Evaluation of the probiotic properties of Bacillus spp. strains isolated from Tunisian hypersaline environments

Bacillus species are ubiquitous and diverse both in the terrestrial and marine ecosystems. In this study, Bacillus species were isolated from Tunisian hypersaline environments and their probiotic properties were studied. In total, 13 strains were identified as a Bacillus spp. Antagonism assay revealed an inhibitory effect of these strains against pathogenic bacteria. Cell surface hydrophobicity values ranged between 0.33 and 30%. The tested strains were able to produce extracellular enzymes such as amylase, lipase, caseinase, and lecithinase. Qualitative analysis of biofilm results show that seven strains were able to produce slime on Congo red agar. Furthermore, the investigated strains were fairly adhesive to glass and polystyrene with values ranging from 0.07 to 0.70 at 570 nm. Key words: Bacillus spp., hypersaline, antagonism, extracellular enzymes, adhesion.