Antimicrobial peptides from the edible insect Musca domestica and their preservation effect on chilled pork

摘要

Antimicrobial compounds from natural sources are a promising alternative to address the consumer demand of food without chemical additives. In this study, antimicrobial peptides (AMPs) from infected Musca domestica pupae (Md-AMPs) bred under clean conditions were isolated and prepared on a large scale. In these Md-AMPs, seven AMPs families were identified by liquid chromatography–tandem mass spectrometry. Md-AMPs at concentrations from 0.4 to 0.8 mg/ml exhibited antibacterial activity and showed negligible hemolytic activity against human erythrocytes. Md- AMPs increased bacterial membrane permeability of four tested strains, resulting in the leakage of phosphorus-containing materials and Ca~(2+). Md-AMPs bound plasmid DNA and inhibited its migration in a concentration-dependent manner. Treatment with Md-AMPs alone or in combination with nisin, and ethylenediaminetetraacetic acid was efficient in inhibiting bacterial growth in chilled pork and extended the shelf life up to 6 days.