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Title: Biological lignocellulose solubilization: Comparative evaluation of biocatalysts and enhancement via cotreatment

Abstract

Here, feedstock recalcitrance is the most important barrier impeding cost-effective production of cellulosic biofuels. Pioneer commercial cellulosic ethanol facilities employ thermochemical pretreatment and addition of fungal cellulase, reflecting the main research emphasis in the field. However, it has been suggested that it may be possible to process cellulosic biomass without thermochemical pretreatment using thermophilic, cellulolytic bacteria. To further explore this idea, we examine the ability of various biocatalysts to solubilize autoclaved but otherwise unpretreated cellulosic biomass under controlled but not industrial conditions. As a result, carbohydrate solubilization of mid-season harvested switchgrass after 5 days ranged from 24 % for Caldicellulosiruptor bescii to 65 % for Clostridium thermocellum, with intermediate values for a thermophilic horse manure enrichment, Clostridium clariflavum, Clostridium cellulolyticum, and simultaneous saccharification and fermentation (SSF) featuring a fungal cellulase cocktail and yeast. Under a variety of conditions, solubilization yields were about twice as high for C. thermocellum compared to fungal cellulase. Solubilization of mid-season harvested switchgrass was about twice that of senescent switchgrass. Lower yields and greater dependence on particle size were observed for Populus as compared to switchgrass. Trends observed from data drawn from six conversion systems and three substrates, including both time course and end-point data, weremore » (1) equal fractional solubilization of glucan and xylan, (2) no biological solubilization of the non-carbohydrate fraction of biomass, and (3) higher solubilization for three of the four bacterial cultures tested as compared to the fungal cellulase system. Brief (5 min) ball milling of solids remaining after fermentation of senescent switchgrass by C. thermocellum nearly doubled carbohydrate solubilization upon reinnoculation as compared to a control without milling. Greater particle size reduction and solubilization were observed for milling of partially fermented solids than for unfermented solids. Physical disruption of cellulosic feedstocks after initiation of fermentation, termed cotreatment, warrants further study. While the ability to achieve significant solubilization of minimally pretreated switchgrass is widespread, a fivefold difference between the most and least effective biocatalyst-feedstock combinations was observed. Starting with nature's best biomass-solubilizing systems may enable a reduction in the amount of non-biological processing required, and in particular substitution of cotreatment for pretreatment.« less

Authors:
 [1];  [1];  [1];  [2];  [2];  [3];  [2];  [2];  [4];  [4];  [5];  [5];  [1]
  1. Dartmouth College, Hanover, NH (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); National Renewable Energy Lab. (NREL), Golden, CO (United States)
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of California, Riverside, CA (United States)
  5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Georgia, Athens, GA (United States)
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1236762
Alternate Identifier(s):
OSTI ID: 1327645
Report Number(s):
NREL/JA-5100-65764
Journal ID: ISSN 1754-6834
Grant/Contract Number:  
AC36-08GO28308; AC05-00OR22725
Resource Type:
Accepted Manuscript
Journal Name:
Biotechnology for Biofuels
Additional Journal Information:
Journal Volume: 9; Journal Issue: 1; Related Information: Biotechnology for Biofuels; Journal ID: ISSN 1754-6834
Publisher:
BioMed Central
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; 59 BASIC BIOLOGICAL SCIENCES; biological solubilization; lignocellulose; cotreatment

