Identification of a Novel Bioactive Peptide Derived from Frozen Chicken Breast Hydrolysate and the Utilization of Hydrolysates as Biopreservatives

SIMPLE SUMMARY: The development of food-derived bioactive peptides with beneficial health effects has gained a lot of attention and is regarded as a natural approach to enhancing human health. Bioactive peptides are short protein fragments with beneficial biological functions. Frozen chicken is a protein-rich food that contains bioactive peptides, which can be produced through enzymatic hydrolysis. The current study was designed to purify and characterize bioactive peptides from frozen chicken breast. The obtained findings showed that frozen chicken breast is a promising source of bioactive peptides with inhibitory action on the angiotensin-converting enzyme and antimicrobial and antioxidant properties. Furthermore, chicken hydrolysates could significantly reduce bacterial growth and lipid oxidation when applied to chicken breast. Muscle-derived hydrolysates, particularly chicken hydrolysate, hold promise as potential natural preservatives to replace chemical additives. ABSTRACT: Frozen chicken breast was hydrolyzed by treatment with thermolysin enzyme to obtain a chicken hydrolysate containing bioactive peptides. After that, a peptide was purified from the chicken hydrolysate utilizing a Sep-Pak C18 cartridge and reversed-phase high-performance liquid chromatography (RP-HPLC). The molecular weight of the chicken peptide was 2766.8. Protein sequence analysis showed that the peptide was composed of 25 amino acid residues. The peptide, designated as C25, demonstrated an inhibitory action on the angiotensin-converting enzyme (ACE) with a half maximal inhibitory concentration (IC(50)) value of 1.11 µg/mL. Interestingly, C25 showed antimicrobial activity against multi-drug resistant bacteria Proteus vulgaris F24B and Escherichia coli JM109, both with MIC values of 24 µg/mL. The chicken hydrolysate showed antioxidant activity with an IC(50) value of 348.67 µg/mL. Furthermore, the proliferation of aerobic bacteria and Enterobacteriaceae as well as lipid oxidation were significantly reduced when the chicken hydrolysate was used as a natural preservative during cold storage of chicken breasts. Hydrolysates derived from muscle sources have the potential to be used in formulated food products and to contribute positively to human health.