Active toward xylan, carboxymethylcellulose, P-nitrophenyl-beta-D-xylopyranoside and P-nitrophenyl-beta-D-cellobioside. Endohydrolysis of (1->4)-beta-D-glucosidic linkages in cellulose, lichenin and cereal beta-D-glucans. Endohydrolysis of (1->4)-beta-D-xylosidic linkages in xylans. Optimum pH is 7.0. Optimum temperature is 80 degrees Celsius. Glycan degradation; xylan degradation. Belongs to the glycosyl hydrolase 10 (cellulase F) family.