Xylanase and β-Xylosidase from Penicillium janczewskii: Production, Physico-Chemical properties, and application of the crude extract to pulp biobleaching
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Data
2013-02-01
Autores
Terrasan, César R. F.
Temer, Beatriz [UNESP]
Sarto, Camila
Silva Júnior, Francides G.
Carmona, Eleonora C. [UNESP]
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Resumo
Extracellular xylanase and β-xylosidase production by a Penicillium janczewskii strain were investigated in liquid cultures with xylan from oat spelts under different physical and chemical conditions. The selected conditions for optimized production of xylanase and β-xylosidase were 7 days, pH 6.5, at 30 °C and 8 days, pH 5.0, at 25 °C, respectively. The xylanase exhibited optimal activity in pH 5.0 at 50 °C and the β- xylosidase in pH 4.0 at 75 °C. The xylanase was more stable at pH 6.0 to 9.5, while the β-xylosidase remained stable at pH ranging from 1.6 to 5.5. The xylanase half-life (T50) at 40, 50, and 60 °C was 183, 15, and 3 min, respectively. β-xylosidase half-life was 144, 8, and 4 min at 50, 65, and 75 °C, respectively. When applied to the biobleaching of Eucalyptus kraft pulp, xylanase dosages of 2 and 4 U/g dried pulp reduced, respectively, kappa number by 3.0 and 3.3 units after 1 h treatment, demonstrating that the use of P. janczewskii xylanases in this process is quite promising. The pulp viscosity was not altered, confirming the absence of cellulolytic enzymes in the fungal extract.
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Enzyme characterization, Enzyme production, Penicillium janczewskii, Pulp biobleaching, Xylanolytic enzymes, Biobleaching, Bast fibers, Chemical properties, Kraft pulp, Optimization, Enzyme activity, Chemical Properties, Enzymes, Fibers, Kraft Pulps, Phloem
Como citar
BioResources, v. 8, n. 1, p. 1292-1305, 2013.