Enzymatic hydrolysis of the pretreated solid substrates was
conducted. The substrate enzymatic digestibility (SED), defined
as the percentage of glucan in the substrate converted to glucose,
and the enzymatic hydrolysis glucose yield (EHGY) in kg ton1 untreated
wood were determined. Enzymatic hydrolysis was carried
out at 2% substrate solids (w/v) in 100 mL of sodium acetate buffer
(pH 4.8, concentration 100 mM) on a shaker/incubator (Thermo
Fisher Scientific, Model 4450, Waltham, MA) at 50 C and
200 rpm. Commercial enzymes of Celluclast 1.5 L at 7.5 FPU g1
glucan and Novozyme 188 (b-glucosidase) at 11.25 CBU g1 glucan
were used. This relatively low enzyme dosage was chosen for
detecting differences among the genotypes. Hydrolysate was sampled
periodically for glucose concentration. Each data point is the
average of duplicates. The average relative standard deviation
was about 2%.