Improvement of Lactobacillus plantarum for the enhanced production of bacteriocin like inhibitory substance using combinatorial approach

Over the last few decades, emerging cases of chemical additives and food borne pathogens have enforced the demand of natural antimicrobial compounds. Bacteriocins are one of the natural alternatives to the chemical food preservatives. The research on new and improved bacteriocins is in full swing due to some limitations of commercially available bacteriocins. The aim of the study is to improve the indigenously isolated strain for the enhanced production of bacteriocin like inhibitory substance (BLIS) using combinatorial approach. In the current study, the efficiency of BLIS produced by Lactobacillus plantarum KIBGE-IB45 was improved by applying a combinatorial strategies. Primarily, production of BLIS was optimized using one factor at a time approach. To further enhance the potential of L. plantarum, chemical mutagens were used followed by statistical optimization using multivariate approach. The results revealed that synergistic effect of chemical mutagen and a sequential statistical optimization have significantly enhanced the production of BLIS at 35 °C in MRS medium with an initial pH 9.0 after 16 h of incubation. Response surface methodology revealed 2.0 fold increased in the production of BLIS. The ability of BLIS to inhibit the Listeria monocytogenes ATCC 7644 has enforced its application as a natural preservative to resolve the uncontrolled issues of food industry. •BLIS produced by L. plantarum has a bacteriocinogenic nature and capable of inhibiting L. monocytogenes.•Acridine orange has a potential to enhance BLIS production.•Conventional method of optimization (one-factor-at-a-time approach) does not lead to significant increase in BLIS production.•RSM was found to be the powerful tool of optimization and revealed 2.0 fold increase in the production of BLIS.•The ability of BLIS to inhibit the L. monocytogenes has enforced its application as a natural food preservative.