화학공학소재연구정보센터
Biotechnology Letters, Vol.37, No.3, 633-641, 2015
Debranching of soluble wheat arabinoxylan dramatically enhances recalcitrant binding to cellulose
The presence of xylan is a detriment to the enzymatic saccharification of cellulose in lignocelluloses. The inhibition of the processive cellobiohydrolase Cel7A by soluble wheat arabinoxylan is shown here to increase by 50 % following enzymatic treatment with a commercially-purified alpha-l-arabinofuranosidase. The enhanced inhibitory effect was shown by T-2 relaxation time measurements via low field NMR to coincide with an increasing degree of constraint put on the water in xylan solutions. Furthermore, quartz crystal micro-balance with dissipation experiments showed that alpha-l-arabinofuranosidase treatment considerably increased the rate and rigidity of arabinoxylan mass association with cellulose. These data also suggest significant xylan-xylan adlayer formation occurs following initial binding of debranched arabinoxylan. From this, we speculate the inhibitory effects of xylan to cellulases may result from reduced enzymatic access via the dense association of xylan with cellulose.