Antimicrobial Resistance Patterns of Probiotic Strains Isolated from Probiotic Yogurts of Iran

Probiotics mainly belong to Lactobacillus spp. and they are useful for humans in appropriate amounts. The present study aimed to determine antibiotic resistance patterns of such bacteria isolated from probiotic yogurts of Iran. Probiotic bacteria were isolated from 7 yogurt samples and the isolates were identified by conventional methods and then confirmed using polymerase chain reaction (PCR) technique. Antibiotic susceptibility test was performed by disc diffusion test in order to determine isolates antibiotic resistance patterns. From 7 yogurt samples, 8 isolates were recovered and PCR assay also showed that the isolates belong to Lactobacillus delbrueckii subsp. bulgaricus. Antibiotic susceptibility testing showed that three isolates from three brands were resistant to vancomycin and gentamicin. Other strains were susceptible to all tested antibiotics. Low resistance rate to antibiotics among Iranian probiotic bacteria indicate that the consumption of their products is safe but their clearance following antibiotic therapy can be unfavorable. Hence, applying probiotic strains with non-transferrable resistance elements in probiotic yogurts can be a useful strategy to make stable probiotic products.