title: Biological valorization of low molecular weight lignin.
abstract: Lignin is a major component of lignocellulosic biomass and as such, it is processed in enormous amounts in the pulp and paper industry worldwide. In such industry it mainly serves the purpose of a fuel to provide process steam and electricity, and to a minor extent to provide low grade heat for external purposes. Also from other biorefinery concepts, including 2nd generation ethanol, increasing amounts of lignin will be generated. Other uses for lignin - apart from fuel production - are of increasing interest not least in these new biorefinery concepts. These new uses can broadly be divided into application of the polymer as such, native or modified, or the use of lignin as a feedstock for the production of chemicals. The present review focuses on the latter and in particular the advances in the biological routes for chemicals production from lignin. Such a biological route will likely involve an initial depolymerization, which is followed by biological conversion of the obtained smaller lignin fragments. The conversion can be either a short catalytic conversion into desired chemicals, or a longer metabolic conversion. In this review, we give a brief summary of sources of lignin, methods of depolymerization, biological pathways for conversion of the lignin monomers and the analytical tools necessary for characterizing and evaluating key lignin attributes.
authors.affiliation: Department of Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
authors.forename: Omar Y
authors.initials: OY
authors.lastname: Abdelaziz
authors.affiliation: Department of Chemistry, Applied Microbiology, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Brink
authors.affiliation: Department of Chemistry, Centre for Analysis and Synthesis, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
authors.forename: Jens
authors.initials: J
authors.lastname: Prothmann
authors.affiliation: Department of Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
authors.forename: Krithika
authors.initials: K
authors.lastname: Ravi
authors.affiliation: Department of Chemistry, Centre for Analysis and Synthesis, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
authors.forename: Mingzhe
authors.initials: M
authors.lastname: Sun
authors.affiliation: Department of Chemistry, Applied Microbiology, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
authors.forename: Javier
authors.initials: J
authors.lastname: García-Hidalgo
authors.affiliation: Department of Chemistry, Centre for Analysis and Synthesis, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
authors.forename: Margareta
authors.initials: M
authors.lastname: Sandahl
authors.affiliation: Department of Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
authors.forename: Christian P
authors.initials: CP
authors.lastname: Hulteberg
authors.affiliation: Department of Chemistry, Centre for Analysis and Synthesis, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
authors.forename: Charlotta
authors.initials: C
authors.lastname: Turner
authors.affiliation: Department of Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden. Electronic address: gunnar.liden@chemeng.lth.se.
authors.forename: Gunnar
authors.initials: G
authors.lastname: Lidén
authors.affiliation: Department of Chemistry, Applied Microbiology, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
authors.forename: Marie F
authors.initials: MF
authors.lastname: Gorwa-Grauslund
mesh_terms: D055162:Biocatalysis; D056804:Biofuels; D018533:Biomass; D001709:Biotechnology; D008031:Lignin; D008970:Molecular Weight; D058105:Polymerization; D059027:Recycling
chemical_list: D056804:Biofuels; D008031:Lignin
keywords: Aromatic metabolism; Biochemical conversion; Biorefinery; Catalysis; Chromatography; Depolymerization; Lignin; Lignocellulose; Mass spectrometry