▎ 摘　　要

The ACE inhibitory peptides have been characterized from the enzymatic digestion product of bighead carp protein and bioconjugated with graphene oxide (GO) to enhance its activity. The results showed that aspartic acid and glutamic acid had the highest levels in ultrafiltration fractions (<5 kDa), where eight potential ACE inhibitory peptides were also identified (ADSNHKAF, KLWHHTF, LLRLHF, PPSEPTKL, VEKFPLF, YLRLHF, YYKLKPLL, YYKLKPML). Among the eight peptides, YLRLHF showed the best ACE inhibitory activity (IC50 = 121.90 mu M) and was a competitive inhibitor. Molecular docking experiments showed that YLRLHF formed four hydrogen bond interactions in the ACE protein pocket, coordination bonding with Zn2+, and 7C-7C conjugation interactions to His421. GO elevated the ACE inhibitory activity of YLRLHF (at 0.1 mg/mL) from 43.36% to 51.72%. The structural characterization results obtained from FI-IR, XPS, SEM, and TEM demonstrated the successful combination of GO and YLRLHF. Additionally, biocouples of ACE inhibitory peptides from bighead carp proteins with GO might be potential candidates for future functional foods and antihypertensive drugs.