Abstract
This research work was executed to isolate potential Lactobacillus spp. from local raw goat milk samples for their antimicrobial activities against different human intestinal pathogens. Isolation of such bacteria was carried out by Man Rogosa Sharpe (MRS) agar media. Identification of the isolated strain was conducted according to the morphological and biochemical tests. Furthermore, growth optimization and their antimicrobial activity also studied against the pathogenic bacteria (Escherichia coli ATCC 25921, Pseudomonas aeruginosa ATCC 9027, Vibrio cholera ATCC 14035 and Salmonella enteric ATCC 14028). A total of 23 isolates were obtained from the raw goat milk samples, among them four isolates were selected on the basis of their antimicrobial activities against pathogenic bacteria. The Lactobacillus spp. showed better growth in 6.5 to 7.5 pH range and temperature range was 35 to 40°C. Thus it can be said that the goat milk provides a natural dwelling place for Lactobacillus spp., which are beneficial to human health. Key words: Antimicrobial activity, growth optimization, intestinal pathogens, Lactobacillus spp., Man Rogosa Sharpe (MRS) agar media, pH, raw goat milk.
Highlights
Lactobacillus is one of the most important genera of lactic acid bacteria (LAB) (Coeuret et al, 2003)
Cross-streak method was used to detect the anti-microbial activity of Lactobacillus spp. (Lertcanawanichakul and Sawangnop, 2008). against selected gram negative pathogenic bacteria such as Salmonella spp., Vibrio cholerae, Pseudomonas aeruginosa and Enterotoxigenic E. coli (ETEC)
Agar media, 23 isolates were found, all the isolates produced small, irregular and round shape with shiny whitish cream or brownish colored which were morphologically similar to Lactobacillus spp. and among these isolets only 4 isolates were selected for further study according to their growth inhibition properties against four references pathogenic microorganisms Salmonella spp., Vibrio cholerae, Pseudomonas aeruginosa and Enterotoxigenic E. coli (ETEC)
Summary
Lactobacillus is one of the most important genera of lactic acid bacteria (LAB) (Coeuret et al, 2003). Lactobacillus spp. are widely used as probiotics which play a key role in enhancing resistance to colonization by exogenous, potentially, pathogenic organisms in the intestinal tract. They produce a variety of substances e.g., bacteriocin, nisin, lacticin etc. That are effective against different types of enteric pathogens like Escherichia coli, Salmonella spp., Shigella spp., Vibrio spp., Bacillus spp., Klebsiella spp., Staphylococcus spp., Pseudomonas spp., Proteus spp. etc. These effects can be described as the improvement of lactose digestion and the treatment of diarrheal disorders (Abdullah and Osman, 2010). The present study was designed to characterize some Lactobacillus spp. from various goat milk samples collected from different regions of Chittagong district to investigate their optimum growth conditions, and some probiotic properties like sensitivity to antibiotics and antagonistic activity to pathogenic bacteria
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
