Project description:The increased prevalence of Salmonella spp. resistance in swine spurs the search for alternatives to antibiotics. Microcin J25 (MccJ25), a bacteriocin produced by Escherichia coli, is a potent inhibitor of several pathogenic bacteria including Salmonella enterica. In this study, we aimed to evaluate in vitro the impact of MccJ25 on the metabolic activity of the swine colonic microbiota. The PolyFermS in vitro continuous fermentation model was used with modified Macfarlane medium to simulate the porcine proximal colon. During 35 days of fermentation, a first-stage reactor containing immobilized swine fecal microbiota fed two second-stage control and test reactors operated in parallel and used to test the effectsof MccJ25 on the composition and the metabolic activity of the microbiota. Reuterin, a broad spectrum antimicrobial produced by Limosilactobacillus reuteri and the antibiotic rifampicin were tested for comparison. LC-MS analysis of the cell extracts was used to assess the bacteriocin/antibiotic degradation products and monitor changes in the swine colonic microbiota metabolome.
