Evaluation of selected Ceriporiopsis subvermispora strains for biosulfite pulping and bleaching to prepare dissolving pulp

Five strains of the white-rot fungus Ceriporiopsis subvermispora have been screened for their abilities to facilitate the acid sulfite pulping and bleaching processes of Eucalyptus grandis wood to dissolving pulp. Biosulfite pulp was fully bleached in three bleaching combinations. In most instances a brightness gain over the controls (up to 3 brightness points) was observed. Although the yield of the SS-5-pretreated pulp was lower than the control after biosulfite pulping (by 0.5%), it was higher after bleaching in all three combinations (by up to 1%). Results suggested that pretreatment of wood with selected strains of white-rot fungi may be used as means of improving the selectivity of both pulping and bleaching thereby increasing either the final pulp yield or brightness.