tThe sono-assisted alkaline pretreatment of sugarcane bagasse was optimized using a central compositedesign in which the glucose recovery after enzymatic hydrolysis was used as the response function.Cellic®CTec3 (Novozymes) and Thermossac®Dry (Lallemand) were used for enzymatic hydrolysis andfermentation, respectively. The best performance was achieved at 70◦C with 140 W of sonication powerusing 0.125 g of NaOH g−1of dry biomass, yielding a total glucose recovery of 95.8 wt% in relation to thetotal glucan content of the original material. The fermentation efficiency of the best substrate hydrolysatewas 91.4%, whereas lower values of 87.1 and 80.0% were obtained for steam-exploded and sono-assistedalkali-washed steam-exploded cane bagasse, respectively. In addition, when the glucan recovery of eachpretreatment method was taken into account, the total C6 cellulosic ethanol production from the sono-assisted alkali-washed cane bagasse was 20.4 and 40.6% higher than that of the other two pretreatmenttechnologies, respectively