Cellulase can break down cellulose, and the final product is glucose.

Cellulase is a complex enzyme system composed of a variety of hydrolases. Many fungi in nature can secrete cellulase. Conventionally, cellulases are divided into three categories: C1 enzyme, Cx enzyme and β-glucosidase. The C1 enzyme is the enzyme that initially acts on cellulose, destroying the crystalline structure of the cellulose chains. Cx enzyme is a cellulase that acts on cellulose activated by C1 enzyme and decomposes β-1,4-glucosidic bonds. Beta glucosidase can break down cellobiose, cellotriose and other low molecular weight cellodextrins into glucose.