Enhanced enzymatic hydrolysis of triploid poplar following stepwise acidic pretreatment and alkaline fractionation

► The stepwise processes improve the digestion of the cellulosic substrate. ► Alkaline fractionation dissolved the ubiquitously toxic inhibitors. ► Alkaline treatment isolates hemicelluloses and lignin from pretreated residue. ► This approach is beneficial for the full utilization of lignocellulosic biomass.