Probiotic properties of Ligilactobacillus salivarius K611 isolated from chicken feces and its antibacterial activity against Salmonella Typhimurium

Lactic acid bacteria with high anti- Salmonella activity were isolated from chicken feces. A total of 127 LAB strains were collected; among them, 7 inhibited both Salmonella Typhimurium CIP58.58 and Escherichia coli TISTR 527. Subsequently, 3 strains showing γ-hemolytic activity were selected for further assessment of their probiotic properties. Ligilactobacillus salivarius K611 was identified as a potential probiotic strain based on its survival under artificial gastric conditions, hydrophobicity, and sensitivity to multiple antibiotics. Draft genome sequencing of L. salivarius K611 revealed several genes involved in carbohydrate metabolism, stress responses, and adhesion, which are recognized for their beneficial effects in probiotic bacteria. We also detected a bacteriocin gene likely responsible for bacteriocin production. Additionally, based on genetic analyses of antibiotic resistance and virulence factors, L. salivarius K611 is postulated to be safe. Electron microscopy strongly supported the bacteriostatic effect of L. salivarius supernatant, revealing severe leakage and cell disruption of S. Typhimurium CIP58.58. In conclusion, the analysis through genomic and phenotypic assay confirms the potential of L. salivarius K611 as a promising probiotic candidate. • L. salivarius K611 demonstrates strong antibacterial activity against Salmonella. • L. salivarius K611 possesses great probiotic and safety properties. • Draft-genome of L. salivarius K611 was first sequenced. • Genes for bacteriocin production were analyzed in the genome of L. salivarius K611. • L. salivarius K611 can be used as a probiotic.