Comparative accounts of probiotic characteristics of Bacillus spp. isolated from food wastes

Bacillus strains JHT3, DET6 and DET9 were selectively isolated from food wastes. These isolates exhibited various degrees of essential probiotic qualities and varied level of susceptibility patterns against tested antibiotics. Spores of DET9 elucidated best tolerance against simulated gastro-acidic conditions whereas DET6 showed best steadiness against simulated intestinal conditions. DET6 exhibited better antimicrobial activity than JHT3 and DET9 against unsafe organisms viz Staphylococcus aureus, Micrococcus flavus, Proteus vulgaris, Salmonella typhi and Escherichia coli. Susceptibility of these isolates to antibiotics decreases the illustration to offer resistance determinants to other organisms if administered in the form of probiotic preparations. JHT3, DET6 and DET9 showed high homology with Bacillus megaterium, (98%) Bacillus subtilis (99%) and Bacillus thuringiensis, respectively, using partial 16S r-RNA gene sequencing. Biochemical characterizations have supported the results of partial 16S r-RNA gene sequencing for JHT3 and DET6 but did not for DET9 and revealed its innovation. These isolates exhibited zero mortality of fishes in a 60 days trial, when fishes (Surfi tetra) were challenged up to 100 ppm cell concentration, with their daily diet.