Insight into dynamic interaction of bonito sauce-derived functional peptide Ala-Gly-Pro with serum albumin

From the perspective of functional food development, an in-depth study of the interaction between food-derived angiotensin-converting enzyme inhibitory peptides (ACEIPs) and serum albumin is crucial for understanding their physicochemical stability after absorption within the body. Thus, this study explored the interaction mechanisms of bovine serum albumin (BSA) with bonito sauce-derived ACEIP Ala-Gly-Pro (AGP) using biosafety, biophysics, and computational biology. The results indicated that AGP demonstrated good biosafety, and competitively inhibited ACE activity (500 ± 24 μmol/L). Multi-spectroscopic and isothermal titration calorimetry analysis proved that AGP could spontaneously insert in the site I of BSA and form a non-covalent complex, clearly changing the structure and microenvironment of BSA. Molecular docking and molecular dynamics simulations successfully revealed the dynamic conformational changes and non-covalent interactions in the BSA–AGP complex. These findings provide valuable data on food-derived ACEIP AGP, serving as a reference and model for studying similar peptides in developing antihypertensive functional foods.