Protective effects of milk fermented by Lactobacillus plantarum B7 from Brazilian artisanal cheese on a Salmonella enterica serovar Typhimurium infection in BALB/c mice

•New probiotic Lactobacillus plantarum strain from Brazilian’s Minas artisanal cheese.•Protective effect of L. plantarum B7 sample was observed in murine salmonellosis model.•B7 reduces local ileum inflammatory cytokines expression in its protective effect.•Salmonella abundance is reduced with B7 treatment and population diversity in ileum is maintained. Milks fermented with Lactobacillus strains showing probiotic properties are an important tool to maintain gastrointestinal health. In this study, Lactobacillus plantarum (B7), from Brazilian artisanal cheese, was evaluated for its action against Salmonella enterica serov. Typhimurium, first by co-incubation and supernatant in vitro methods. In vivo, male BALBC/c mice received daily, for seven days, an oral dose of milk fermented by the B7 sample, and then were challenged orally with S. Typhimurium. Control group received sterile milk. Antagonism was observed in vitro. In vivo, administration of fermented milk showed a protective effect demonstrated by lower bacterial translocation, histological lesions, weight loss and cumulative mortality, when compared with control group. Additionally, reduction in IFN-γ and IL-6 (with increase in TGF-β) relative expressions were observed in ileum of treated mice. Finally, ileal Salmonella population was reduced in mice receiving B7 sample. Concluding, our results indicate that L. plantarum B7 presents probiotic properties.