Effect of Marine Bacillus Metabolites on Biofilm Formation by Listeria monocytogenes

Listeria monocytogenes, a causative agent of sapronoses, can enter the human body through ingestion of contaminated marine hydrobionts, posing a significant public health risk. Mono- and polycultural biofilms of microorganisms were detected spectrophotometrically. The study demonstrated that metabolites from marine-origin Bacillus bacteria stimulate the formation of L. monocytogenes monocultural biofilms, as well as mixed biofilms of L. monocytogenes and the marine bacterium Micrococcus luteus. In mixed biofilms of L. monocytogenes and a marine Flavobacterium bacterium genus, Bacillus megaterium metabolites exhibited both stimulating and inhibitory effects, depending on concentration. These findings suggest that Bacillus-derived metabolites can enhance the growth and proliferation of L. monocytogenes in biofilms, potentially influencing the epidemic risks in recreational areas of Peter the Great Gulf.