Exploration, sequence optimization and mechanism analysis of novel xanthine oxidase inhibitory peptide from Ostrea rivularis Gould.

Xanthine oxidase (XO) inhibitory peptides are secure and efficient functional food ingredients for treating or alleviating hyperuricemia (HUA). In this study, ultrafiltration and molecular exclusion chromatography were used to separate and purify enzymatic lysate of oyster protein, three novel peptides (ALSGSW, GGYGIF and MAIGLW) with strong XO inhibitory activity were screened by LC-MS/MS identification and molecular docking technology. Then, the mechanism of action between peptides and the XO was revealed by molecular docking technology, and the structure of the peptide was rationally designed on this basis. The results showed that replacing N-terminal Gly of peptide GGYGIF with Trp can significantly improve its XO inhibition rate, and peptides formed by the simple structure amino acid was connected to the aromatic amino acids has preferable inhibitory activity. These results showed that oyster was a good source of XO peptide inhibitors, molecular docking technology was an effective tool for obtaining highly active peptides.