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Title: Characterization and enzymatic hydrolysis of wood from transgenic Pinus taeda engineered with syringyl lignin or reduced lignin content

Abstract

Softwood is an abundant resource; however, currently its utilization for bioconversion to obtain platform sugars is limited. Pinus taeda trees which were genetically modified to either produce S lignin or to decrease lignin content were characterized with a suite of analytic techniques. Syringyl lignin was visualized in the secondary xylem of one genetic line with Maule staining. Solid-state nuclear magnetic resonance identified the S lignin units were coupled into the lignin through β-O-4 linkages, and thioacidolysis measured approximately 13% S lignin content in the same sample. Reductions of the lignin of as much as 33% were observed in the transgenics. To better understand how these modifications affect bioconversion, their amenability to hot water and dilute acid pretreatments and enzymatic hydrolysis was evaluated. Lignin reductions resulted in 1.9-3.2-fold increases in glucose release compared to the control. However, no apparent benefit was observed by S lignin incorporation at the concentrations reported in this study. Finally, these results highlight the potential for softwood cell wall properties to be improved for bioenergy/biochemical applications.

Authors:
 [1];  [1];  [1];  [1];  [1];  [2];  [2];  [2];  [2];  [3];  [3];  [1];  [1]
  1. North Carolina State Univ., Raleigh, NC (United States)
  2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  3. ArborGen Inc., Ridgeville, SC (United States)
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE); USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
OSTI Identifier:
1347200
Report Number(s):
NREL/JA-2700-68109
Journal ID: ISSN 0969-0239
Grant/Contract Number:
AC36-08GO28308
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Cellulose
Additional Journal Information:
Journal Volume: 24; Journal Issue: 4; Journal ID: ISSN 0969-0239
Publisher:
Springer
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; softwood; lignin modification; lignocellulose; pyrolysis-molecular beam mass spectroscopy; solid-state NMR

Citation Formats

Edmunds, Charles W., Peralta, Perry, Kelley, Stephen S., Chiang, Vincent L., Sharma-Shivappa, Ratna R., Davis, Mark F., Harman-Ware, Anne E., Sykes, Robert W., Gjersing, Erica, Cunningham, Michael W., Rottmann, William, Miller, Zachary D., and Peszlen, Ilona. Characterization and enzymatic hydrolysis of wood from transgenic Pinus taeda engineered with syringyl lignin or reduced lignin content. United States: N. p., 2017. Web. doi:10.1007/s10570-017-1231-z.
Edmunds, Charles W., Peralta, Perry, Kelley, Stephen S., Chiang, Vincent L., Sharma-Shivappa, Ratna R., Davis, Mark F., Harman-Ware, Anne E., Sykes, Robert W., Gjersing, Erica, Cunningham, Michael W., Rottmann, William, Miller, Zachary D., & Peszlen, Ilona. Characterization and enzymatic hydrolysis of wood from transgenic Pinus taeda engineered with syringyl lignin or reduced lignin content. United States. doi:10.1007/s10570-017-1231-z.
Edmunds, Charles W., Peralta, Perry, Kelley, Stephen S., Chiang, Vincent L., Sharma-Shivappa, Ratna R., Davis, Mark F., Harman-Ware, Anne E., Sykes, Robert W., Gjersing, Erica, Cunningham, Michael W., Rottmann, William, Miller, Zachary D., and Peszlen, Ilona. Wed . "Characterization and enzymatic hydrolysis of wood from transgenic Pinus taeda engineered with syringyl lignin or reduced lignin content". United States. doi:10.1007/s10570-017-1231-z. https://www.osti.gov/servlets/purl/1347200.
@article{osti_1347200,
title = {Characterization and enzymatic hydrolysis of wood from transgenic Pinus taeda engineered with syringyl lignin or reduced lignin content},
author = {Edmunds, Charles W. and Peralta, Perry and Kelley, Stephen S. and Chiang, Vincent L. and Sharma-Shivappa, Ratna R. and Davis, Mark F. and Harman-Ware, Anne E. and Sykes, Robert W. and Gjersing, Erica and Cunningham, Michael W. and Rottmann, William and Miller, Zachary D. and Peszlen, Ilona},
abstractNote = {Softwood is an abundant resource; however, currently its utilization for bioconversion to obtain platform sugars is limited. Pinus taeda trees which were genetically modified to either produce S lignin or to decrease lignin content were characterized with a suite of analytic techniques. Syringyl lignin was visualized in the secondary xylem of one genetic line with Maule staining. Solid-state nuclear magnetic resonance identified the S lignin units were coupled into the lignin through β-O-4 linkages, and thioacidolysis measured approximately 13% S lignin content in the same sample. Reductions of the lignin of as much as 33% were observed in the transgenics. To better understand how these modifications affect bioconversion, their amenability to hot water and dilute acid pretreatments and enzymatic hydrolysis was evaluated. Lignin reductions resulted in 1.9-3.2-fold increases in glucose release compared to the control. However, no apparent benefit was observed by S lignin incorporation at the concentrations reported in this study. Finally, these results highlight the potential for softwood cell wall properties to be improved for bioenergy/biochemical applications.},
doi = {10.1007/s10570-017-1231-z},
journal = {Cellulose},
number = 4,
volume = 24,
place = {United States},
year = {Wed Feb 22 00:00:00 EST 2017},
month = {Wed Feb 22 00:00:00 EST 2017}
}

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