Influence of pretreatments on enzymic degradation of a cellulose-rich residue from sugar-beet pulp

A cellulose-rich residue (similar to 55% of glucose), obtained by hydrolysis of sugar-beet pulp by a commercial pectinase 'SP 584', was dried, ground and stored. Among 13 commercial enzymic preparations rested for its degradation, six: degraded this material, releasing similar to 8 to similar to 20% of its total neutral sugars. The most efficient were 'Celluclast 1.5L' and 'Cellulase', which released first cellobiose (maximal yield at t = 6-8 h), and Inter degraded down to glucose. Increasing the enzyme concentration led to an increased release of cellobiose and glucose, and a faster degradation of cellobiose into glucose. Yields of cellobiose can be increased from 6.5 to 16% by removing the reaction products. 'Celluclast 1.5L' was shown to act adsorbed on its substrate. Degradation of cellulose by 'Celluclast 1.5L' was influenced by pretreatments, particularly the storage before degradation.