Xylanase contribution to the efficiency of cellulose enzymatic hydrolysis of barley straw

In this study, different enzyme preparations available from Novozymes were assessed for their efficiency to hydrolyze lignocellulosic materials. The enzyme mixture was evaluated on a pretreated cellulose-rich material, and steam-exploded barley straw pretreated under different temperatures (190, 200, and 210°C, respectively) in order to produce fermentable sugars. Results show that xylanase supplementation improves initial cellulose hydrolysis effectiveness of water-insoluble solid fraction from all steam-exploded barley straw samples, regardless of the xylan content of substrate. The mixture constituted by cellulase: β-glucosidase: endoxylanase of the new kit for lignocellulose conversion at a ratio 10:1:5% ([v/w], enzyme [E]/substrate [S]) provides the highest increment of cellulose conversion in barley straw pretreated at 210°C, for 10 min.