Keywords : Lactobacillus spp
Study Antibacterial Activity of Lactobacillus brevis Against Escherchia coli and Enterobacter aerogenus Causes Diarrhea Among Children in Holy City of Karbala.
journal of kerbala university,
Volume 10, Issue 4, Pages 193-202
The study included isolation and identification of pathogenic bacterial which responsible for diarrheal infection to 39 stool samples were collected from children under five years of age suffering from diarrhea attending to education children hospital for of education in the Holy Karbala during the period from May to August 2013, as it was obtained on 39 bacterial isolates from these samples, which have been diagnosed by using differential mediums, biochemical tests and by using Api 20 kits, and appeared that isolates belonging to Escherichia coli (43.58%) and Enterobacter aerogenes (30.76%) are the most common isolates that have been selected to complete the rest of the steps of the study.
A total of ten Lactobacillus spp. isolates have been obtained from different sources such as (Yoghurt ,Whey and Raw milk( ,and only one of them belong to Lactobacillus brevis showed ability to produce the cell free supernatant (biosurfactant) and showed antimicrobial activity against all pathogenic bacterial strains tested .The MIC and Sub-MIC of the cell free supernatant (biosurfactant) extracted from Lactobacillus brevis isolate was determined against studied pathogenic bacteria and the results showed that the MIC of the biosurfactant was 70 mg/ml and Sub-MIC was 60 mg/ml respectively, these results indicates that biosurfactant must be used in high concentration to inhibit the growth of pathogenic bacteria.