Lactobacillus

A very common probiotic bacterium is Lactobacillus. In the current study for the first time the isolation has been done from Sperata seenghala and Labeo bata. The objective of the current study was to isolate and identify Lactobacillus bacteria from the intestines of these two fishes. The total bacterial counts were 2.1x106 and 1.8x105 CFU/g. Isolation was done by dissection, homogenization and filtration. The isolates were identified as Lactobacillus by gram staining, microscopic observation and biochemical tests. The isolates showed growth within pH 3 to 8 with maximum growth at pH 7. They stood firm at bile salt concentrations of 0.0, 0.1, 0.2 and 0.3%. Antibiotic sensitivity test was done by disc diffusion method. The Lactobacillus isolated from S. seenghala was resistant to Ampicillin, Ceftazidime, Cefuroxime, Co-trimoxazole and Nalidixic Acid. Isolate from L. bata was resistant to Ampicillin, Azithromycin, Ceftazidime, and Cloxacillin. Both these isolates can be denoted as potential probiotics and they will serve as very useful tools for future research.

Urinary tract infections (UTIs) are the most frequent community-acquired infections in world wide. The antimicrobial activity lactobacillus and its bacteriocins production were studied. A total 25 isolates were obtained from 35 urine samples. The most recurrently encountered pathogens were E. coli (9) 25.71%, Klebsiella pneumonia (7) 20%, Proteus mirabilis (4) 11.42%, Pseudomonas aeruginosa(4) 11.42%, and Candida albicans 1(2.8%) respectively. It was observed that the lactobacillus sp effectively inhibit the UTI pathogen such as E.coli, Klebsiella pneumonia, Pseudomonas aeruginosa, Proteus mirabilis and Candida albicans. Based on antimicrobial activity, the potential strains were selected for optimization of bacteriocin activity at different temperature and pH value. The effect of NaCl on bacteriocin activity was also studied. It was clearly noted that theLactobacillus showed very strong inhibition against Pseudomonas aeruginosa (15.5mm) and Klebsiella pneumonia (13.2mm), strong inhibition against Proteus mirabilis (12.1mm)and moderate inhibition against Escherishia coli (10mm) and Candida albicans (10.0mm). The activity of bacteriocin was stable between the pH 4.0 to 5.0 and it didn’t show any antimicrobial activity above pH 5.0. The activity of bacteriocin was stable at temperature less than 800C and above 1% NaCl concentration increased the production of bacteriocin from 25-75%. Thus the above study indicates that Lactobacillus can be used as a alternative therapy to treat the UTI infection and to overcome the emergency of rapid increase of drug resistance UTI pathogens. Key words: Urinary tract infection, Lactobacillus, Antimicrobial activity, bacteriocin.