author(s)
M Dhanalakshmi, V Bhanu Rekha, S Balakrishnan, A Sangeetha and T Dinesh Kumar

abstract
Lactic acid bacteria (LAB) are getting more attention now, since they are capable of producing bacteriocins with broad spectrum antimicrobial activity. Two common fermented traditional food in all south Indian food schedule are curd and idly mix (i.e. batter) were used as a source for LAB isolation on DeManRogosa Sharpe (MRS) agar. Crude bacteriocin Production by spot on lawn method and pure bacteriocin was extracted from the culture by solvent extraction method using chloroform. Bacteriocin assay was performed by with bacterial strains Bacillus cereus, Campylobacter jejuni, Escherichia coli, Listeria monocytogenes and Staphylococcus aureus. with crude bacteriocin, crude extract adjusted pH6, crude bacteriocin mixed with tween -80 for efficient diffusion, Solvent extracted bacteriocin and bacteriocin heat treated at 70 ⁰C. Solvent extracted bacteriocin has higher antimicrobial activity of 6.83 ±0.17, 5.67 ± 0.31, 6.17 ± 0.31, 6.83 ± 0.31 and 6.40 ± 0.26 respectively. Potent antimicrobial activity of this bacteriocin against all the five food borne organisms ensures the betterment of food industry.