Antibacterial Activity and Potential Application in Food Packaging of Peptides Derived from Turbot Viscera Hydrolysate

As a good choice for food preservation, antimicrobial peptides (AMPs) have received much attention in recent years. In this paper, peptides derived from the turbot viscera hydrolysate were identified by ultraperformance liquid chromatography–quadrupole time-of-flight mass spectrometry (UPLC–Q-TOF-MS/MS), and the physicochemical properties and structural characteristics were analyzed by in silico tools. Furthermore, three cationic peptides with potential hydrophobicity and amphipathy were synthesized; their cytotoxicity, hemolysis, and antibacterial activities were investigated. In particular, Sm-A1 (GITDLRGMLKRLKKMK), a peptide with 16 amino acids, showed an outstanding antibacterial activity against both Gram-positive and Gram-negative bacteria by damaging the cell membrane integrity. Moreover, Sm-A1 was successfully loaded into hydroxyl-rich poly(vinyl alcohol) (PVA)/chitosan (CS) hydrogel to improve the antibacterial activity and biofilm inhibition effect. PVA/CS+7.5‰ Sm-A1 hydrogel can satisfactorily protect the salmon muscle from the microbiological contamination and texture deterioration.