Assessment of Probiotic Properties of Some Bacteria Isolated from Dairy Products

Objectives: A study was undertaken to isolate bacteria from fermented dairy products and evaluate their probiotic potential. Methods: From the colonies formed on MRS agar plates, 8 bacterial isolates were selected and evaluated for their anti-microbial and cholesterol assimilation capability. Results: Among the tested isolates, P3 showed maximum antimicrobial activity against Staphylococcus aureus ATCC 6538 and P8 showed maximum antimicrobial activity against Salmonella enteritidis ATCC 13076, Listeria monocytogenes ATCC 7644 and Escherichia coli ATCC 35150. The isolate P8 also showed highest cholesterol assimilation capability (41.91%) which is followed by isolate P3 (35.95%). Based on the morphological, biochemical and physiological characteristics the isolate P3 and P8 were identified as Lactococcus lactis and Streptococcus thermophilus, respectively. Conclusion: The studied fermented dairy products available in Bangladesh contain adequate number of lactic acid bacteria and some of the bacterial isolates possess appreciable probiotic properties.