Production of lactic acid and fructose from media with cane sugar using mutant of Lactobacillus delbrueckii NCIM 2365

Abstract

Aims: To examine the potential of Lactobacillus delbrueckii mutant, Uc-3 to produce lactic acid and fructose from sucrose-based media.

Methods and results: The mutant of L. delbrueckii NCIM 2365 was cultivated in shake flask containing hydrolysed cane sugar (sucrose)-based medium. The lactic acid yield and volumetric productivity with hydrolysed cane concentration up to 200 g l(-1) were in the range of 92-97% of the theoretical value and between 2.7 and 3.8 g l(-1) h(-1), respectively. The fructose fraction of the syrup produced was more than 95% when the total initial sugar concentration in the medium was higher (150-200 g l(-1)). There are no unwanted byproducts detected in the fermentation broth.

Conclusions: We demonstrated that L. delbrueckii mutant Uc-3 was able to utilize glucose preferentially to produce lactic acid and fructose from hydrolysed cane sugar in batch fermentation process.

Significance and impact of the study: These findings will be useful in the production of lactic acid and high fructose syrups using media with high concentrations of sucrose-based raw materials. This approach can lead to modification of the traditional fermentation processes to obtain value-added byproducts, attaining better process economics.