New Pulp Biobleaching System Involving Manganese Peroxidase Immobilized in a Silica Support with Controlled Pore Sizes

Biobleaching of Bagasse Pulp with Xylanase Enzymes and Hydrogen Peroxide

The effect of the operating conditions (temperature, time, pH, enzyme level and pulp consistency) used in the enzymatic step of a XP (Cartazyme-hydrogen peroxide) sequence for bleaching Kraft pulp from bagasse on various properties of the resulting pulp and paper sheet products was studied. The quality of bagasse used, was examined by its yield, brightness,viscosity and the Kappa number. Finall...

High-temperature post-processing treatment of silica nanofoams of controlled pore sizes and porosities

Manganese Peroxidase, Produced by Trametes versicolor during Pulp Bleaching, Demethylates and Delignifies Kraft Pulp.

Previous work has shown that Trametes (Coriolus) versicolor bleaches kraft pulp brownstock with the concomitant release of methanol. In this work, the fungus is shown to produce both laccase and manganese peroxidase (MnP) but not lignin peroxidase during pulp bleaching. MnP production was enhanced by the presence of pulp and/or Mn(II) ions. The maximum level of secreted MnP was coincident with ...

Delignification of eucalypt kraft pulp with manganese-substituted polyoxometalate assisted by fungal versatile peroxidase.

Oxidation of the manganese-substituted polyoxometalate [SiW(11)Mn(II)(H(2)O)O(39)](6-) (SiW(11)Mn(II)) to [SiW(11)Mn(III)(H(2)O)O(39)](5-) (SiW(11)Mn(III)), one of the most selective polyoxometalates for the kraft pulp delignification, by versatile peroxidase (VP) was studied. First, SiW(11)Mn(II) was demonstrated to be quickly oxidized by VP at room temperature in the presence of H(2)O(2) (K(m...

Biocatalytic activity of Aspergillus niger xylanase in paper pulp biobleaching

Xylanase is a hemicellulase enzyme that catalyses the hydrolysis of xylan to xylose which is widely used in processing of feed, pulp and paper. It is produced by many microorganisms especially filamentous fungi like Trichoderma and Aspergillus. A potential xylanolytic fungal isolate Aspergillus niger was isolated from forest soils of Tirumala, AP, India, and its crude enzyme was checked for its...