Effect of interaction between catechin and glycated porcine hemoglobin on its antioxidant functional and structural properties
Lili Liu, Jingfang Guo, Zhe Wang, Xu Duan, Xiaodan Zhang, Ying Yu, Kenan Su, Yuting Lu, Tong Wu
Abstract
This study aimed to investigate the interaction between catechins and glycated porcine hemoglobin (G-PHb). The effects of the interaction on the antioxidant function and structural characteristics of the complex (CG-PHb) of catechin and G-PHb were discussed. Porcine hemoglobin (PHb) and G-PHb were used as controls. The solubility, turbidity, emulsifying property, surface hydrophobicity, and oxidation resistance of CG-PHb were studied. The structural characteristics of the CG-PHb were analyzed via UV–visible spectroscopy, fluorescence spectrometry, fourier transform infrared spectroscopy, scanning electron microscope and molecular docking technology. Compared with the control group, these properties of the CG-PHb are significantly improved. The UV absorption peak of CG-PHb had a larger peak and a slight red shift. The fluorescence peak intensity was in the following order: CG-PHb > PHb > G-PHb. The β-sheet content of CG-PHb increased significantly (P < 0.05). Moreover, SEM showed that the structure of CG-PHb had changed. The surface pore structure increased, which facilitated its functional properties. Molecular docking showed that catechin likely interacted with PHb residues HEM-950, PHE-41, GLU-43, ARG-40 and LEU-96. Catechin and PHb formed a more stable complex because of hydrogen bonds. This study can provide new ideas for protein modification research and provide theoretical basis and reference for the property changes of the CG-PHb during food processing.