Colonization potential of plantaricin-producing Lactobacillus plantarum SF9C and S-layer carrying Lactobacillus brevis SF9B among gut microbiota

Background: The influence of an S-layer carrying Lactobacillus brevis SF9B and plantaricin-producing Lactobacillus plantarum SF9C on the gut microbiota composition was evaluated in the rats. Considering the probiotic potential of Lb. brevis SF9B, this study aimed to examine the antimicrobial activity of Lb. plantarum SF9C and potential for their in vivo colonization, which could be the basis for the investigation of their synergistic functionality. Results: We identified plantaricin encoding cluster in Lb. plantarum SF9C, a strain which efficiently inhibited Listeria monocytogenes ATCC®19111™ and Staphylococcus aureus 3048. Contrary to a plantaricin-producing SF9C strain S-layer carrying SF9B strain excluded Escherichia coli 3014 and Salmonella enterica serovar Typhimurium FP1 from Caco-2 cells. DGGE analysis of the V2-V3 region of the 16S rRNA gene confirmed the transit of the two selected lactobacilli through the gastrointestinal tract. Microbiome profiling via the Illumina MiSeq platform revealed the prevalence of Lactobacillus spp. in the gut microbiota of rats suggesting their colonization potential in GIT.Conclusion: The combined application of the two strains could influence intestinal microbiota composition, which is reflected through the increased abundance of Lactobacillus genus, but also along with the abundances of other bacterial genera, either in the model of health or aberrant microbiota. Obtained results contribute to the functional aspect of SF9C and SF9B strains which could be incorporated in the probiotic-containing functional foods to beneficially influence gut microbiota composition.