2.2.1 Cellulases
Cellulases are produced by molds, bacteria, or single-celled organisms and can hydrolyze cellulose and catalyze the separated links glucoside in the cellulose molecule, with the end product being glucose (Hoa N T, 2014, ). The enzymes (cellulases, hemicellulases, and pectinases) seem to be effective in breaking down the structure of the cotyledon cell wall and lipid body membranes, which leads to disruption of structural integrity, thereby increasing the permeability of the cell wall, finally resulting in enhancement of the extraction yield (Puri, 2012). Several studies on enzyme-assisted extraction of soybean flour have shown promising progress in increasing protein yield (Jung, 2006.) as well as improving the nutritional and sensory properties (Wei, 2018.) of the extracted product by cellulases. A study demonstrated that treatment with cellulase, xylanase, and pectinase alone for a 2-hour alkali extraction resulted in a 13% increase in protein yield compared to a 3-hour alkali extraction. Thus, with the help of the enzymes, not only the alkaline extraction time is reduced but also the protein yield is positively affected. Furthermore, the proteins from the enzyme-assisted alkaline extraction exhibited better solubility, emulsification, and whipping properties (Perović et al., 2020).