Identification and molecular docking of two novel peptides with xanthine oxidase inhibitory activity from Auxis thazard

Auxis thazard meat was hydrolyzed by alkaline protease. Auxis thazard hydrolysate (ATH) obtained was isolated by ultrafiltration, size exclusion chromatography and reversed-phase high-performance liquid chromatography. Two peptides with high XOD inhibitory activity purified from ATH were identified as Pro-Asp-Leu (PDL, 344.87 Da) and Ser-Val-Gly-Gly-Ala-Leu (SVGGAL, 504.26 Da) by UPLC-MS/MS, which possessed high in vitro XOD inhibitory activity with the IC50 values of 4.37 +/- 0.11 mg mL(-1) and 5.59 +/- 0.09 mg mL(-1), respectively. Molecular simulation indicated that PDL and SVGGAL binded to XOD mainly through hydrogen bond and hydrophobic interaction, thereby inhibiting XOD activity. The research results suggested that the two peptides had potential application prospects as a safe XOD inhibitor substance for hyperuricemia treatment.