Resistance of pathogenic bacteria is currently one of the major medical problems. Most microbial infections are based on the formation of biofilms, which are a significant reservoir of pathogens. The aim of this study is to determine the antibiofilm and antimicrobial activity of biosurfactants isolated from intestinal lactobacilli and marine bacteria. Biosurfactants (BS) isolated from the strains L. fermentum 2I3, L. fermentum B2/6, L. reuteri SL16, L. reuteri B6/1, S. luteola 3/22, Brevibacillus sp. 4/9, Brevibacillus sp. 2/30 and B. amyloliquefaciens 1/6K significantly (p < 0.001) inhibited the biofilm formation of S. aureus CCM 3953 and P. mirabilis CCM 7188, with higher inhibition detected in BS of marine bacteria when compared to BS isolated from lactobacilli. The results suggest that the mechanism of the antibiofilm effect of BS isolated from lactobacilli against both the reference strains is the same and it is not the result of their antimicrobial action. In contrast, the mechanism of the antibiotic effect of BS isolated from marine bacteria probably depends on the properties of the indicator strain. Key words: biosurfactants biofilm pathogens inhibition.

The effect of Limosilactobacillus fermentum 2i3 and 0.6% addition of humic substances on production parameters and the immune system of broilers