In vitro antagonistic effects of Lactobacillus acidophilus PTCC 1643 (DSM 20079) and Lactobacillus plantarum PTCC 1058 (ATCC 8014) against isolated bacteria from Urinary Tract Infections

Document Type: Research Article


Department of Microbiology, College of Basic Sciences, LahijanBranch, Islamic Azad University, Lahijan, Iran.


Lactic acid bacteria (LAB) are gram positive and non- spore forming bacteria that can produce some special substances for growth inhibition of pathogenic, non-pathogenic and food spoilage bacteria. The aim of this study was to determine the inhibitory effects of Lactobacillus acidophilus PTCC1643 (DSM 20079) and Lactobacillus plantarum PTCC 1058 (ATCC 8014) cultural supernatants against urinary tract infections (UTI) agents, including Klebsiella pneumoniae, Enterobacter aerogenes, Escherichia coli and Lactobacilli sppin MRS Broth. Selective culture media and biochemical tests were used for UTI bacteria isolation. Inhibitory effects were evaluated using well diffusion agar and the inhibitory zone diameters were measured after overnight incubation at 35-37°C. The highest inhibitory effect were obtained using L. plantarum PTCC 1058 cultural supernatant against E.coli and the lowest one using L.acidophilus PTCC 1643 cultural supernatant against K.pneumoniae. These Lactobacilli spp.were showed inhibitory effects on all of the isolated bacteria. Totally, L.plantarum PTCC 1058 showed inhibitory activity more than L.acidophilus PTCC 1058. The findings of this study showed that Lactobacilli spp. as a capable candidate for producing antibacterial compounds and using them for treatment and industrial usage.