Production and purification of extreme xylanase from Aspergillus flavus AUMC 10331 in sub-merged fermentation

Abstract

Xylan, extracted from oat spelts in a previous work, was assayed by HPLC and used as carbon source for the production of xylanase from Aspergillus flavus AUMC 10331. The produced xylanase was purified using ion exchange resin (IR-120 EP) and gel filtration column of Sephadex G-75 and Sephadex G-100. The purified xylanase showed total activity of 5.5 IU/ml and specific activity of 687.5 IU/mg, and the enzyme purified 156.75 fold with 4.43 % yield. The highest activity at pH 7.0 and 10.5 indicating two xylanases with the most interesting one with a maximum activity at pH 10.5 and 65 °C. The enzyme activity was greatly stimulated by 5 mM of FeSO4 and CuSO4, while slightly inhibited by other metal ions. Km and Vmax were determined as 8.36 mg/ml and 172.4 IU/min respectively. DOI: http://dx.doi.org/10.5281/zenodo.2586103

Keywords

• Xylanase
• Aspergillus flavus
• Fermentation