Susceptibility of Lactobacillus pentosus strains isolated from fermented products to streptomycin and kanamycin

Streptomycin and kanamycin susceptibility of Lactobacillus pentosus P and Ind-3 were tested with paper discs in MH agar by disc diffusion techniques. The antibiotic susceptibility was evaluated according to the NCCLS standard. Genes responsible for resistances to streptomycin [aadA and aadE], and kanamycin [aph(3”)-III] were detected by PCR. The sequences of the target band were detected and compared using the BLAST program. The results showed that Lactobacillus pentosus P and Ind-3 were resistant to kanamycin. To streptomycin, the strain Ind-3 was resistant, but P was sensitive. And the kanamycin-resistant gene was in plasmid. The resistant plasmid was highly similar to Enterococcus faecalis plasmid pSL1. Currently, new beneficial bacteria are being developed continuously into market. If they showed antibiotic resistance and the resistance can be transferred to other bacteria, especially pathogenic microorganisms, it will be a serious social problem. So, the antibiotic resistance should be checked firstly before subsequent utilization. The results confirm that antibiotic susceptibility was a very important feature in the selection of potentially probiotic lactic acid bacteria.