对羟基苯甲酸对β-葡萄糖苷酶的激活效应及其互作关系OA

To investigate the effect of phenolic acids on the activity of β-glucosidase,this study systematically evaluated the activation mechanism of p-hydroxybenzoic acid(PHBA)at varying concentrations(0～0.5 g/L)through circular dichroism spectroscopy and molecular docking,with a focus on enzyme conformational dynamics and molecular interactions.The results showed that PHBA significantly enhanced β-glucosidase activity in a concentration-dependent manner.Secondary structural analysis revealed that the content of α-helix significantly decreased by 52.14%(P<0.05),while β-sheet,β-turn,and random coil structures increased by 90.20%,27.24%,and 50.56%,respectively,at 0.5 g/L PHBA compared to the control group.These structural shifts suggestted that the enzyme's active site might reside within α-helix regions.Fluorescence quenching assays confirmed spontaneous binding between PHBA and β-glucosidase,with one or one class of binding sites identified.Molecular interaction analyses revealed that hydrogen bonding,van der Waals forces,and hydrophobic interactions predominantly stabilized the PHBA-enzyme complex.Molecular dynamics simulations further validated the structural stability of the PHBA-β-glucosidase complex over 100 ns trajectories(RMSD<0.4 nm),confirming PHBA as a potent β-glucosidase activator.This study elucidates the molecular basis of PHBA-driven enzyme activation and provides a theoretical foundation for enhancing β-glucosidase activity in phenolic acid-rich fermented fruit and vegetable products.