Sunday Times News: Lactobacillus is a kind of bacteria which can convert a sugar into an alcohol and then into an acid by means of anaerobic respiration. The Times of India News App for Latest Sunday Times News, Copyright Â© 2020 Bennett, Coleman & Co. Ltd. All rights reserved.  identified chick isolate of L. fermentum by phenotypic characterization. Curd is loaded with good nutrients like protein and calcium and can work wonderfully for people who are lactose intolerant and hence can’t have milk.  isolated LAB, from curd samples, which were Grampositive non-spore forming catalase negative strains characteristic to Lactobacillus. The culture of the isolates on MRS agar without antibiotic under similar conditions was used as the control. The L. fermentum 141 strain showed resistance to AM, nalidixic acid (NA), GM and cotrimoxazole, while L. fermentum 156 strain had resistance to the all antibiotics tested except AM, CP and cefpodoxime (CD), and L. casei 297 strain showed resistance to AM, NA, CP, GM, CD, cotrimoxazole and TC . The lactobacilli were considered sensitive, resistant or intermediately susceptible to the antibiotics for MICs <8, ≥8 or >32 μg/ml, respectively . Screening of potential probiotic properties of, Detection of intestinal colonization of probiotic. It takes about a day to form curd at room temperature. J Dairy Sci 88: 55-66.
Appl Environ Microbiol 73: 730-739. Growth of lactobacilli in MRS broth without bile salt was used as control. Shah  isolated lactobacilli strains, such as L. acidophilus and L. casei, on MRSsorbitol agar.
slow change c. chemical change d. All of these, synthesis of protein takes place in1. The L. fermentum 156 and L. casei 297 strains grew well in MRS broth (pH 2-3.5), while L. fermentum 141 strain survived in the same medium at pH 2-3.5 .
Acid tolerance of the isolated lactobacilli was determined by incubating (at 37°C for 24 h) each of the strains in MRS broth (Hi- Media, India) at various pH (2, 3 and 4), adjusted with 2% HCl. a Produce gas from glucose; b No gas production from glucose. Curd lactobacilli; Probiotics; Bile tolerance; Low-pH tolerance; Antibiogram. The isolated LAB were subjected for gram-staining (using gram-staining kits; Hi-Media, India), catalase (using 3% H2O2 on glass slide), oxidase (using oxidase discs; Hi-Media, India) and motility tests; homo-fermentative and hetero-fermentative tests were performed in TSI agar slants as well as in sugar fermentation broth , with durham’s tube but replacing sorbitol by dextrose discs (Hi-Media, India).
In the West Bengal state (India) mainly two types of curds (sweet curd and sour curd) are consumed by the people, and in our study two lactobacilli strains were isolated from sour curd samples that generally prepared with a little high salt concentration, and hence the isolated L. fermentum and L. casei strains getting pre-exposed to salts were protected from the stress of bile and temperature (42 °C), and thus survived well in MRS broth supplemented with 0.3% bile salts. Probiotics: A review. Two, among the 10, showed negative test results for indole and H2S production and citrate utilization, and were designated as Lactobacillus fermentum (n=1) and Lactobacillus casei (n=1) following sugar fermentation test results (Table 1); the strains grew well at 42°C, too.
12th International Conference on Predictive, Preventive and Personalized Medicine & Molecular Diagnostics, 2nd International Conference on Molecular Pathology and Genomics, Creative Commons Attribution 4.0 International License. A total of 10 curd samples (homemade and commercially available) were used in the study for the isolation of lactic acid bacteria (LAB). Asian Pac J Trop Biomed 1: S287-S290. Curd is made from milk which tastes sweet. ), Probiotics. Food Microbiol 17: 205-215. Background and Objectives: Lactobacilli are used as probiotics, but scientific investigation of such strains is scanty. 2015, 6:1. The antibiotic susceptibility test was performed for curd lactobacilli through the determination of minimum inhibitory concentration (MIC) values, by agar dilution method using approximately 104 CFU of inocula per spot on MRS agar plates, against ampicillin (AM), chloramphenicol (CH), ciprofloxacin (CP), cefotaxime (CF), gentamicin (GM) and tetracycline (TC); the other details are mentioned elsewhere (Mandal et al. Inoculation of MRS broth at various pH levels was done with L. fermentum and L. casei strains (10% vol/vol), after sub-culturing at least for twice; acid tolerance was indicated by the appearance of lactobacilli colonies on MRS agar after 24 h of spot inoculation of the MRS broth cultures of different pH condition. . In presence of 2% sodium chloride, the growth was observed for all the lactobacilli isolates (n=78), and with an increase of its concentration to 4%, growth of lactobacilli was observed for 38 isolates; however, no growth even for a single strain was noticed at the sodium chloride concentration of 6.5% . Considering bile tolerance an important characteristic of probiotic microorganisms, it has been reported that 0.3% oxgall closely appropriates the bile level of the human gastrointestinal tract, and the concentration of 0.3% bile salts has been considered crucial for screening and selection of human probiotics [25,26]. Five of these lactobacilli (Lb-17, Lb-33, Lb-108, Lb-112, and Lb-N3) were found most promising to inhibit all test pathogens (Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Salmonella typhiand Shigella sonnei). Antibacterial activity of honey against clinical isolates of, Antibiotic resistance of lactic acid bacteria and. The survival of the test lactobacilli strains (L. acidophilus, L. gasseri, L. rhamnosus and L. reuteri) ranged 0.01%-68.3% at pH 3, and 10.3%-57.4% at 0.15% bile salt concentration, as has been reported by Xanthopoulos et al.
Investigation of antibacterial, acid and bile tolerance properties of lactobacilli isolated from Koozeh cheese.
Bull Biosc 5: 10-14.
In various dairy products (cheese, yoghurt and curd) Lactobacillus are grown naturally.
Milk contains a sugar called lactose, a disaccharide (compound sugar) made by the glycosidic bonding between glucose and glactose (monosaccharides). Isolation and Identification of Lactic Acid Bacteria Isolated from Traditional Drinking yoghurt in Khartoum state, Sudan. Effect of lactic acid bacteria isolated from fermented mustard on immunopotentiating activity. The control comprised MRS broth without pH change. Characterization of Lactobacillus isolates from infant faeces as dietary adjuncts. The L. acidophilus strains were viable at different concentrations of bile salt and showed maximum growth at 0.2% bile; at 0.3% bile NCIM 2660 strain exhibited weak growth, and at higher concentration (0.5%), both NCIM 2660 and NCIM 2903 strains had negligible growth, and with regards to acid tolerance, the survival rates of all three strains were higher at 2 h incubation period than 4 h at pH 2.5 .
These convert the lactose into lactic acid, which imparts the sour taste to curd.
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