Production of xylanase by Aspergilli using alternative carbon sources: application of the crude extract on cellulose pulp biobleaching
- 15 October 2008
- journal article
- research article
- Published by Oxford University Press (OUP) in Journal of Industrial Microbiology & Biotechnology
- Vol. 36 (1), 149-155
- https://doi.org/10.1007/s10295-008-0482-y
Abstract
The ability of xylanolytic enzymes produced by Aspergillus fumigatus RP04 and Aspergillus niveus RP05 to promote the biobleaching of cellulose pulp was investigated. Both fungi grew for 4–5 days in liquid medium at 40°C, under static conditions. Xylanase production was tested using different carbon sources, including some types of xylans. A. fumigatus produced high levels of xylanase on agricultural residues (corncob or wheat bran), whereas A. niveus produced more xylanase on birchwood xylan. The optimum temperature of the xylanases from A. fumigatus and A. niveus was around 60–70°C. The enzymes were stable for 30 min at 60°C, maintaining 95–98% of the initial activity. After 1 h at this temperature, the xylanase from A. niveus still retained 85% of initial activity, while the xylanase from A. fumigatus was only 40% active. The pH optimum of the xylanases was acidic (4.5–5.5). The pH stability for the xylanase from A. fumigatus was higher at pH 6.0–8.0, while the enzyme from A. niveus was more stable at pH 4.5–6.5. Crude enzymatic extracts were used to clarify cellulose pulp and the best result was obtained with the A. niveus preparation, showing kappa efficiency around 39.6% as compared to only 11.7% for that of A. fumigatus.Keywords
This publication has 27 references indexed in Scilit:
- Corncob-Induced endo-1,4-β-d-Xylanase of Aspergillus oryzae MTCC 5154: Production and Characterization of Xylobiose from GlucuronoxylanJournal of Agricultural and Food Chemistry, 2008
- Application of thermoalkalophilic xylanase from Arthrobacter sp. MTCC 5214 in biobleaching of kraft pulpBioresource Technology, 2007
- Effect of cellulase-free xylanases from Acrophialophora nainiana and Humicola grisea var. thermoidea on eucalyptus kraft pulpProcess Biochemistry, 2005
- Xylanases from fungi: properties and industrial applicationsApplied Microbiology and Biotechnology, 2005
- Purification and biochemical characterization of two xylanases produced by Aspergillus caespitosus and their potential for kraft pulp bleachingProcess Biochemistry, 2004
- Influence of temperature on the properties of the xylanolytic enzymes of the thermotolerant fungus Aspergillus phoenicisJournal of Industrial Microbiology & Biotechnology, 2004
- Rhizopus microsporus var. rhizopodiformis : a thermotolerant fungus with potential for production of thermostable amylasesInternational Microbiology, 2003
- Thermostable and alkaline-tolerant microbial cellulase-free xylanases produced from agricultural wastes and the properties required for use in pulp bleaching bioprocesses: a reviewProcess Biochemistry, 2003
- Handbook of enzyme biotechnology, 2nd edn.Analytica Chimica Acta, 1986
- Use of Dinitrosalicylic Acid Reagent for Determination of Reducing SugarAnalytical Chemistry, 1959