Visualization of biomass solubilization and cellulose regeneration during ionic liquid pretreatment of switchgrass
Article first published online: 4 MAY 2009
This article is a U.S. Government work and is in the public domain in the U.S.A. Published in 2009 by John Wiley & Sons, Ltd.
Biotechnology and Bioengineering
Volume 104, Issue 1, pages 68–75, 1 September 2009
How to Cite
Singh, S., Simmons, B. A. and Vogel, K. P. (2009), Visualization of biomass solubilization and cellulose regeneration during ionic liquid pretreatment of switchgrass. Biotechnol. Bioeng., 104: 68–75. doi: 10.1002/bit.22386
- Issue published online: 20 JUL 2009
- Article first published online: 4 MAY 2009
- Accepted manuscript online: 4 MAY 2009 12:00AM EST
- Manuscript Accepted: 27 APR 2009
- Manuscript Revised: 17 APR 2009
- Manuscript Received: 4 MAR 2009
- ionic liquids;
Auto-fluorescent mapping of plant cell walls was used to visualize cellulose and lignin in pristine switchgrass (Panicum virgatum) stems to determine the mechanisms of biomass dissolution during ionic liquid pretreatment. The addition of ground switchgrass to the ionic liquid 1-n-ethyl-3-methylimidazolium acetate resulted in the disruption and solubilization of the plant cell wall at mild temperatures. Swelling of the plant cell wall, attributed to disruption of inter- and intramolecular hydrogen bonding between cellulose fibrils and lignin, followed by complete dissolution of biomass, was observed without using imaging techniques that require staining, embedding, and processing of biomass. Subsequent cellulose regeneration via the addition of an anti-solvent, such as water, was observed in situ and provided direct evidence of significant rejection of lignin from the recovered polysaccharides. This observation was confirmed by chemical analysis of the regenerated cellulose. In comparison to untreated biomass, ionic liquid pretreated biomass produces cellulose that is efficiently hydrolyzed with commercial cellulase cocktail with high sugar yields over a relatively short time interval. Biotechnol. Bioeng. 2009; 104: 68–75 Published 2009 Wiley Periodicals, Inc.