title: Effect of ionic liquid pretreatment on the chemical composition, structure and enzymatic hydrolysis of energy cane bagasse.
abstract: Ionic liquids (ILs) are promising solvents for the pretreatment of lignocellulose as they are thermally stable, environmentally friendly, recyclable, and have low volatility. This study evaluated the effect of 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]) for the pretreatment of energy cane bagasse in terms of biomass composition, structural changes and enzymatic digestibility. Energy cane bagasse was pretreated with [EMIM][OAc] (5% (w/w)) at 120 °C for 30 min followed by hydrolysis with commercially available enzymes, Spezyme CP and Novozyme 188. IL-treated energy cane bagasse resulted in significant lignin removal (32.0%) with slight glucan and xylan losses (8.8% and 14.0%, respectively), and exhibited a much higher enzymatic digestibility (87.0% and 64.3%) than untreated (5.5% and 2.8%) or water-treated (4.0% and 2.1%) energy cane bagasse in terms of both cellulose and hemicellulose digestibilities, respectively. The enhanced digestibilities of IL-treated biomass can be attributed to delignification and reduction of cellulose crystallinity as confirmed by FTIR and XRD analyses.
authors.affiliation: Audubon Sugar Institute, Louisiana State University Agricultural Center, Saint Gabriel, LA 70776, USA.
authors.forename: Zenghui
authors.initials: Z
authors.lastname: Qiu
authors.forename: Giovanna M
authors.initials: GM
authors.lastname: Aita
authors.forename: Michelle S
authors.initials: MS
authors.lastname: Walker
mesh_terms: D018533:Biomass; D001709:Biotechnology / Q000379:methods*; D002480:Cellulase / Q000378:metabolism; D002482:Cellulose / Q000737:chemistry* / Q000378:metabolism* / Q000648:ultrastructure; D003460:Crystallization; D006868:Hydrolysis / Q000187:drug effects; D007093:Imidazoles / Q000494:pharmacology; D052578:Ionic Liquids / Q000737:chemistry / Q000494:pharmacology*; D008031:Lignin / Q000737:chemistry; D011134:Polysaccharides / Q000378:metabolism; D031786:Saccharum / Q000737:chemistry* / Q000187:drug effects*; D017550:Spectroscopy, Fourier Transform Infrared; D014867:Water / Q000494:pharmacology; D014961:X-Ray Diffraction; D001617:beta-Glucosidase / Q000378:metabolism
chemical_list: D007093:Imidazoles; D052578:Ionic Liquids; D011134:Polysaccharides; D014867:Water; C036909:lignocellulose; C007916:hemicellulose; D002482:Cellulose; D008031:Lignin; C027433:bagasse; D001617:beta-Glucosidase; D002480:Cellulase; C518739:1-ethyl-3-methylimidazolium