Citation Formats

Paye, Julie M. D., Guseva, Anna, Hammer, Sarah K., Gjersing, Erica, Davis, Mark F., Davison, Brian H., Olstad, Jessica, Donohoe, Bryon S., Nguyen, Thanh Yen, Wyman, Charles E., Pattathil, Sivakumar, Hahn, Michael G., and Lynd, Lee R. Biological lignocellulose solubilization: Comparative evaluation of biocatalysts and enhancement via cotreatment. United States: N. p., 2016. Web. doi:10.1186/s13068-015-0412-y.
Paye, Julie M. D., Guseva, Anna, Hammer, Sarah K., Gjersing, Erica, Davis, Mark F., Davison, Brian H., Olstad, Jessica, Donohoe, Bryon S., Nguyen, Thanh Yen, Wyman, Charles E., Pattathil, Sivakumar, Hahn, Michael G., & Lynd, Lee R. Biological lignocellulose solubilization: Comparative evaluation of biocatalysts and enhancement via cotreatment. United States. doi:10.1186/s13068-015-0412-y.
Paye, Julie M. D., Guseva, Anna, Hammer, Sarah K., Gjersing, Erica, Davis, Mark F., Davison, Brian H., Olstad, Jessica, Donohoe, Bryon S., Nguyen, Thanh Yen, Wyman, Charles E., Pattathil, Sivakumar, Hahn, Michael G., and Lynd, Lee R. Tue . "Biological lignocellulose solubilization: Comparative evaluation of biocatalysts and enhancement via cotreatment". United States. doi:10.1186/s13068-015-0412-y. https://www.osti.gov/servlets/purl/1236762.
@article{osti_1236762,
title = {Biological lignocellulose solubilization: Comparative evaluation of biocatalysts and enhancement via cotreatment},
author = {Paye, Julie M. D. and Guseva, Anna and Hammer, Sarah K. and Gjersing, Erica and Davis, Mark F. and Davison, Brian H. and Olstad, Jessica and Donohoe, Bryon S. and Nguyen, Thanh Yen and Wyman, Charles E. and Pattathil, Sivakumar and Hahn, Michael G. and Lynd, Lee R.},
abstractNote = {Here, feedstock recalcitrance is the most important barrier impeding cost-effective production of cellulosic biofuels. Pioneer commercial cellulosic ethanol facilities employ thermochemical pretreatment and addition of fungal cellulase, reflecting the main research emphasis in the field. However, it has been suggested that it may be possible to process cellulosic biomass without thermochemical pretreatment using thermophilic, cellulolytic bacteria. To further explore this idea, we examine the ability of various biocatalysts to solubilize autoclaved but otherwise unpretreated cellulosic biomass under controlled but not industrial conditions. As a result, carbohydrate solubilization of mid-season harvested switchgrass after 5 days ranged from 24 % for Caldicellulosiruptor bescii to 65 % for Clostridium thermocellum, with intermediate values for a thermophilic horse manure enrichment, Clostridium clariflavum, Clostridium cellulolyticum, and simultaneous saccharification and fermentation (SSF) featuring a fungal cellulase cocktail and yeast. Under a variety of conditions, solubilization yields were about twice as high for C. thermocellum compared to fungal cellulase. Solubilization of mid-season harvested switchgrass was about twice that of senescent switchgrass. Lower yields and greater dependence on particle size were observed for Populus as compared to switchgrass. Trends observed from data drawn from six conversion systems and three substrates, including both time course and end-point data, were (1) equal fractional solubilization of glucan and xylan, (2) no biological solubilization of the non-carbohydrate fraction of biomass, and (3) higher solubilization for three of the four bacterial cultures tested as compared to the fungal cellulase system. Brief (5 min) ball milling of solids remaining after fermentation of senescent switchgrass by C. thermocellum nearly doubled carbohydrate solubilization upon reinnoculation as compared to a control without milling. Greater particle size reduction and solubilization were observed for milling of partially fermented solids than for unfermented solids. Physical disruption of cellulosic feedstocks after initiation of fermentation, termed cotreatment, warrants further study. While the ability to achieve significant solubilization of minimally pretreated switchgrass is widespread, a fivefold difference between the most and least effective biocatalyst-feedstock combinations was observed. Starting with nature's best biomass-solubilizing systems may enable a reduction in the amount of non-biological processing required, and in particular substitution of cotreatment for pretreatment.},
doi = {10.1186/s13068-015-0412-y},
journal = {Biotechnology for Biofuels},
number = 1,
volume = 9,
place = {United States},
year = {2016},
month = {1}
}

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Cited by: 26 works
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Figures / Tables:

Fig. 1 Fig. 1: Solubilization of washed mid-season switchgrass by various biocatalysts. Xylan (white) and glucan (black) solubilization from washed mid-season switchgrass by various bacteria or SSF with yeast and fungal cellulase after 5 days. Enrichment was selected at 60 °C on Avicel from horse manure compost. Uninoculated controls (75, 60, 37more » and 35 °C) for each incubation temperature were analyzed to account for non-biological solubilization. Results are expressed as mean ± SD ($n$ ≥ 2)« less

