Cellulase enzymes constitute a complex of glycoside hydrolases that are secreted by microorganisms, plants and some animals. These enzymes act on the hydrolysis of β-1,4–glucosidic bonds of the cellulose structure, the major polymer present on biomass. Recent attention has been given on cellulases use in the bioconversion process of lignocellulosic materials into bioethanol and biobased products, within the biorefinery concept. Besides that, cellulases have been largely applied at different industrial areas like textile, food, brewery and wine, animal feed, pulp and paper industries. This chapter will describe some current state of knowledge related to cellulase assays using soluble and insoluble substrates, focusing on the need to standardized methods in order to allow a comparison among different enzyme preparations.
Keywords: Enzyme, cellulase, polysaccharides, enzyme assays, activity, endoglucanase, β-glucosidases, exoglucanases, enzyme action, hydrolysis, DNS, glucose, cellobiose, cellulose, Trichoderma reesei, Aspergillus niger, biofuels, bioconversion, reducing sugar, glycosidic bond.