There are many polyphenols used for the preservation of fish, but the interaction mechanism between polyphenols and fish protein is rarely reported. In the present study, the interactions between two kinds of polyphenols (chlorogenic acid (CGA) and rosmarinic acid (RA)) and the myosin of grass carp (Ctenopharyngodon idella) were explored using multi-spectroscopic techniques. Both CGA and RA were found to be involved in reducing the intrinsic fluorescence and surface hydrophobicity of myosin and increasing the UV absorption intensity. This indicates that interactions between CGA, RA, and myosin ultimately result in the formation of polyphenol-myosin complexes. The binding process of CGA and RA for the formation of the complex was spontaneous. The main binding forces between RA and myosin are hydrogen bonding and van der Waals forces, whereas hydrophobic interactions were observed between CGA and myosin. The results of circular dichroism (CD) showed that the presence of CGA and RA increased the content of myosin alpha-helix. CGA and RA caused myosin aggregation which reduced the corresponding solution dispersibility. CGA and RA protected the myosin sulfhydryl groups and reduced the degree of their oxidation. Furthermore, the complexes formed by the combination of myosin, CGA, and RA exhibited the strongest synergistic antioxidant properties than any one of them. The findings of the present study provide insights into our understanding of the mechanism of interactions between myosin and polyphenols which could provide information on the application of polyphenols in preserving aquatic products.

有多种用于保护鱼类的多酚，但鲜有报道多酚与鱼蛋白之间的相互作用机理。在本研究中，两种多酚（绿原酸（CGA）和迷迭香酸（RA））与草鱼肌球蛋白（Ctenopharyngodon idella）之间的相互作用）使用多光谱技术进行了探索。发现CGA和RA均参与减少肌球蛋白的固有荧光和表面疏水性并增加UV吸收强度。这表明CGA，RA和肌球蛋白之间的相互作用最终导致多酚-肌球蛋白复合物的形成。CGA和RA结合形成复合物的过程是自发的。RA和肌球蛋白之间的主要结合力是氢键和范德华力，而CGA和肌球蛋白之间则观察到疏水性相互作用。圆二色性（CD）的结果表明，CGA和RA的存在增加了肌球蛋白α-螺旋的含量。CGA和RA导致肌球蛋白聚集，从而降低了相应的溶液分散性。CGA和RA保护肌球蛋白巯基并降低其氧化程度。此外，由肌球蛋白，CGA和RA组合形成的复合物比任何一种都显示出最强的协同抗氧化性能。本研究的发现为我们对肌球蛋白和多酚之间相互作用机理的理解提供了见识，这可以为多酚在保存水产品中的应用提供信息。