title: Fractionating recalcitrant lignocellulose at modest reaction conditions.
abstract: Effectively releasing the locked polysaccharides from recalcitrant lignocellulose to fermentable sugars is among the greatest technical and economic barriers to the realization of lignocellulose biorefineries because leading lignocellulose pre-treatment technologies suffer from low sugar yields, and/or severe reaction conditions, and/or high cellulase use, narrow substrate applicability, and high capital investment, etc. A new lignocellulose pre-treatment featuring modest reaction conditions (50 degrees C and atmospheric pressure) was demonstrated to fractionate lignocellulose to amorphous cellulose, hemicellulose, lignin, and acetic acid by using a non-volatile cellulose solvent (concentrated phosphoric acid), a highly volatile organic solvent (acetone), and water. The highest sugar yields after enzymatic hydrolysis were attributed to no sugar degradation during the fractionation and the highest enzymatic cellulose digestibility ( approximately 97% in 24 h) during the hydrolysis step at the enzyme loading of 15 filter paper units of cellulase and 60 IU of beta-glucosidase per gram of glucan. Isolation of high-value lignocellulose components (lignin, acetic acid, and hemicellulose) would greatly increase potential revenues of a lignocellulose biorefinery.
authors.affiliation: Biological Systems Engineering Department, Virginia Tech, Blacksburg, Virginia 24061, USA. ypzhang@vt.edu
authors.forename: Yi-Heng Percival
authors.initials: YH
authors.lastname: Zhang
authors.forename: Shi-You
authors.initials: SY
authors.lastname: Ding
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Mielenz
authors.forename: Jing-Biao
authors.initials: JB
authors.lastname: Cui
authors.forename: Richard T
authors.initials: RT
authors.lastname: Elander
authors.forename: Mark
authors.initials: M
authors.lastname: Laser
authors.forename: Michael E
authors.initials: ME
authors.lastname: Himmel
authors.forename: James R
authors.initials: JR
authors.lastname: McMillan
authors.forename: Lee R
authors.initials: LR
authors.lastname: Lynd
mesh_terms: D002482:Cellulose / Q000737:chemistry / Q000378:metabolism*; D005591:Chemical Fractionation / Q000379:methods*; D006868:Hydrolysis; D008031:Lignin / Q000378:metabolism*; D012997:Solvents / Q000737:chemistry
chemical_list: D012997:Solvents; C036909:lignocellulose; D002482:Cellulose; D008031:Lignin