Preparation of xanthine oxidase inhibitory peptides from peanut meal protein and their intervention effects on...

The bioactivity of peanut meal protein-derived hydrolysates is enhanced via enzymatic hydrolysis, whereas single-enzyme processing restricts their bioactive potential. To this end, a dual-enzyme system combining Alcalase with the aminopeptidase (bvLAP) isolated by our team was employed to hydrolyze peanut meal protein, aiming to elucidate the regulatory mechanisms of the resulting hydrolysate (HST) on hyperuricemia (HUA).

Optimal hydrolysis conditions were: pH 9.0, enzyme dosage of 8000 U g^-1 Alcalase and 5% (w/w) aminopeptidase, temperature of 55 °C, duration of 150 min, and substrate concentration of 45 g L^-1. Under these conditions, HST achieved 24.8 ± 0.18% degree of hydrolysis and 85.95 ± 0.39% xanthine oxidase (XO) inhibition rate. HST outperformed Alcalase hydrolysate in both hydrolysis degree and in vitro antioxidant activities, while demonstrating superior stability across varying temperatures, pH levels, and simulated gastrointestinal digestion in vitro. In HUA mice, high-dose peanut meal peptide (A3-H) significantly lowered serum concentrations of uric acid, creatinine, and blood urea nitrogen, decreased hepatic activities of XO and adenosine deaminase, and suppressed renal levels of inflammatory cytokines (IL-1β, IL-6, IL-18, TNF-α). Histopathological analysis confirmed that A3-H mitigated hepatic and renal tissue damage in HUA mice. Western blotting revealed that A3-H downregulated the expression of GLUT9, URAT1, and OAT4 transporters, while upregulating ABCG2, OAT1, and OAT3 transporters in the kidney.

The peanut meal peptide A3 obtained through double-enzyme hydrolysis can alleviate HUA by modulating renal uric acid transport pathways. The study has laid a solid foundation for the development of a functional peanut dietary supplement targeting HUA. © 2026 Society of Chemical Industry.