High F-Value Oligopeptides from Zanthoxylum bungeanum Seeds: Preparation Optimization and in Silico Screening of Xanthine Oxidase Inhibitory

In this study, the optimal preparation conditions for high F-value oligopeptides from Zanthoxylum bungeanum seeds and xanthine oxidase (XOD) inhibitory were investigated. Based on the efficient enzymatic hydrolysis of Zanthoxylum bungeanum seeds protein, the activated carbon adsorption aromatic amino process was investigated by considering the apparent F-value and peptide retention rate of the enzymatic hydrolysates. Subsequently, high F-value oligopeptides were obtained via ultrafiltration. The molecular mass ranges of the resulting fraction were determined based on XOD inhibitory activity, and the potential bioactive potential bioactive peptide sequences for uric acid-lowering were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS), bioinformatics and molecular docking. The results showed that the optimal activated carbon adsorption conditions were as follows: 200-mesh activated carbon, a carbon-to-liquid ratio of 1:15 (g/mL), pH4.0, adsorption temperature 45 ℃, and adsorption time 4 h. Under the conditions, the apparent F-value and peptide retention rate of the resulted fraction were 13.47 and 5.57%, respectively. After further ultrafiltration, a high F-value oligopeptide fraction with an F-value of 24.51 was obtained, in which peptides with a molecular weight between 200~1000 Da accounted for 92.06% of the total. The XOD inhibitory activity was 66.06% at a concentration of 1 mg/mL. Furthermore, four peptides were found to have the highest potential for anti-XOD activity, namely LLRG, LPRG, LPVG, and LPGTL. Hydrogen bond, electrostatic interactions and hydrophobic interactions played a vital role in the uric acid-lowing effects of these peptides. In conclusion, the high F-value oligopeptides from Zanthoxylum bungeanum seeds have the potential xanthine oxidase inhibitory.