Preliminary Study on the Functions of Peptides Obtained from White Mullet (Ophiocephalus argus var. Kimnra) Meat

To explore the functions of peptides obtained from white mullet (<i>Ophiocephalus argus</i> var. Kimnra) meat, the meat was hydrolyzed via simulated digestion in vitro, and the functions (milk secretion ability, antioxidant activity, angiotensin-converting enzyme (ACE) inhibitory activity, and Fe²⁺ chelation) of the obtained peptide were evaluated. The results indicated that both low-dose and high-dose peptide promoted milk secretion in lactating rats in vivo; the peptides had scavenging effects on free radicals of 1,1-diphenyl-2-trinitrophenylhydrazine (DPPH), 2,2'-azino-bis (3-ethylbenzo-thiazoline-6-sulfonic acid) diammonium salt (ABTS), OH^-, and O^2-, and the EC₅₀ concentrations were 55.94 mg/mL, 10.14 mg/mL, 52.92 mg/mL, and 28.53 mg/mL, respectively. The peptides had an inhibitory effect on ACE, and the IC₅₀ concentration was 15.81 mg/mL. The peptides had a chelating ability to Fe²⁺, and the IC₅₀ concentration was 69.05 mg/mL. These results indicate that peptides obtained from white mullet meat exhibit milk secretion-promoting ability, antioxidant activity, ACE-inhibitory activity, and Fe²⁺ chelation, making this an effective approach for isolating specific functional peptides and identifying their sequences from the digested solution of white mullet meat.