Atypical ethanol production by carbon catabolite derepressed lactobacilli

• Published in: Bioresource technology Vol. 101; no. 22; pp. 8790 - 8797
• Main Authors: Kim, Jae-Han, Block, David E., Shoemaker, Sharon P., Mills, David A.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.11.2010; Elsevier
• Subjects: Biological and medical sciences; Biomass; Biotechnology; Carbohydrate Metabolism - physiology; Carbon; Carbon catabolite repression; Ethanol; Ethanol - isolation & purification; Ethanol - metabolism; Ethyl alcohol; Fermentation; Fundamental and applied biological sciences. Psychology; Glucose; Hydrolysis; Lactobacillus; Lactobacillus - classification; Lactobacillus - metabolism; Lactobacillus pentosus; Lignocellulose; Metabolism; Methods. Procedures. Technologies; Microbial engineering. Fermentation and microbial culture technology; Oryza - microbiology; Oryza sativa; Plant Components, Aerial - microbiology; Plant Extracts - metabolism; Simultaneous saccharification and mixed-sugar fermentation; Species Specificity; Straw; Sugars; Lactobacillus pentosus; Carbon catabolite repression; Ethanol; Lignocellulose; Simultaneous saccharification and mixed-sugar fermentation; Simultaneous saccharification and mixed; Saccharification; Lignocellulosics; Repression; Fermentation; Carbon; sugar fermentation; Catabolite; Bacteria; Lactobacillaceae; Sugar; Lactobacillus
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2010.06.087

Cost effective use of lignocellulosic biomass for bio-based chemical production requires the discovery of novel strains and processes. Lactobacillus pentosus JH5XP5 is a carbon catabolite repression negative mutant which utilizes glucose and pentoses derived from lignocellulosic biomass in the media simultaneously. With a broad range of carbon substrates, L. pentosus JH5XP5 produced a significant amount of ethanol without acetate formation. The yields of ethanol were 2.0- to 2.5-fold higher than those of lactate when glucose, galactose or maltose was used either as a single carbon source or simultaneously with glucose. L. pentosus JH5XP5 was successfully used in an integrated process of simultaneous saccharification and mixed sugar fermentation of rice straw hydrolysate. During the fermentation, the enzyme activities for the saccharification of cellulose were not diminished. Moreover glucose, xylose, and arabinose sugars derived from rice straw hyrolysate were consumed concurrently as if a single carbon source existed and no sugars or cellulosic fiber remained after the fermentation.