Mutagenic influence of methyl benzenesulphonate on lactic acid bioproduction from sucrose by Lactobacillus bulgaricus BS-18

The present investigation highlights the mutagenic influence of methyl benzenesulphonate (MBS) on lactic acid bioproduction from sucrose by Lactobacillus bulgaricus BS-18. Mutagenesis has long been considered a powerful tool for enhancing microbial strains toward improved bioprocess efficiency. In this study, cultures of L. bulgaricus BS-18 were exposed to graded concentrations of MBS to induce random mutations and subsequently screened for enhanced lactic acid productivity. The mutagentreated strains exhibited significant variations in growth kinetics, sugar utilization, and lactic acid yield compared to the wild-type strain. Among the mutants obtained, several isolates demonstrated higher tolerance to substrate concentration and improved metabolic efficiency, thereby producing elevated lactic acid titers. Optimization of fermentation parameters such as pH, temperature, inoculum density, and sucrose concentration further enhanced production levels. The study establishes MBS mutagenesis as a viable strategy for strain improvement in lactic acid fermentation. The findings contribute to the development of efficient microbial platforms for industrial-scale lactic acid bioproduction, with potential applications in food, pharmaceutical, and biodegradable polymer industries. It has been observed that the mutagene MBS at concentration 0.4% enhances the yield of lactic acid by Lactobacillus bulgaricus BS18 to an extent of 14.544% higher in comparison to control under optimized conditions.