title: Characterization of Lactobacillus isolated from dairy samples for probiotic properties.
abstract: In the present study twelve Lactobacillus isolates (LBS 1-LBS 12) were characterized for probiotic properties. Out of the twelve, eight isolates (LBS 1-6, 8 and 11) were bile resistant (survival > 50% at 0.3% bile salt w/v) and five isolates (LBS 1, 2, 5, 6 and 11) were found acid pH value resistant (survival > 50% at pH 3). All twelve isolates inhibited the growth of Staphylococcus aureus whereas isolate LBS 2 also inhibited the growth of Escherichia coli and Salmonella typhimurium. Antibiotic susceptibility testing of isolates was also performed and isolate LBS 2 was selected for further study based on its broad spectrum effect in clinical pathogen inhibition. LBS 2 was characterized phenotypically at Institute of Microbial Technology (IMTECH), Chandigarh, India and was confirmed as Lactobacillus rhamnosus by 16S rDNA sequencing and subsequent analysis using BLAST. The gene sequence was deposited in GenBank with accession number KJ562858. Scanning electron microscopy (SEM) study was used to study in vitro epithelial cell adherence and bile salt effect on isolate LBS 2. Epithelial cells adherence assay showed positive results and surface roughness of LBS 2 increased with increase in bile salt (0.15-0.45% w/v).
authors.affiliation: School of Bioengineering and Food Technology, Shoolini University of Biotechnology and Management Sciences, Solan 173212, H.P., India.
authors.forename: Ashwani
authors.initials: A
authors.lastname: Kumar
authors.affiliation: School of Bioengineering and Food Technology, Shoolini University of Biotechnology and Management Sciences, Solan 173212, H.P., India. Electronic address: dineshkumar@shooliniuniversity.com.
authors.forename: Dinesh
authors.initials: D
authors.lastname: Kumar
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001422:Bacterial Adhesion; D001647:Bile Acids and Salts / Q000494:pharmacology; D003611:Dairy Products / Q000382:microbiology*; D004847:Epithelial Cells / Q000382:microbiology; D005516:Food Microbiology; D005838:Genotype; D006801:Humans; D007778:Lactobacillus / Q000145:classification / Q000187:drug effects / Q000302:isolation & purification* / Q000502:physiology; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects; D010641:Phenotype; D010802:Phylogeny; D019936:Probiotics; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001647:Bile Acids and Salts; D012336:RNA, Ribosomal, 16S
keywords: 16S rDNA amplification; Epithelial cell adherence; Isolate LBS 2; Lactobacillus characterization; SEM