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Works referenced in this record:

Integrated analysis of hydrothermal flow through pretreatment
journal, January 2012

  • Archambault-Leger, Veronique; Shao, Xiongjun; Lynd, Lee R.
  • Biotechnology for Biofuels, Vol. 5, Issue 1
  • DOI: 10.1186/1754-6834-5-49

Fungal cellulases and complexed cellulosomal enzymes exhibit synergistic mechanisms in cellulose deconstruction
journal, January 2013

  • Resch, Michael G.; Donohoe, Bryon S.; Baker, John O.
  • Energy & Environmental Science, Vol. 6, Issue 6
  • DOI: 10.1039/c3ee00019b

Lessons from the cow: What the ruminant animal can teach us about consolidated bioprocessing of cellulosic biomass
journal, November 2009


Degradation of microcrystalline cellulose and non-pretreated plant biomass by a cell-free extracellular cellulase/hemicellulase system from the extreme thermophilic bacterium Caldicellulosiruptor bescii
journal, January 2013

  • Kanafusa-Shinkai, Sumiyo; Wakayama, Jun'ichi; Tsukamoto, Kazumi
  • Journal of Bioscience and Bioengineering, Vol. 115, Issue 1
  • DOI: 10.1016/j.jbiosc.2012.07.019

Application of monoclonal antibodies to investigate plant cell wall deconstruction for biofuels production
journal, January 2011

  • DeMartini, Jaclyn D.; Pattathil, Sivakumar; Avci, Utku
  • Energy & Environmental Science, Vol. 4, Issue 10
  • DOI: 10.1039/c1ee02112e

Partial acid hydrolysis of cellulosic materials as a pretreatment for enzymatic hydrolysis
journal, July 1980

  • Knappert, Diane; Grethlein, Hans; Converse, Alvin
  • Biotechnology and Bioengineering, Vol. 22, Issue 7, p. 1449-1463
  • DOI: 10.1002/bit.260220711

Enhancement of cellulose accessibility and enzymatic hydrolysis by simultaneous wet milling
journal, May 1980

  • Kelsey, Rick G.; Shafizadeh, Fred
  • Biotechnology and Bioengineering, Vol. 22, Issue 5
  • DOI: 10.1002/bit.260220511

Winter rye as a bioenergy feedstock: impact of crop maturity on composition, biological solubilization and potential revenue
journal, January 2015


Enhancement of enzymatic hydrolysis by simultaneous attrition of cellulosic substrates
journal, February 1982

  • Neilson, Martin J.; Kelsey, Rick G.; Shafizadeh, Fred
  • Biotechnology and Bioengineering, Vol. 24, Issue 2
  • DOI: 10.1002/bit.260240204

Quantitative Saccharification of Wood and Cellulose
journal, January 1945

  • Saeman, Jerome F.; Bubl, Janet L.; Harris, Elwin E.
  • Industrial & Engineering Chemistry Analytical Edition, Vol. 17, Issue 1, p. 35-37
  • DOI: 10.1021/i560137a008

Cellulose fermentation by Clostridium thermocellum and a mixed consortium in an automated repetitive batch reactor
journal, March 2014


Evaluation of the bioconversion of genetically modified switchgrass using simultaneous saccharification and fermentation and a consolidated bioprocessing approach
journal, January 2012

  • Yee, Kelsey L.; Rodriguez Jr, Miguel; Tschaplinski, Timothy J.
  • Biotechnology for Biofuels, Vol. 5, Issue 1
  • DOI: 10.1186/1754-6834-5-81

Dry fractionation process as an important step in current and future lignocellulose biorefineries: A review
journal, April 2013


Development of a low-cost fermentation medium for ethanol production from biomass
journal, June 1997

  • Kadam, K. L.; Newman, M. M.
  • Applied Microbiology and Biotechnology, Vol. 47, Issue 6
  • DOI: 10.1007/s002530050985

