Online proteolysis and specific affinity enrichment of ACE inhibitory peptides on a magnetic nanoplatform from Torreya grandis protein.

Although chemically synthesized ACE inhibitors are effective, they frequently cause side effects like cough, hypotension, and angioedema, which limits their use in clinical settings. However, these drawbacks have spurred interest in exploring natural sources for novel ACE inhibitory compounds. In this study, we developed a magnetic Fe3O4 nanoplatform capable of specifically recognizing ACE inhibitory peptides. This strategy was employed for the specific enrichment peptides with ACE-inhibitory activity derived from Torreya grandis protein digests. Using immobilized enzyme technology combined with computational docking evaluation, 61 peptides exhibiting ACE inhibition were successfully identified, five of which exhibited binding energies below -9 kcal/mol. Among them, CGDDGY showed the highest inhibition rate (37.43% at 800 μmol/L). This method overcomes the limitations of conventional separation approaches based on polarity or molecular weight, providing a promising pathway for developing food-derived antihypertensive agents and a technical paradigm for the precise screening of natural functional factors.