DETECTION OF ANTIMICROBIAL EFFICASY OF NOVEL BACTERIOCIN PRODUCED FROM Lactobacillus similis RL7

Production of antimicrobial substances is often important trait in the context of bacterial fitness but also in terms of probiotic efficacy. Several probiotic bacteria produce a variety of antimicrobial compounds viz. short chain fatty acids, Hydrogen peroxide, Nitric oxide, Bacteriocins etc. Bacteriocins are peptide or protein complexes showing antibacterial activity against closely related species. These antimicrobial agents are gaining more and more attention as an alternative therapeutics not only in pharmaceutical but also as a preservative in food industries. In present study, bacteriocin production was carried out by Lactobacillus similis RL 7 isolated from rose inner petals and identified by 16s rRNA sequence analysis. This newly isolated strain showed antibacterial activity against several Gram positive and Gram negative bacteria. To obtain maximum bacteriocin yield, Production study was carried out in three different production media viz. MRS broth, BSM broth and M17 medium. An isolate RL 7 showed the maximum bacteriocin production in MRS medium. The produced bacteriocin was purified by Ammonium Sulphate and RP – HPLC method. Molecular mass determination study was done by SDS – PAGE and it was found that, the new bacteriocin having molecular weight less than 6.4 KDa was observed. Bacteriocin from Lactobacillus similis RL 7 is capable of capable of showing antimicrobial activity at wide range of temperatures and pH but lost activity in presence of proteolytic enzymes. Hence Lactobacillus similis RL 7 it is an ideal strain for bacteriocin production for food and pharmaceutical industries.