Prevalence of Multi-Drug Resistance Traits in Probiotic Bacterial Species from Fermented Milk Products in Bangladesh

Aims: Matured nourishment like yogurt and cheese are great wellsprings of probiotic living beings. The present study was carried out for isolation, identification and antibiotic profiling of some important bacteria in, local fermented milk-products sold in the market of Dhaka, Bangladesh.

Methodology: Twenty types of yogurt and fifteen types of cheese samples were collected from two different local market. De Man, Rogosa and Sharpe agar (MRS agar) and Streptococcus thermophilus agar (ST agar) were used for the isolation of probiotic micro-organisms from these different fermented dairy products. Characterization of lactic acid bacteria belonging to the species of Lactobacillus acidophilus, Lactobacillus bulgaricus and Streptococcus thermophilus was done by using morphological feature, Gram staining, biochemical tests (catalase test, some carbohydrate fermentation tests, alpha haemolysis test, starch hydrolysis test, bile salt tolerance test). The antibiotic profiling was performed by utilizing twelve distinct antibiotics: amikacin (10 μg), amoxicillin (15 μg), azithromycin (30 μg), bacitracin (30 μg), chloramphenicol (30 μg), ciprofloxacin (10 μg), erythromycin (30 μg), gentamicin (30 μg), kanamycin (30 μg), penicillin g (30 μg), tetracycline (15 μg), vancomycin (15 μg) to identified the multi-drug resistance of probiotic micro-organisms.

Results: The outcomes demonstrated that specific bacterial species (L. acidophilus, L. bulgaricus and S. thermophilus) were utilized in the production of yogurt and cheese samples, that may have unnecessary antibiotic resistances which can be a risk if they transfer antibiotic resistance genes to pathogenic microbes. Notably, L. bulgaricus was effectively susceptible against bacitracin and penicillin g.

Conclusion: Yogurt and cheese are one kind of probiotic source, made up by using probiotic starter cultures (Lactobacillus spp. and Streptococcus thermophilus) which were identified in this study. Most of the probiotic micro-organisms were resistant against these widely accepted commercial antibiotics. These resistant lactic acid bacteria may transfer their resistance genes to pathogenic microorganisms. It can be a significant cause of concern for human and animal health.