title: Some probiotic and antibacterial properties of Lactobacillus acidophilus cultured from dahi a native milk product.
abstract: In this study, different strains of Lactobacillus acidophilus from dahi were analyzed for certain probiotic and antibacterial properties. Initially, these strains were confirmed by the amplification of 16S rRNA regions and then screened for antibacterial activities against food borne pathogens. The phenotypic relationship between apparent antibacterial activity and cell wall proteins were established by cluster analysis. It was observed that those strains, which have prominent bands having size 22-25 kDa possess antibacterial activity. On the basis of wide spectrum of killing pattern, a strain LA06FT was further characterized that showed no change in its behavior when subjected to the antibiotic protected environment and grow well in acid-bile conditions. The bacteriocin produced by this strain has specific antibacterial activity of 5369.13 AU mg(-1). It remained stable at 60-90 °C and pH range of 4.5-6.5 while proteolytic enzymes inactivate the bacteriocin that confirm its proteinic nature having molecular weight of ≤8.5 kDa.
authors.affiliation: Department of Food Technology, Pir Mehr Ali Shah Arid Agriculture University , Rawalpindi , Pakistan.
authors.forename: Talat
authors.initials: T
authors.lastname: Mahmood
authors.forename: Tariq
authors.initials: T
authors.lastname: Masud
authors.forename: Asma
authors.initials: A
authors.lastname: Sohail
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001430:Bacteriocins / Q000096:biosynthesis / Q000494:pharmacology; D016000:Cluster Analysis; D003611:Dairy Products / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D007779:Lactobacillus acidophilus; D008970:Molecular Weight; D019936:Probiotics / Q000008:administration & dosage*; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D012336:RNA, Ribosomal, 16S
keywords: Antibacterial activity; Lactobacillus acidophilus; SDS-PAGE; dahi; plasmid profile; probiotic culture