Carbohydrate and lignin are simultaneously solubilized from unpretreated switchgrass by microbial action at high temperature
journal, January 2013

  • Kataeva, Irina; Foston, Marcus B.; Yang, Sung-Jae
  • Energy & Environmental Science, Vol. 6, Issue 7
  • DOI: 10.1039/c3ee40932e

Thermophilic lignocellulose deconstruction
journal, May 2014

  • Blumer-Schuette, Sara E.; Brown, Steven D.; Sander, Kyle B.
  • FEMS Microbiology Reviews, Vol. 38, Issue 3
  • DOI: 10.1111/1574-6976.12044

Enhancing the Enzymatic Hydrolysis of Cellulosic Materials Using Simultaneous Ball Milling
journal, January 2002

  • Mais, Ursula; Esteghlalian, Ali R.; Saddler, John N.
  • Applied Biochemistry and Biotechnology, Vol. 98-100, Issue 1-9
  • DOI: 10.1385/ABAB:98-100:1-9:815

Bioconversion of waste cellulose by using an attrition bioreactor
journal, January 1983


Comparative data on effects of leading pretreatments and enzyme loadings and formulations on sugar yields from different switchgrass sources
journal, December 2011


Simultaneous wet ball milling and mild acid hydrolysis of rice hull
journal, January 2010

  • Zhou, Jinxiang; Chen, Ding; Zhu, Yonghua
  • Journal of Chemical Technology & Biotechnology, Vol. 85, Issue 1
  • DOI: 10.1002/jctb.2270

Efficient Degradation of Lignocellulosic Plant Biomass, without Pretreatment, by the Thermophilic Anaerobe "Anaerocellum thermophilum" DSM 6725
journal, May 2009

  • Yang, Sung-Jae; Kataeva, Irina; Hamilton-Brehm, Scott D.
  • Applied and Environmental Microbiology, Vol. 75, Issue 14, p. 4762-4769
  • DOI: 10.1128/AEM.00236-09

Comparative material balances around pretreatment technologies for the conversion of switchgrass to soluble sugars
journal, December 2011


An in vitro Technique for Estimating Digestibility of Treated and Untreated Wood
journal, June 1970

  • Mellenberger, R. W.; Satter, L. D.; Millett, M. A.
  • Journal of Animal Science, Vol. 30, Issue 6
  • DOI: 10.2527/jas1970.3061005x

Combined pretreatment using alkaline hydrothermal and ball milling to enhance enzymatic hydrolysis of oil palm mesocarp fiber
journal, October 2014


Nutritive Value of Corn Silage as Affected by Maturity and Mechanical Processing: A Contemporary Review
journal, December 1999


Microbial Cellulose Utilization: Fundamentals and Biotechnology
journal, September 2002

  • Lynd, L. R.; Weimer, P. J.; van Zyl, W. H.
  • Microbiology and Molecular Biology Reviews, Vol. 66, Issue 3, p. 506-577
  • DOI: 10.1128/MMBR.66.3.506-577.2002

Summary of findings from the Biomass Refining Consortium for Applied Fundamentals and Innovation (CAFI): corn stover pretreatment
journal, June 2009


Enzyme-microbe synergy during cellulose hydrolysis by Clostridium thermocellum
journal, October 2006

  • Lu, Y.; Zhang, Y. -H. P.; Lynd, L. R.
  • Proceedings of the National Academy of Sciences, Vol. 103, Issue 44
  • DOI: 10.1073/pnas.0605381103

Development of switchgrass (Panicum virgatum) as a bioenergy feedstock in the United States
journal, June 2005


Methods for Pretreatment of Lignocellulosic Biomass for Efficient Hydrolysis and Biofuel Production
journal, April 2009

  • Kumar, Parveen; Barrett, Diane M.; Delwiche, Michael J.
  • Industrial & Engineering Chemistry Research, Vol. 48, Issue 8, p. 3713-3729
  • DOI: 10.1021/ie801542g

Continuous attrition bioreactor with enzyme recycling for the bioconversion of cellulose
journal, August 1988

  • Lee, J. M.; Wolf, J. H.
  • Applied Biochemistry and Biotechnology, Vol. 18, Issue 1
  • DOI: 10.1007/BF02930826

