Commercial cellulase preparations effectively hydrolyze cellulose present in liquid hot water pretreated distillers grains (DG) to glucose.  However, commercial xylanase preparations yield approximately 25% of the xylose and arabinose from the hemicellulose fraction of the same hydrolysate.  Since hemicellulose accounts for nearly 40% of the carbohydrate content of DG, optimizing enzyme activities is required to maximize total fermentable sugar yields from this biomass material.  In this paper we report the effect of supplementing commercial xylanase with additional enzyme activities.  The addition of these enzymes to commercial cellulase significantly increased the yields of arabinose and xylose to 78%.  Also presented is the effect of high solids concentrations on yield and rate of xylose and arabinose liberation.