Enhanced L-lactic acid production from biomass-derived xylose by a mutant Bacillus coagulans

Appl Biochem Biotechnol. 2014 Aug;173(7):1896-906. doi: 10.1007/s12010-014-0975-2. Epub 2014 May 31.

Abstract

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 %.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacillus / genetics*
  • Bacillus / metabolism*
  • Biomass*
  • Bioreactors / microbiology
  • Biotechnology / methods*
  • Fermentation
  • Lactic Acid / biosynthesis*
  • Lignin / metabolism
  • Mutation*
  • Xylose / metabolism*
  • Zea mays / chemistry

Substances

  • lignocellulose
  • Lactic Acid
  • Lignin
  • Xylose