Location: Bioenergy ResearchTitle: Maleic acid treatment of biologically detoxified corn stover liquor
|KIM, DAEHWAN - Purdue University|
|XIMENES, EDUARDO - Purdue University|
|CAO, GUANGLI - Harbin Institute Of Technology (HIT)|
|LADISCH, MICHAEL - Purdue University|
Submitted to: Bioresource Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/21/2016
Publication Date: 6/6/2016
Citation: Kim, D., Ximenes, E.A., Nichols, N.N., Cao, G., Frazer, S.E., Ladisch, M.R. 2016. Maleic acid treatment of biologically detoxified corn stover liquor. Bioresource Technology. 216:437-445. doi: 10.1016/j.biortech.2016.05.086.
Interpretive Summary: Agricultural residues such as corn stover are suitable candidates for production of renewable fuels and chemicals because of their potential availability on an industrial scale at low cost. This study examined ways to improve the biomass-to-biofuels process, seeking to increase activity of enzymes by removing the various substances that inhibit the process. A combination of treatments yielding nearly three-fold higher conversion of corn stover to glucose were identified. Why this matters: enzymes are a significant cost of making renewable fuels and chemicals from biomass, so improving the activity of enzymes used in the process could decrease the input cost for biofuels.
Technical Abstract: Elimination of microbial and/or enzyme inhibitors from pretreated lignocellulose is critical for effective cellulose conversion and yeast fermentation of liquid hot-water (LHW) pretreated corn stover. In this study, xylan oligomers were hydrolyzed using either maleic acid or hemicellulases. Other soluble inhibitors were eliminated by biological abatement followed by ethanol fermentation using Saccharomyces cerevisiae NRRL Y-1546. Corn stover at 20% (w/v) solids was pretreated with LHW (severity factor: 4.3). The liquor was recovered and abated using the fungus Coniochaeta ligniaria NRRL30616. After maleic acid treatment, higher conversions of cellulose from Solka Floc and corn stover (22 and 73%, respectively) using 5 filter paper units of cellulase/g glucan (8.3 mg protein/g glucan) were obtained for bioabated samples compared to the values for the non-bioabated samples. Ethanol production of pretreated corn stover solids hydrolysate was 1.4 times higher than non-bioabated samples, with a reduction of 3 hours in the fermentation lag phase.