摘要:The viable microbial food supplements which beneficially influence the health of humans are known as probiotics. Antibacterial activity is one of the important probiotic properties for a strain to be a functional probiotic.The three Lactobacillus strains namely Lactobacillus plantarum CM1, Lactobacillus fermentum CM4 and Lactobacillus casei subsp. casei CM6 were isolated from cow milk samples collected from Udaipur city. Their antagonistic activity was tested against five pathogenic bacteria such as Serratia marcescens NCDC 108, Enterobactor aerogens NCDC 106, Proteus vulgaris NCDC 73, Pseudomonas aeruginosa NCIM 5029, and Micrococcus luteus NCDC 131 using agar well assay method. The results showed that the Lactobacillus strains namely Lactobacillus plantarum CM1, Lactobacillus fermentum CM4 and Lactobacillus casei subsp. casei CM6 were able to inhibit the growth of all the pathogenic bacteria in varying degrees. All the three Lactobacillus isolates were found to be the most sensitive against Micrococcusluteus than the rest of the pathogenic bacteria used in the study. The inhibition observed in the case of all the isolates that have antagonistic effect may be due to the production of organic acids as well as other compounds such as bacteriocins, hydrogen peroxide etc.