Characterization and Antibacterial Activity of Bacteriocin Producing Lactobacillus Isolated from Raw Cattle Milk Sample

Abstract

The intent of the study is to determine the antimicrobial activity of Lactobacillus producing bacteriocin isolated from raw milk of cattle's like cow, buffalo and goat and to characterize the bacteriocin. Hundred Lactobacillus isolates (50 isolates from cow, 22 isolates from buffalo and 28 isolates from goat) based upon the distinct morphology were isolated from the samples and identified as Lactobacilli according to phenotypic characteristics. Bacteriocin producing organisms were screened by Agar spot assay test. Ten strains were able to produce bacteriocin whose antibacterial activity was analyzed by agar well diffusion assay test against indicator organisms and pathogenic organisms. Bacillus mycoides, Staphylococcus aureus, Streptococcus faecalis, Klebsiella pnuemoniae and Proteus vulgaris were inhibited by the isolates. Bacillus amyloliquifaciens, Bacillus cereus, Salmonella typhi and Pseudomonas aeruginosa, were resistant to the isolates producing antibacterial substances. The antibacterial protein bacteriocin was characterized based on the sensitivity to heat, different pH values, acid neutralization test, sensitivity to chloroform, NaCl and incubation period. Lactobacilli from raw milk samples that inhibited certain pathogenic organisms by producing bacteriocin may be beneficial for a probiotic culture to be triumphant in colonizing and to contend with pathogens.

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Identificación Y Caracterización Molecular De Cepas Nativas De Lactobacillus Aisladas De Material De Cama De Pollos De Engorde

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