Biofuels pp 233-245 | Cite as

Assessing Cellulase Performance on Pretreated Lignocellulosic Biomass Using Saccharification and Fermentation-Based Protocols

  • Nancy Dowe
Part of the Methods in Molecular Biology book series (MIMB, volume 581)


Cellulase enzyme is a key cost component in the production of fuels and chemicals from lignocellulosic biomass. Cellulolytic ability of the enzyme preparation is often measured by activity assays using model substrates such as filter paper. Using lignocellulosic biomass as the substrate to assess enzyme performance has the potential of being more process relevant. We describe two procedures that use washed pretreated cellulosic material to measure the efficacy of cellulase enzymes. First, a saccharification assay that measures glucose yield as a function of the amount of cellulase used in the process. And second, the simultaneous saccharification and fermentation (SSF) assay measures cellulase performance by the amount of ethanol produced from enzymatic hydrolysis of the cellulosic material. You can use both assays to screen cellulases under a variety of substrate types, loadings, and process conditions.

Key words

Cellulases Lignocellulose Saccharification Simultaneous saccharification and fermentation Pretreatment Biomass Ethanol 



This work was supported by the Office of Biomass Program in the Department of Energy’s Office of Energy Efficiency and Renewable Energy. I would also like to thank my NREL colleagues Daniel Schell, Ali Mohagheghi, Mildred Zuccarello, and Gary McMillen for reviewing this chapter.


  1. 1.
    Hahn-Hägerdal, B., Galbe, M., Gorwa-Grauslund, M.F., Lidén, G., and Zacchi, G. (2006) Bio-ethanol the fuel of tomorrow from the residues of today. Trends Biotechnol. 24, 549–556CrossRefGoogle Scholar
  2. 2.
    Sanchez, O.J., and Cardona, C.A. (2007) Trends in biotechnological production of fuel ethanol from different feedstocks. Bioresour. Technol. 99, 5270–5295CrossRefGoogle Scholar
  3. 3.
    Mielenz, J.R. (2001) Ethanol production from biomass: technology and commercialization status. Curr. Opin. Microbiol. 4, 324–329CrossRefGoogle Scholar
  4. 4.
    Öhgren, K., Bengtsson, O., Gorwa-Grauslund, M.F., Galbe, M., Hahn-Hägerdal, B., and Zacchi, G. (2006) Simultaneous saccharification and co-fermentation of glucose and xylose in steam-pretreated corn stover at high fiber content with Saccharomyces cerevisiae TMB3400. J. Biotechnol. 126, 488–498CrossRefGoogle Scholar
  5. 5.
    Toon, S.T., Philippidis, G.P., Ho, N.W.Y, Brainard, A., Lumpkin, R.E., and Riley, C.J. (1997) Enhanced cofermentation of glucose and xylose by recombinant Saccharomyces yeast strains in batch and continuous operating modes. Appl. Biochem. Biotechnol. 63–65, 243–268CrossRefGoogle Scholar
  6. 6.
    Aden, A., Ruth, M., Ibsen, K., Jechura, J., Neeves, K., Sheehan, J., Wallace, B., Montague, L., Slayton, A., and Lukas, J. (2002) Lignocellulosic biomass to ethanol process design and economics utilizing co-current dilute acid prehydrolysis and enzymatic hydrolysis for corn stover. National Renewable Energy Laboratory Technical Report NREL/TP-510–32438 (
  7. 7.
    Wooley, R., Ruth, M., Glassner, D., and Sheehan, J. (1999) Process design and costing of bioethanol technology: a tool for determining the status and direction of research and development. Biotechnol. Prog. 15, 794–803CrossRefGoogle Scholar
  8. 8.
    Haki, G.D. and Rakshit, S.K. (2003) Developments in industrially important thermostable enzymes: a review. Bioresour. Technol. 89, 17–34CrossRefGoogle Scholar
  9. 9.
    Zhang, Y.H.P., Himmel, M.E., and Mielenz, J.R. (2006) Outlook for cellulase improvement: screening and selection strategies. Biotechnol. Adv. 24, 452—481CrossRefGoogle Scholar
  10. 10.
    Ghose, T.K. (1987) Measurement of cellulase activities. Pure Appl. Chem. 59, 257–268CrossRefGoogle Scholar
  11. 11.
    Szakács, G., Urbánszki, K., and Tengerdy, R.P. (2001) Solid-state enzymes for fiber hydrolysis. In: Himmel, M.E., Baker, J.O., and Saddler, J.N. (eds.) Glycosyl Hydrolases for Biomass Conversion. American Chemical Society: Washington, D.C., pp. 190–203Google Scholar
  12. 12.
    McMillan, J.D., Dowe, N., Mohagheghi, A., and Newman, M.M. (2001) Assessing the efficacy of cellulase enzyme preparations under simultaneous saccharification fermentation processing conditions. In: Himmel, M.E., Baker, J.O., and Saddler, J.N. (eds.) Glycosyl Hydrolases for Biomass Conversion. American Chemical Society: Washington, D.C., pp. 144–166Google Scholar
  13. 13.
    Grohmann, K. (1993) Simultaneous saccharification and fermentation of cellulosic substrates to ethanol. In: Saddler, J.N. (ed.) Bioconversion of Forest and Agricultural Plant Residues. CAB International: Wallingford, Oxon, UK, pp. 183–209Google Scholar
  14. 14.
    Walker, G.M. (1998) Yeast Physiology and Biotechnology. Wiley: Chichester, West Sussex, EnglandGoogle Scholar
  15. 15.
    Difco Laboratories (1984) Difco Manual 10th Edition. Difco Laboratories: Detroit, MIGoogle Scholar

Copyright information

© Humana Press, a part of Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Nancy Dowe
    • 1
  1. 1.National Renewable Energy LaboratoryGoldenUSA

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