Effect of cellulase loading on digestibilities of pretreated eucalyptus. Materials (1%) treated with ball milling (BM; 120-minute milling), hot-compressed water (HCW; 200°C, 30 minutes) and HCW-BM (160°C, 30 minutes; 40-minute milling) were hydrolyzed for 72 hours with enzyme cocktails consisting of 1-40 FPU Acremonium cellulase, 5 IU Novozyme 188 and 0.02 ml Optimash BG per gram of substrate. The digestibilities were compared on the basis of a cellulase loading of FPU per gram of glucan. The glucan contents in the substrates analyzed with 72% H2SO4 were as follows: HCW (51.9%); BM (40.0%); and HCW-BM (46.6%). The yield of hydrolyzed glucose is expressed as a percentage of the theoretical amount based on the glucan content in the dry weight of untreated biomass.