Carbon-13 NMR and order in cellulose
journal, March 1982

  • Maciel, Gary E.; Kolodziejski, Waclaw L.; Bertran, Maria S.
  • Macromolecules, Vol. 15, Issue 2
  • DOI: 10.1021/ma00230a097

Effect of rumination on reduction of particle size of rumen digesta by cattle
journal, January 1985

  • Kennedy, Pm
  • Australian Journal of Agricultural Research, Vol. 36, Issue 6
  • DOI: 10.1071/AR9850819

Genome sequencing and analysis of the biomass-degrading fungus Trichoderma reesei (syn. Hypocrea jecorina)
journal, May 2008

  • Martinez, Diego; Berka, Randy M.; Henrissat, Bernard
  • Nature Biotechnology, Vol. 26, Issue 5
  • DOI: 10.1038/nbt1403

Growth inhibition of Clostridium cellulolyticum by an inefficiently regulated carbon flow
journal, August 1999


Comparative sugar recovery and fermentation data following pretreatment of poplar wood by leading technologies
journal, March 2009

  • Wyman, Charles E.; Dale, Bruce E.; Elander, Richard T.
  • Biotechnology Progress, Vol. 25, Issue 2
  • DOI: 10.1002/btpr.142

Hydrolysis of dilute acid pretreated mixed hardwood and purified microcrystalline cellulose by cell-free broth fromClostridium thermocellum
journal, January 1987

  • Lynd, L. R.; Grethlein, H. E.
  • Biotechnology and Bioengineering, Vol. 29, Issue 1
  • DOI: 10.1002/bit.260290114

A defined growth medium with very low background carbon for culturing Clostridium thermocellum
journal, February 2012

  • Holwerda, Evert K.; Hirst, Kyle D.; Lynd, Lee R.
  • Journal of Industrial Microbiology & Biotechnology, Vol. 39, Issue 6
  • DOI: 10.1007/s10295-012-1091-3

Comparative analysis of the ability of Clostridium clariflavum strains and Clostridium thermocellumto utilize hemicellulose and unpretreated plant material
journal, November 2014

  • Izquierdo, Javier A.; Pattathil, Sivakumar; Guseva, Anna
  • Biotechnology for Biofuels, Vol. 7, Issue 1
  • DOI: 10.1186/s13068-014-0136-4

Comparison of Extracellular Cellulase Activities of Clostridium thermocellum LQRI and Trichoderma reesei QM9414
journal, January 1981


Saccharification of Complex Cellulosic Substrates by the Cellulase System from Clostridium thermocellum
journal, January 1982


Enzymatic Hydrolysis of Cellulose
journal, January 1956


    Works referencing / citing this record:

    Harnessing yeast organelles for metabolic engineering
    journal, July 2017

    • Hammer, Sarah K.; Avalos, José L.
    • Nature Chemical Biology, Vol. 13, Issue 8
    • DOI: 10.1038/nchembio.2429

    Nanomechanics of cellulose deformation reveal molecular defects that facilitate natural deconstruction
    journal, April 2019

    • Ciesielski, Peter N.; Wagner, Ryan; Bharadwaj, Vivek S.
    • Proceedings of the National Academy of Sciences
    • DOI: 10.1073/pnas.1900161116

    Bioavailability of Carbohydrate Content in Natural and Transgenic Switchgrasses for the Extreme Thermophile Caldicellulosiruptor bescii
    journal, June 2017

    • Zurawski, Jeffrey V.; Khatibi, Piyum A.; Akinosho, Hannah O.
    • Applied and Environmental Microbiology, Vol. 83, Issue 17
    • DOI: 10.1128/aem.00969-17

    Thermoanaerobacter species differ in their potential to reduce organic acids to their corresponding alcohols
    journal, July 2018

    • Hitschler, Lisa; Kuntz, Michelle; Langschied, Felix
    • Applied Microbiology and Biotechnology, Vol. 102, Issue 19
    • DOI: 10.1007/s00253-018-9210-3

    Global Distribution Patterns and Pangenomic Diversity of the Candidate Phylum “Latescibacteria” (WS3)
    journal, March 2017

