Cellulose was pre-treated according to a previously reported method. Cellulose (40 mg mL -1 ) and cellulase (2 mg mL -1 ) were added to a 50 mmol L -1 sodium acetate solution titrated to pH = 5 with HCl and stirred at 37 °C. After 24 h, the mixture was heated to 90 °C and stirred for 15 min to denature the enzyme and then filtered. The filtrate was collected (10.6 mg mL -1 glucose; 6.9 mg mL -1 cellobiose) and refrigerated until used.