Optimisation of significant features on lactic acid and lactase enzyme production in mineral salts medium by L. bifermentans

The aim of this work was to study the fermentation of lactose substrate in mineral salts medium for the production of L(+) lactic acid and lactase enzyme using Lactobacillus bifermentum. The effect of different process parameters such as various lactose concentration, pH of the medium, temperature and inoculum concentration was monitored to enhance the lactose conversion into lactase and lactic acid. Fermentations were performed in batch mode method with suitable environment. The optimization of the fermentation conditions resulted in significant decrease in fermentation time, besides increase in lactose conversion to lactic acid and lactase. The optimized process conditions resulted in high lactic acid production (1740mg/L) and high lactase enzyme production (2.91ALU) at 0.5% lactose, 1% inoculum, pH6 and temperature 30oC.