<i>Volvariella volvacea</i> Processive Endoglucanase EG1 Treatment Improved the Physical Strength of Bleached Pulps and Reduced Vessel Picking in <i>Eucalyptus</i> Pulp.

Abstract

<i>Volvariella volvacea</i> endoglucanase EG1 was used to treat bleached softwood kraft pulp (BSKP) and hardwood pulp (BHKP) to improve the refinability and physical strength, as well as to reduce vessel picking in <i>Eucalyptus</i> pulp. The results indicated that BSKP was treated with an enzyme dosage of 3 U/g for 2 h at 12,000 refining revolutions, which increased the tensile index from 71.4 N·m/g to 86.7 N·m/g. For BHKP, treatment with 10 U/g of EG1 for 2 h at 15,000 refining revolutions improved the tensile index from the control of 47.7 N·m/g to 56.9 N·m/g. Vessel-removed and vessel-enriched fractions of <i>Eucalyptus</i> pulp were obtained by screening and treated with EG1, respectively. It was found that EG1-assisted refining increased the physical strength and surface strength of both pulp fractions, and the latter improved even more, with increases of 22.4% and 160%, respectively.