화학공학소재연구정보센터
Applied Biochemistry and Biotechnology, Vol.173, No.7, 1896-1906, 2014
Enhanced L-Lactic Acid Production from Biomass-Derived Xylose by a Mutant Bacillus coagulans
Xylose effective utilization is crucial for production of bulk chemicals from low-cost lignocellulosic substrates. In this study, an efficient l-lactate production process from xylose by a mutant Bacillus coagulans NL-CC-17 was demonstrated. The nutritional requirements for l-lactate production by B. coagulans NL-CC-17 were optimized statistically in shake flask fermentations. Corn steep liquor powder and yeast exact were identified as the most significant factors by the two-level Plackett-Burman design. Steepest ascent experiments were applied to approach the optimal region of the two factors, and a central composite design was employed to determine their optimal levels. The optimal medium was used to perform batch fermentation in a 3-l bioreactor. A maximum of 90.29 g l(-1) l-lactic acid was obtained from 100 g l(-1) xylose in 120 h. When using corn stove prehydrolysates as substrates, 23.49 g l(-1) l-lactic acid was obtained in 36 h and the yield was 83.09 %.