Impact of xylan on synergistic effects of xylanases and cellulases in enzymatic hydrolysis of lignocelluloses.

Supplementation of xylanase (XYL) has been found to synergistically improve the performance of cellulases (CEL) in the hydrolysis of lignocelluloses. However, the effect of xylan on the synergistic effects of XYL and CEL is still unclear. In this work, the effect of xylan on the synergy between CEL and XYL was investigated. Xylan content in corn stover was generally a good indicator of the degree of the synergism between CEL and XYL. Strongest synergism was observed in the hydrolysis of cellulose in corn stover with the highest xylan contents. A more evident synergistic effect of CEL in xylan hydrolysis was observed in the substrates with low original xylan content. It was also found that the ratio of cellulose to xylan in substrates correlated to the synergism between the two types of enzymes. The results indicated that supplementation of XYL with CEL was most effective in the hydrolysis of corn stover with the highest xylan content. For efficient enzymatic hydrolysis of lignocelluloses, both cellulases and xylanase were important because cellulose and xylan coved each other and these enzymes could improve their performance each other in the hydrolysis of cellulose and xylan in lignocelluloses.