Biofuels are produced from plant-derived biomass through the breakdown of the plant cell wall, which contains sugars that can be used for energy. A considerable amount of effort has been directed to developing effective enzymes for degrading the cell wall, but the development of more efficient and cost-effective enzymes for biomass-to-biofuel conversion has been limited for several reasons. For one, it is not well understood how enzymes interact with biomass substrates, which have highly complex and heterogeneous physical and chemical properties. Moreover, there is a lack of adequate biomass model substrates for evaluating the efficacy of different enzymes.
To address this problem, researchers from Washington State University, in collaboration with scientists from EMSL, have developed a set of biomass reference substrates with controlled physical and chemical properties which can be used to identify specific deficiencies of cellulase enzymes in breaking down carbohydrate polymers. In a new study, the researchers used these reference substrates to test the effectiveness of three commercially available enzyme mixtures—Novozymes Cellic® Ctec2, Dupont Accellerase® 1500, and DSM Cytolase CL—using X-ray photoelectron spectroscopy, X-ray diffraction and an atomic force microscope at EMSL, the Environmental Molecular Sciences Laboratory, a DOE national scientific user facility.