Influence of Dietary Polyphenols on Catalase Activity In Vitro

The study investigated the impact of three prevalent polyphenols—quercetin, ferulic acid, and caffeic acid—on catalase activity. It was determined that all three polyphenols are capable of binding to catalase, resulting in the formation of a stable complex. This finding was corroborated through fluorescence quenching studies and kinetic modeling. At low concentrations, each polyphenol exhibited an activation effect on catalase; however, at concentrations exceeding 100 μM, they began to function as inhibitors. Notably, caffeic acid and ferulic acid were observed to protect the enzyme from operational inactivation, whereas quercetin did not demonstrate this protective effect. The association constants derived from kinetic modeling were compared with those obtained from docking simulations. The results suggest that polyphenols may exert both beneficial and potentially detrimental effects on cellular antioxidant systems, contingent upon their concentration and specific molecular interactions. This highlights the necessity for careful consideration of dosage in any prospective therapeutic applications.