title: Enzymatic bleaching of organosolv sugarcane bagasse pulps with recombinant xylanase of the fungus Humicola grisea and with commercial Cartazyme HS xylanase.
abstract: Organosolv (ethanol/water and acetosolv) pulps were treated with Humicola grisea var. thermoidea and compared with Cartazyme HS xylanase-treated pulp. The ethanol/water pulps treated with H. grisea had the same viscosity as unbleached pulps (8 cP). Ethanol/water pulps treated with Cartazyme had higher viscosity than H. grisea-treated pulps (12 cP). Acetosolv pulps treated with H. grisea and Cartazyme presented a reduction in viscosity; however, the pulps treated with H. grisea had a lower reduction in viscosity than Cartazyme-treated pulps. Ethanol/water pulps treated with H. grisea had a 23% reduction in kappa number in 4 and 8 h of treatment, compared with the unbleached pulps. Cartazyme-treated pulps had a kappa number similar to that of the control pulps for 4 h of treatment. Extending the treatment time to 12 h resulted in a reduction of 33%. The acetosolv pulp treated with H. grisea had a kappa number reduced to 23% in 4 h. Cartazyme treatment resulted in a reduction of 55 and 44% in kappa number for 4 and 8 h of treatment, respectively, when compared with control pulp. Extending the treatment time to 12 h decreased the kappa number 72%. Fourier transform infrared spectra and principal component analysis showed differences among unbleached, H. grisea-treated, and Cartazyme-treated pulps.
authors.affiliation: Departamento de Biotecnologia, FAENQUIL, CP 116, CEP 12600-970, Lorena, SP, Brazil.
authors.forename: Regina Y
authors.initials: RY
authors.lastname: Moriya
authors.forename: Adilson R
authors.initials: AR
authors.lastname: Gonçalves
authors.forename: Fabrícia P
authors.initials: FP
authors.lastname: Faria
mesh_terms: D001203:Ascomycota / Q000201:enzymology* / Q000235:genetics; D001407:Bacillus / Q000201:enzymology*; D001711:Biotransformation; D002482:Cellulose / Q000032:analysis / Q000737:chemistry*; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry* / Q000145:classification / Q000235:genetics; D000431:Ethanol / Q000737:chemistry*; D007220:Industrial Waste / Q000517:prevention & control; D011994:Recombinant Proteins / Q000737:chemistry; D012037:Refuse Disposal / Q000379:methods; D031786:Saccharum / Q000737:chemistry*; D014783:Viscosity; D014867:Water / Q000737:chemistry*
chemical_list: D007220:Industrial Waste; D011994:Recombinant Proteins; D014867:Water; D000431:Ethanol; D002482:Cellulose; C027433:bagasse; D043364:Endo-1,4-beta Xylanases