Antimicrobial property of recombinant Lactolisterin BU in vitro and its initial application in pork refrigerated storage

Abstract

AbstractLactolisterin BU is a novel bacteriocin identified from Lactococcus lactis in 2017. It exhibits antimicrobial activity against food spoilage and foodborne pathogens. In this study, Lactolisterin BU was expressed in Pichia pastoris (P.pastoris) and isolated from the supernatant of yeast culture for the first time. It was found to exhibit a broad antimicrobial spectrum and rapid bactericidal activity against foodborne bacterial pathogens, both gram-positive and gram-negative ones, with minimum inhibition concentrations ranging within 10–60 μg/mL. The recombinant Lactolisterin BU (rLactolisterin BU) also had an antioxidant effect and was resistant to heating, acid–base, and high-dose-saline treatments and barely had any hemolytic activity or cytotoxicity. Moreover, rLactolisterin BU effectively suppressed the growth of bacterial pathogens; suppressed the increases in pH, total volatile basic nitrogen (TVB-N), and thiobarbituric acid reactive substances (TBARS) of pork samples; and maintained a high quality of fresh pork during storage at 4 ℃. Furthermore, rLactolisterin BU effectively inhibited the growth of three kinds of bacteria in a pork-spoilage model. Taken together, rLactolisterin BU could be a promising preservative for food storage.