9-59: Performances of Lactobacillus brevis for producing lactic acid from hydrolysate of lignocellulosics

Utilizing all forms of sugars derived from lignocellulosic biomass via various pretreatment and hydrolysis process is a primary criterion for selecting a microorganism to produce biofuels and biochemicals.  With dilute acid hydrolysis technology, the broad carbon spectra and potential inhibitors such as furan, phenol compounds and weak acid to microorganism are the two major obstacles that limited the application of dilute-acid hydrolysate of lignocellulose in ethanol and lactic acid fermentation. Two strains S3F4 (Lactobacillus brevis) and XS1T3-4 (Lactobacillus plantrum) isolated from sour cabbage, exhibited the ability to utilize various sugars presented in dilute-acid hydrolysate of lignocellulose. The S3F4 strain also showed strong resistance ability to the potential fermentation inhibitors, ferulic acid and furfural. Shake-flask fermentation indicated that 39.1 g/l of lactic acid could be produced by S3F4 from dilute acid hydrolysates of corn cob with 56.9 g/l total sugars (xylose, 46.4 g/l; glucose, 4.0 g/l, arabinose, 6.5 g/l). The hydrolysate of corn cob could be readily utilized by S3F4 without detoxification, and the lactic acid concentration in the fermentation broth was higher compared to other reports.