Bacillus licheniformis isolated from Korean traditional food sources enhances the resistance of Caenorhabditis elegans to infection by Staphylococcus aureus.

We investigated whether Bacillus spp., newly isolated from Korean traditional food resources, influence the resistance of hosts to foodborne pathogens, by using Caenorhabditis elegans as a surrogate host model. Initially, we selected 20 Bacillus spp. that possess antimicrobial activity against various foodborne pathogens, including Staphylococcus aureus. Among the selected strains, six strains of Bacillus spp. used in preconditioning significantly prolonged the survival of nematodes exposed to S. aureus. Based on 16S rRNA gene sequencing, all six strains were identified as B. licheniformis. Our findings suggest that preconditioning with B. licheniformis may modulate the host defense response against S. aureus.