College of Food Science and Technology, Bohai University, Jinzhou 121013, China.
College of Food Science and Technology, Bohai University, Jinzhou 121013, China.
Int J Biol Macromol. 2022 Sep 30;217:701-713. doi: 10.1016/j.ijbiomac.2022.07.088. Epub 2022 Jul 14.
The denaturation of proteins (particularly myosin) due to freezing can lead to the deterioration of Penaeus vannamei. The purpose of this study was to verify the antifreeze protective effects of polyphenols screened by a molecular docking technique, and to explore their interactions with myosin after freezing treatment. It was found that the screened polyphenols could significantly increase the freezing rate and unfreezable water content of shrimp paste. The results of fluorescence spectra indicated that the hesperetin to myosin quenching process included both dynamic and static quenching, and it was primarily bound to myosin through hydrophobic interactions; The quenching of myosin by both dihydroquercetin and mangiferin was static quenching, and they were bound to myosin mainly by hydrogen bonds and van der Waals forces; All three of these polyphenols had only one binding site on myosin. Surface hydrophobicity indicated that all four polyphenols were engaged in non-covalent binding (hydrophobic interactions) with myosin. Infrared spectra demonstrated that the addition of these four polyphenols significantly increased the α-helix content of myosin. They also reduced the myosin particle size, zeta potential, and protein degeneration degree. Scanning electron microscopy revealed that the four polyphenols reduced the degree of aggregation, while more uniformly distributing the myosin particles. These observations provide a basis for the screening of polyphenols and further research into the protective mechanism of polyphenols on frozen myosin.
蛋白质（尤其是肌球蛋白）的变性会导致凡纳滨对虾的恶化。本研究旨在验证通过分子对接技术筛选出的多酚的抗冻保护作用，并探讨它们在冷冻处理后与肌球蛋白的相互作用。结果表明，筛选出的多酚可显著提高虾酱的冻结速率和不可冻结水含量。荧光光谱结果表明，橙皮素与肌球蛋白的猝灭过程包括动态猝灭和静态猝灭，主要通过疏水相互作用结合到肌球蛋白上；二氢槲皮素和芒果苷与肌球蛋白的猝灭均为静态猝灭，主要通过氢键和范德华力结合到肌球蛋白上；这三种多酚在肌球蛋白上只有一个结合位点。表面疏水性表明，这四种多酚都与肌球蛋白发生非共价结合（疏水相互作用）。红外光谱表明，这四种多酚显著增加了肌球蛋白的α-螺旋含量。它们还降低了肌球蛋白的粒径、zeta 电位和蛋白质变性程度。扫描电子显微镜显示，这四种多酚减少了聚集程度，使肌球蛋白颗粒更均匀地分布。这些观察结果为多酚的筛选和进一步研究多酚对冷冻肌球蛋白的保护机制提供了依据。
