Figure 4.

Endo-and exo-glucanase activity of CEL-HYB1 with and without the CBM. The endo-β-1,4-glucanase (A) and exo-β-1,4-glucanase activity (B) of CEL-HYB1, CEL-HYB1-CBM, and the T. reesei cellulase enzyme cocktail (U mg⁻¹ ± SD) were compared. Measurements shown in (A) were determined using acid-pre-treated Sorghum material as the substrate, whereas measurements shown in (B) were determined using the MUC assay. The measurements were repeated three times. The activity is expressed as μmol of reducing sugar min⁻¹ (U) mg⁻¹ for the Sorghum assay, whereas the result of MUC activity assay is expressed as μmol of MU min⁻¹ (U) mg⁻¹. The endo-β-1,4-glucanase assay was performed at 37°C and pH 6.0 for CEL-HYB1 and CEL-HYB1-CBM, whereas for T. reesei, cellulose enzyme measurement was carried out at 60°C and pH 4.8. The MUC assay was performed at 37°C and pH 6.0 for all enzymes. Values with the same letters are not different significantly at P < 0.05 (Fisher’s LSD test).