基于荧光光谱法研究酪蛋白与茶黄素类的相互作用

A study on interaction mechanism of casein and theaflavins using fluorescence spectrometry

蛋白质和茶多酚是常见的互作体系,本项目旨在通过荧光光谱法研究酪蛋白和茶黄素类的相互作用,并通过不同温度下模型拟合确定其互作机制。结果表明,茶黄素类能够猝灭酪蛋白的自身荧光,猝灭类型为静态猝灭。当茶黄素类浓度为0.028 mg/mL时,在29℃、37℃和45℃温度下,酪蛋白的荧光强度分别下降了66.7%、55.6%、52.2%,且最大发射波长有轻微红移现象。在不同的温度下,酪蛋白均可自发地与茶黄素类结合,结合位点数约为1,结合方式主要以氢键和范德华力为主导。研究结果可为酪蛋白-茶黄素类复合物在功能食品中的应用提供参考。

Protein and tea polyphenols are common interaction systems.The purpose of this study is to investigate the interaction between casein and theaflavins by fluorescence spectroscopy,and to determine their binding mechanism by model fitting at different temperatures.The results showed that theaflavins could quench the self-fluorescence of casein,and the fluorescence was static.When the concentration of theaflavins was 0.028 mg/mL,the fluorescence intensity of casein decreased by 66.7%,55.6%and 52.2%at 29℃,37℃and 45℃,respectively,and the maximum emission wavelength showed a slight redshift.At different temperatures,casein can spontaneously bind to theaflavins,the number of binding sites is about 1,and the binding mode is mainly dominated by hydrogen bond and van der Waals force.The results provide a foundation for the application of casein-theaflavins complex in functional food.