Eleven potential bacterial probiotic isolates of Enterococcus, Bacillus and Lactobacillus spp. were examined
for their antagonistic activity against standard antibiotic resistant pathogenic bacteria. Antagonistic activity was exhibited by most of these indigenous isolates against selected pathogens, but it was very strong against Listeria monocytogenes-MTCC 839 and Staphylococcus aureus-MTCC 96. These antagonistic substances were proteinaceous in nature, heat stable and retained their activity in presence of catalase, protease inhibitor and detergents. Based on these traits, the antagonistic substances were designated as bacteriocin like substances. Hydrogen peroxide production
was exhibited by only three isolates (two Enterococcus faecium and one Lactobacillus fermentum).