title: Formaldehyde stabilization facilitates lignin monomer production during biomass depolymerization.
abstract: Practical, high-yield lignin depolymerization methods could greatly increase biorefinery productivity and profitability. However, development of these methods is limited by the presence of interunit carbon-carbon bonds within native lignin, and further by formation of such linkages during lignin extraction. We report that adding formaldehyde during biomass pretreatment produces a soluble lignin fraction that can be converted to guaiacyl and syringyl monomers at near theoretical yields during subsequent hydrogenolysis (47 mole % of Klason lignin for beech and 78 mole % for a high-syringyl transgenic poplar). These yields were three to seven times those obtained without formaldehyde, which prevented lignin condensation by forming 1,3-dioxane structures with lignin side-chain hydroxyl groups. By depolymerizing cellulose, hemicelluloses, and lignin separately, monomer yields were between 76 and 90 mole % for these three major biomass fractions.
authors.affiliation: Laboratory of Sustainable and Catalytic Processing, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
authors.forename: Li
authors.initials: L
authors.lastname: Shuai
authors.affiliation: Laboratory of Sustainable and Catalytic Processing, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
authors.forename: Masoud Talebi
authors.initials: MT
authors.lastname: Amiri
authors.affiliation: Laboratory of Sustainable and Catalytic Processing, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
authors.forename: Ydna M
authors.initials: YM
authors.lastname: Questell-Santiago
authors.affiliation: Laboratory of Sustainable and Catalytic Processing, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
authors.forename: Florent
authors.initials: F
authors.lastname: Héroguel
authors.affiliation: U.S. Department of Energy (DOE) Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53726, USA.|Department of Biological Systems Engineering, University of Wisconsin, Madison, WI 53706, USA.
authors.forename: Yanding
authors.initials: Y
authors.lastname: Li
authors.affiliation: U.S. Department of Energy (DOE) Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53726, USA.|Department of Biochemistry, University of Wisconsin, Madison, WI 53706, USA.
authors.forename: Hoon
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Meilan
authors.affiliation: Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Clint
authors.initials: C
authors.lastname: Chapple
authors.affiliation: U.S. Department of Energy (DOE) Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53726, USA.|Department of Biological Systems Engineering, University of Wisconsin, Madison, WI 53706, USA.|Department of Biochemistry, University of Wisconsin, Madison, WI 53706, USA.
authors.forename: John
authors.initials: J
authors.lastname: Ralph
authors.affiliation: Laboratory of Sustainable and Catalytic Processing, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland. jeremy.luterbacher@epfl.ch.
authors.forename: Jeremy S
authors.initials: JS
authors.lastname: Luterbacher
mesh_terms: D002384:Catalysis; D002482:Cellulose / Q000737:chemistry; D005591:Chemical Fractionation; D005557:Formaldehyde / Q000737:chemistry*; D008031:Lignin / Q000096:biosynthesis* / Q000737:chemistry; D030821:Plants, Genetically Modified / Q000737:chemistry / Q000235:genetics; D058105:Polymerization; D011134:Polysaccharides / Q000737:chemistry; D032107:Populus / Q000737:chemistry / Q000235:genetics
chemical_list: D011134:Polysaccharides; D005557:Formaldehyde; C007916:hemicellulose; D002482:Cellulose; D008031:Lignin