合后二级结构发生了一些改变,β-转角和无规则卷曲的相对含量略有增加,α-螺旋和β-折叠没有发生明显改变。葡萄糖的加入会改变丹参酚酸A(或丹参酚酸B)与胰岛素的结合程度,并加剧胰岛素构象变化以及二级结构中α-螺旋相对含量改变,从而影响丹参酚酸A(或丹参酚酸B)-胰岛素体系中胰岛素的生物活性。更多还原

【Abstract】 The interactions of Salvianolic acid A(SAA)and Salvianolic acid B(SAB)with insulin were studied by using fluorescence spectroscopy,UV-vis spectroscopy and ATR-FTIR spectroscopy in simulating physiological condition(pH 7.40).The fluorescence quenching of insulin by SAA and SAB were static quenching process.The results of synchronous fluorescence and three-dimensional fluorescence spectra suggested no obvious conformation changes of insulin after SAA or SAB binding.But ATR-FTIR spectra showed that SAA and SAB could change the secondary structures of insulin,of which β-turns decreased and random coil increased accompanied withα-helices andβ-sheets no clear change.The glucose might influenced the the bioactivity of insulin in the SAA-insulin and SAB-insulin systems by changing the binding constants of SAA(or SAB)with insulin and exacerbating the changes of insulin conformation and relative contents ofα-helices.更多还原