芦丁和阿魏酸与酪蛋白的相互作用研究

酚类物质与蛋白质的相互作用对富含酚类物质的功能性乳制品的稳定性及生物活性具有重要影响。通过光谱分析及抗氧化活性测定,研究了芦丁和阿魏酸与酪蛋白的相互作用机制。荧光光谱分析发现,芦丁和阿魏酸均能淬灭酪蛋白的内源荧光,淬灭方式为静态淬灭；热力学参数表明,芦丁与酪蛋白作用的驱动力为疏水作用,阿魏酸与酪蛋白作用的驱动力为疏水作用和氢键。紫外-可见光谱和同步荧光光谱表明,芦丁和阿魏酸的加入影响了酪蛋白中酪氨酸和色氨酸残基周围的微环境,从而引起酪蛋白的构象改变。傅里叶变换红外光谱和圆二色谱研究结果进一步表明,芦丁和阿魏酸使酪蛋白的二级结构发生了变化,但没有破坏其二级结构。

Study on Interaction of Rutin and Ferulic Acid with Casein

Interactions between phenolics and protein play important roles in the stability and bioactivities of functional milks enriched in phenolic compounds. The interaction of rution and ferulic acid with casein were explored by spectroscopic analysis and antioxidant activity assay. Fluorescence spectroscopic analysis indicated that both rutin and ferulic acid could quench intrinsic fluorescence of casein through a static quenching procedure. The results of thermodynamic parameters demonstrated that the binding force of rutin and casein was mainly hydrophobic interaction, while hydrophobic interaction and hydrogen bond were the binding force between ferulic acid and casein. UV-Vis and synchronous fluorescence spectroscopy showed that the addition of rutin and ferulic acid affected the microenvironment around the tyrosine and tryptophan residues in casein, which caused the conformational change of casein. Analysis of fourier transform infrared spectroscopy and circular dichroism further indicated that the secondary structure of casein was changed, but not completely destroyed by rutin and ferulic acid.