    • Farag, Ibrahim F.; Youssef, Noha H.; Elshahed, Mostafa S.
    • Applied and Environmental Microbiology, Vol. 83, Issue 10
    • DOI: 10.1128/aem.00521-17

    Efficient whole-cell-catalyzing cellulose saccharification using engineered Clostridium thermocellum
    journal, May 2017


    Lignocellulose solubilization and conversion by extremely thermophilic Caldicellulosiruptor bescii improves by maintaining metabolic activity
    journal, May 2019

    • Straub, Christopher T.; Khatibi, Piyum A.; Otten, Jonathan K.
    • Biotechnology and Bioengineering, Vol. 116, Issue 8
    • DOI: 10.1002/bit.26993

    Metabolic and evolutionary responses of Clostridium thermocellum to genetic interventions aimed at improving ethanol production
    journal, March 2020

    • Holwerda, Evert K.; Olson, Daniel G.; Ruppertsberger, Natalie M.
    • Biotechnology for Biofuels, Vol. 13, Issue 1
    • DOI: 10.1186/s13068-020-01680-5

    Cellulosomes localise on the surface of membrane vesicles from the cellulolytic bacterium Clostridium thermocellum
    journal, June 2019

    • Ichikawa, Shunsuke; Ogawa, Satoru; Nishida, Ayami
    • FEMS Microbiology Letters, Vol. 366, Issue 12
    • DOI: 10.1093/femsle/fnz145

    Lignocellulosic biomass: Hurdles and challenges in its valorization
    journal, November 2019

    • Singhvi, Mamata S.; Gokhale, Digambar V.
    • Applied Microbiology and Biotechnology, Vol. 103, Issue 23-24
    • DOI: 10.1007/s00253-019-10212-7

    Metabolome analysis reveals a role for glyceraldehyde 3-phosphate dehydrogenase in the inhibition of C. thermocellum by ethanol
    journal, November 2017

    • Tian, Liang; Perot, Skyler J.; Stevenson, David
    • Biotechnology for Biofuels, Vol. 10, Issue 1
    • DOI: 10.1186/s13068-017-0961-3

    Structural features influential to enzymatic hydrolysis of cellulose-solvent-based pretreated pinewood and elmwood for ethanol production
    journal, November 2017

    • Satari, Behzad; Karimi, Keikhosro; Molaverdi, Maryam
    • Bioprocess and Biosystems Engineering, Vol. 41, Issue 2
    • DOI: 10.1007/s00449-017-1863-2

    Engineering a highly active thermophilic β-glucosidase to enhance its pH stability and saccharification performance
    journal, July 2016


    Cellulosic ethanol production via consolidated bioprocessing by a novel thermophilic anaerobic bacterium isolated from a Himalayan hot spring
    journal, March 2017

    • Singh, Nisha; Mathur, Anshu S.; Tuli, Deepak K.
    • Biotechnology for Biofuels, Vol. 10, Issue 1
    • DOI: 10.1186/s13068-017-0756-6

    Enhanced depolymerization and utilization of raw lignocellulosic material by co-cultures of Ruminiclostridium thermocellum with hemicellulose-utilizing partners
    journal, April 2019

    • Froese, Alan; Schellenberg, John; Sparling, Richard
    • Canadian Journal of Microbiology, Vol. 65, Issue 4
    • DOI: 10.1139/cjm-2018-0535

    Engineering a highly active thermophilic β-glucosidase to enhance its pH stability and saccharification performance
    journal, July 2016


    Multiple levers for overcoming the recalcitrance of lignocellulosic biomass
    journal, January 2019

    • Holwerda, Evert K.; Worthen, Robert S.; Kothari, Ninad
    • Biotechnology for Biofuels, Vol. 12, Issue 1
    • DOI: 10.1186/s13068-019-1353-7

    Strain and bioprocess improvement of a thermophilic anaerobe for the production of ethanol from wood
    journal, June 2016

    • Herring, Christopher D.; Kenealy, William R.; Joe Shaw, A.
    • Biotechnology for Biofuels, Vol. 9, Issue 1
    • DOI: 10.1186/s13068-016-0536-8

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