Agroindustrial biomass for xylanase production by Penicillium chrysogenum: Purification, biochemical properties and hydrolysis of hemicelluloses

Background: In this work, the xylanase production by Penicillium chrysogenum F-15 strain was investigated using agroindustrial biomass as substrate. The xylanase was purified, characterized and applied in hemicellulose hydrolysis. Results: The highest xylanase production was obtained when cultivation was carried out with sugar cane bagasse as carbon source, at pH 6.0 and 20 degrees C, under static condition for 8 d. The enzyme was purified by a sequence of ion exchange and size exclusion chromatography, presenting final specific activity of 834.2 U.mg.prot(-1). T molecular mass of the purified enzyme estimated by SDS-PAGE was 22.1 kDa. The optimum activity was at pH 6.5 and 45 degrees C. The enzyme was stable at 40 degrees C with half-life of 35 min, and in the pH range from 4.5 to 10.0. The activity was increased in the presence of Mg+2 and Mn+2 and reducing agents such as DTT and beta-mercaptoethanol, but it was reduced by Cu+2 and Pb+2. The xylanase presented K-m of 2.3 mM and V-max of 731.8 U.mg.prot(-1) with birchwood xylan as substrate. This xylanase presented differences in its properties when it was compared to the xylanases from other P. chrysogenum strains. Conclusion: The xylanase from P. chrysogenum F-15 showed lower enzymatic activity on commercial xylan than on hemicellulose from agroindustry biomass and its biochemistry characteristics, such as stability at 40 degrees C and pH from 4.0 to 10.0, shows the potential of this enzyme for application in food, feed, pulp and paper industries and for bioethanol production. (C) 2018 Pontificia Universidad Catolica de Valparaiso. Production and hosting by Elsevier B.V. All rights reserved.