In Silico and In Vitro Screening and Mechanisms of Angiotensin I-Converting Enzyme Inhibitory Peptides from Protein Hydrolysates of Royal Jelly

This study aimed to identify angiotensin I-converting enzyme (ACE) inhibitory peptides from royal jelly (RJ) proteins and elucidate their inhibition patterns and mechanisms. RJ proteins were analyzed for ACE inhibition potential using in silico tools, and suitable enzymes were selected for peptide release. Hydrolysis conditions were optimized using response surface methodology (RSM), and the resulting peptides were fractionated and purified. Mass spectrometry identified 57 peptides, with seven selected for synthesis based on scoring. IDFDF, DVNFR, and SFHRL showed the highest ACE inhibition, with IC50 values of 16.9 μM, 42.5 μM, and 242.6 μM, respectively. Lineweaver-Burk plots revealed IDFDF as a competitive inhibitor, DVNFR as a non-competitive inhibitor, and SFHRL as a mixed inhibitor. Molecular docking indicated that peptide-ACE interactions were primarily mediated through hydrogen bonds and Zn(II) coordination. These findings support the high-value utilization of RJ and the development of food-derived ACE inhibitory peptides.