EFFECTS OF CELLULASES AND HEMICELLULASE ON THE ALKALINE SOLUBILITY OFDISSOLVING PULPS

Softwood and hardwood dissolving pulps were treated with purified Tric hoderma reesei endoglucanases, cellobiohydrolases and hemicellulases. Endoglucanase II decreased the viscosity and increased the alkaline so lubility of the pulps most efficiently. The effect of EG II was not cl early improved by the action of hemicellulases or other cellulases. On ly limited removal of the residual hemicelluloses of the pulps could b e obtained using hemicellulases. No synergy was observed between the c ellulases and hemicellulases nor between the different endoglucanases in a combined treatment. As expected, a synergistic effect in the hydr olysis of cellulose was obtained in the combined treatment with endogl ucanases and cellobiohydrolases. However, this was not visualised in e ither the viscosity or the alkaline solubility.