Lignin biodegradation and industrial implications

Adam B Fisher; Stephen S Fong; Adam B Fisher; Stephen S Fong

doi:10.3934/bioeng.2014.2.92

AIMS Bioengineering

2014, Volume 1, Issue 2: 92-112. doi: 10.3934/bioeng.2014.2.92

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Review Special Issues

Lignin biodegradation and industrial implications

Adam B Fisher ¹,
Stephen S Fong ^{1,2
,
,}

1.
Integrative Life Sciences Program, School of Life Sciences, Virginia Commonwealth University, Richmond, Virginia
2.
Systems Biological Engineering Laboratory, Department of Chemical and Life Science Engineering, Virginia Commonwealth University, Richmond, Virginia E-mail: ssfong@vcu.edu

Received: 28 October 2014 Accepted: 04 December 2014 Published: 11 December 2014

Lignocellulose, which comprises the cell walls of plants, is the Earth’s most abundant renewable source of convertible biomass. However, in order to access the fermentable sugars of the cellulose and hemicellulose fraction, the extremely recalcitrant lignin heteropolymer must be hydrolyzed and removed—usually by harsh, costly thermochemical pretreatments. Biological processes for depolymerizing and metabolizing lignin present an opportunity to improve the overall economics of the lignocellulosic biorefinery by facilitating pretreatment, improving downstream cellulosic fermentations or even producing a valuable effluent stream of aromatic compounds for creating value-added products. In the following review we discuss background on lignin, the enzymology of lignin degradation, and characterized catabolic pathways for metabolizing the by-products of lignin degradation. To conclude we survey advances in approaches to identify novel lignin degrading phenotypes and applications of these phenotypes in the lignocellulosic bioprocess.
- lignin,
- lignocellulose,
- ligninolytic,
- biofuels,
- biorefinery,
- bioprospecting,
- aromatics
Citation: Adam B Fisher, Stephen S Fong. Lignin biodegradation and industrial implications[J]. AIMS Bioengineering, 2014, 1(2): 92-112. doi: 10.3934/bioeng.2014.2.92

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Abstract

Lignocellulose, which comprises the cell walls of plants, is the Earth’s most abundant renewable source of convertible biomass. However, in order to access the fermentable sugars of the cellulose and hemicellulose fraction, the extremely recalcitrant lignin heteropolymer must be hydrolyzed and removed—usually by harsh, costly thermochemical pretreatments. Biological processes for depolymerizing and metabolizing lignin present an opportunity to improve the overall economics of the lignocellulosic biorefinery by facilitating pretreatment, improving downstream cellulosic fermentations or even producing a valuable effluent stream of aromatic compounds for creating value-added products. In the following review we discuss background on lignin, the enzymology of lignin degradation, and characterized catabolic pathways for metabolizing the by-products of lignin degradation. To conclude we survey advances in approaches to identify novel lignin degrading phenotypes and applications of these phenotypes in the lignocellulosic bioprocess.

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