Fast Enzymatic Saccharification of Switchgrass After Pretreatment with Ionic Liquids
- Argonne National Laboratory (ANL)
- ORNL
- Savannah State University
The pretreatment of cellulose using ionic liquids (ILs) has been shown to be an effective method for improving the enzymatic hydrolysis of cellulose; this technique affords a fast and complete saccharification of cellulose into reducing sugars (Dadi et al., Biotechnol Bioeng. 2006; 95:904 910; Liu and Chen, Chinese Sci Bull. 2006; 51:2432 2436; Zhao et al., J Biotechnol. 2009; 139:47 54). Motivated by these advances, this study examines the effect of IL-pretreatment on the enzymatic hydrolysis of purified xylan (as a model system of hemicellulose) and switchgrass (as a real lignocellulose). The IL-pretreatment resulted in no improvement in the hydrolysis of xylan. The likely reason is that pure xylan has a low degree of polymerization (DP), and is readily biodegraded even without any pretreatment. However, in real cellulosic materials (such as switchgrass), xylan is entrapped within the cellulosic matrix, and cannot be conveniently accessed by enzymes. Our data demonstrate that the IL-pretreatment of switchgrass significantly improved the enzymatic saccharification of both cellulose (96% D-glucose yield in 24 h) and xylan (63% D-xylose yield in 24 h). The compositional analysis of switchgrass suggests a lower lignin content after IL-pretreatment. In addition, the infrared spectrum of regenerated switchgrass indicates a lower substrate crystallinity, whereas the enzyme adsorption isotherm further implies that the regenerated substrate is more accessible to enzymes. This study has further confirmed that ILpretreatment is an effective tool in enhancing the enzymatic hydrolysis of cellulosic biomass, and allowing a more complete saccharification.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- DE-AC05-00OR22725
- OSTI ID:
- 1078189
- Journal Information:
- Biotechnology Progress, Vol. 26, Issue 1
- Country of Publication:
- United States
- Language:
- English
Similar Records
Comparison of enzymatic reactivity of corn stover solids prepared by dilute acid, AFEX™, and ionic liquid pretreatments
Ternary ionic liquid–water pretreatment systems of an agave bagasse and municipal solid waste blend