Partial purification of extracellular exo-inulinase from Ulocladium atrum

• Published in: Journal of Genetic Engineering and Biotechnology 2014-06, Vol.12 (1), p.15-20
• Main Authors: Abu El-souod, Soad M., Mohamed, Tarek M., Ali, Ehab M.M., El-badry, Mohammed O., El-keiy, Mai M.
• Format: Article
• Language: English
• Subjects: Inulinase; Purification; Ulocladium atrum
• ISSN: 1687-157X
• DOI: 10.1016/j.jgeb.2014.04.001

Eight fungal species were cultivated on the Czapek liquid medium and a good starting extracellular and intracellular exo-inulinase were selected. Extracellular inulinase from Ulocladium atrum was prepared in the presence of 1% inulin source and 0.2% sodium nitrate as the best carbon and nitrogen sources. Incubation for the U. atrum was increased till it reached its maximum (36U/ml) at the sixth day of incubation at 30°C which was the best temperature for the production of exo-inulinase. Effect of all metal ions inhibited inulase production by U. atrum. Exo-inulinase was purified by using ammonium sulfate precipitation, ion exchange chromatography on DEAE-cellulose. Three active inulinase forms INI, INII and INIII were resolved, each for DEAE cellulose. The specific activity of INI was 1915U/mg protein which represented 2.65-fold purification over the crude extract with 42.8% recovery pooling of INI placed on CM cellulose chromatography and INI was resolved into INIa, INIb and INIc. The specific activity of INIa was 2479.2U/mg protein which represented 3.43-fold purification over the crude extract with 24.2% recovery.