R. K.PATHAK, H. BAROT, V. SHETTY, H. YUSUF AND N.E. PEREIRA
Abstract
The paper describes production of L(+) Lactic Acid by Lactobacillus delbrueckii in batch fermentation. Experiment shows that the lactic acid production by using Lactobacillus delbrueckii was successful and the bacteria took around 48 hours for the total conversion of reducible sugar into lactic acid. During fermentation, the reducible sugar content of the sample reduced from 9.81% to less than 1.47 % over a period of 48 hours. As the fermentation time increases Reducing sugar goes on decreasing, Calcium lactate yield increases gradually, yield increases to an maximum level and conversion also increase with increase in time. Selectivity showed mixed trends. It is observed that during the fermentation time (48 hours), almost all the reducing sugar was converted to calcium lactate. The wild strain of Lactobacillus delbrueckii takes about 96 â 120 hours for completion. However, the mutated strain was able to complete the fermentation process in about 48 hours. This proves that, the conversion time was reduced by more than 50% by non specific mutagenesis by exposing the wild type strain of Lactobacillus delbrueckii to Ultraviolet light for two minutes. The exact reason for the improvement cannot be pointed out since the genomic parts affected by exposure to ultraviolet light are unknown.