Electrochemical investigation of the inhibition effect of carvacrol on xanthine oxidase activity merging with theoretical studies

One of the key enzymes in purine catabolism is xanthine oxidase (XO), which is widely distributed in human limbs. Due to the excessive activity of XO in the body, hyperuricemia occurs as one of the consequences of uric acid overproduction, which finally leads to gout. In this study, the inhibitory effect of carvacrol on the XO activity was investigated by differential pulse voltammetry (DPV). The results obtained from the experiments strongly overlapped. Therefore, the multivariate curve resolution-alternating least squares (MCR-ALS) method was used to extract valuable information. Analysis of the electrochemical data using MCR-ALS suggested that carvacrol reduces the electrochemical signals of the active centers of XO. The results show that carvacrol can occupy the catalytic centers of enzyme. Also, interaction assays indicated that carvacrol can exert a dose-dependent inhibitory effect on the XO activity. As observed in docking results, carvacrol can penetrate into the active site of XO to interact with some amino acid residues through the formation of hydrogen bonds with Glu 802. In this study, carvacrol proved to have medicinal properties which make it an appropriate dietary adjuvant for prevention and treatment of gout.