Extraction of Bacteriocin and Study of Its Antigonastic Assay

摘要

Bacteriocins are antimicrobial, proteinaceous substances, ribosomally synthesized, secreted bactericidal peptides. Here, the bacteriocins have been extracted from the lactic acid bacteria. The source used for isolation of lactic acid bacteria was "yogurt and idli batter". By simple methodology bacteriocin was extracted from the isolated and cultured organisms, it was then purified by precipitating the extract with ammonium sulfate at various saturations. The purpose of bacteriocin extraction from lactic acid bacteria is that, lactic acid bacteria are found as human flora and are widely used for fermentation and preservation of food from spoilage thus, becomes a natural method of extending the shelf life of food. Nisin is the most commonly used commercial bacteriocin as a bioprservative which makes us to avoid the harmful chemical preservatives. To demonstrate their production,we overlayed each plate soft agar (Muller Hinton Agar) with one of the indicator strains and, well diffusion method using the purified sample, was performed. The presence and action of bacteriocins was inferred by zones of growth inhibition around the wells.