Simultaneous detoxification, saccharification and co-fermentation of oil palm empty fruit bunch hydrolysate for L-lactic acid production by Bacillus coagulans JI12

摘要

Bacillus coagulans J11 2 was used to produce L-lactic acid from both cellulose and hemicellulose sugars of oil palm empty fruit bunch hydrolysate at 50 = C without sterilization prior to fermentation. In fermentation of mixed glucose and xylose (10g/L:100g/L or 50g/L:53 g/L), both sugars were simultaneously converted to L-lactic acid. B. coagulans JI12 was tolerant against up to 4 g/L of furfural and 20 g/L of acetate and able to metabolize furfural to 2-furoic acid. After acid hydrolysis, both the hemicellulosic and cellulosic fractions of oil palm empty fruit bunch were fermented to lactic acid in a simultaneous detoxification, saccharification and co-fermentation process supplemented with 25 FPU Cellic? CTec2 cellulase per g cellulose, yielding 80.6 g/L of lactic acid with a productivity of 3.4g/L/h. Neither pre-detoxification nor separation of fermentable sugars from lignin was required. These results indicate that B. coagulans JI12 is a promising strain for L-lactic acid production from lignocellulosic biomass.