State Key Laboratory of Meat Quality Control and Cultured Meat Development; Jiangsu Collaborative Innovation Center of Meat Production and Processing, Quality and Safety Control, Nanjing Agricultural University, Nanjing 210095, PR China.
J Agric Food Chem. 2023 Jun 28;71(25):9908-9921. doi: 10.1021/acs.jafc.3c01959. Epub 2023 Jun 20.
Protein-flavonoid conjugation is considered to effectively enhance the functionality of proteins, although how different binding modes affect the conformation and antioxidative properties of these conjugates has yet to be revealed. Herein, myofibrillar protein (MP)-luteolin (Lut) conjugates were noncovalently and covalently constructed using equivalent amounts of Lut (10.00, 20.11, and 69.60 μmol/g protein). Fluorescence quenching confirmed that hydrophobic interactions were the main forces in noncovalent MP-Lut conjugates and that the binding was entropy-driven. Liquid chromatography-tandem mass spectrometry results confirmed that Lut could be covalently grafted with MP after alkaline treatment. Proteomics analysis identified that most graft sites were located on the myosin subunits. Intriguingly, in vitro results showed that the antioxidant activity was barely affected by the MP-Lut binding modes. This work provides a theoretical basis for the application of MP-Lut noncovalent/covalent complexes as functional components.
蛋白质-类黄酮缀合被认为能有效地增强蛋白质的功能，尽管不同的结合模式如何影响这些缀合物的构象和抗氧化性质仍有待揭示。本文采用等摩尔量的芦丁（10.00、20.11 和 69.60 μmol/g 蛋白质），通过非共价和共价键分别构建肌原纤维蛋白（MP）-芦丁（Lut）缀合物。荧光猝灭实验证实，非共价 MP-Lut 缀合物中的主要作用力是疏水相互作用，且结合过程是熵驱动的。液质联用结果证实芦丁经碱处理后可以与 MP 发生共价结合。蛋白质组学分析表明，大多数接枝位点位于肌球蛋白亚基上。有趣的是，体外实验结果表明，MP-Lut 的结合模式对其抗氧化活性几乎没有影响。这项工作为将 MP-Lut 非共价/共价复合物作为功能成分的应用提供了理论依据。
