To determine the b-glucosidase activity, the method described by Afolabi (1997) utilized a substrate solution containing 1 mg/
mL of pNPG (p-Nitrophenyl b-D-glucopyranoside) in 0.2 M acetate buffer, pH 5.2. A volume of 0.1 mL of crude enzymatic extract was added to 1.9 mL of substrate and incubated for 30 min at 50 C. Subsequently, 0.5 mL of a 2% sodium carbonate was added and quantification performed in a spectrophotometer at 405 nm.