ANTIBIOTIC SUSCEPTIBILITY OF POTENTIALLY PROBIOTIC LACTOBACILLUS STRAINS

Abstract

Susceptibility of 29 Lactobacilli to 13 antibiotics was assayed by paper disc diffusion method. Plasmids and gastrointestinal tolerance were detected. The relationship between plasmids andantibiotic resistance was discussed. The results showed that all of the strains were resistant to bacitracin, polymyxin B, kanamycin, and nalidixic acid. Many strains were relatively sensitive tochloramphenicol and tetracycline. Six strains contained plasmids and showed good gastrointestinal tolerance. β-lactam resistance gene blr was found in the plasmid of L. plantarum CICC 23180by PCR. The study will be helpful to promote the safety evaluation and development of potentially probiotic lactic acid bacteria.