Substrate Factors that Influence Cellulase Accessibility and Catalytic Activity During the Enzymatic Hydrolysis of Lignocellulosic Biomass

  • Jinguang HuEmail author
  • Rui Zhai
  • Dong Tian
  • Jack N. Saddler


The development of a renewable, biomass based, “biorefinery” process for fuels and chemicals will be crucial if we are to transit to a more environmentally friendly economy. However, the limited efficacy of the “cellulase mixture” to break down the polysaccharides within lignocellulose into sugar platform is still the bottleneck. Although the catalytic activities of cellulases are comparable with other polysaccharide-degrading enzymes such as amylases, the hydrolytic potential of cellulase enzymes toward pretreated lignocellulosic substrates is much lower. This is primarily due to the limited accessibility of the enzymes to most of the glycosidic bonds and the inhibitory compounds naturally existed and/or derived from biomass deconstruction process.

In this chapter, the major substrate characteristics of pretreated biomass (e.g., gross fiber characters, lignin/hemicellulose content/location, and cellulose allomorph/crystallinity/DP) that influence the accessibility and the hydrolytic performance of cellulase enzymes will be systematically discussed, in combination with various methods that have been used to quantify the changes in the accessibility of lignocellulosic substrate at the macroscopic (fiber), microscopic (fibril), and nanoscopic (microfibril) levels. In addition, the influence of potentially inhibitory biomass-derived soluble compounds on the slowdown of enzymatic hydrolysis, as well as their possible inhibitory mechanisms such as reversible/irreversible inhibition and adsorption/precipitation of the major enzyme activities (exo-/endo-glucanase, β-glucosidase, xylanase activities, etc.), will be elucidated. The possible solutions/strategies to improve cellulose accessibility and to overcome various inhibitors will be also introduced. This chapter will show how overall protein/enzyme loading required to achieve effective cellulose hydrolysis can be significantly reduced by tailoring enzyme mixture for different biomass substrates and the various types of pretreatment used.


Pretreatment Cellulose hydrolysis Enzyme synergism Enzyme inhibition 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Jinguang Hu
    • 1
    Email author
  • Rui Zhai
    • 1
    • 2
  • Dong Tian
    • 1
    • 3
  • Jack N. Saddler
    • 1
  1. 1.Forest Products Biotechnology/Bioenergy Group, Department of Wood Science, Faculty of ForestryThe University of British ColumbiaVancouverCanada
  2. 2.School of Environmental and Biological EngineeringNanjing University of Science and TechnologyNanjingChina
  3. 3.Institute of Ecological and Environmental SciencesSichuan Agricultural UniversityChengduPeople’s Republic of China

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