Collagenase was found to be the most important enzyme, produced by mycotic keratitis fungi. Therefore, Aspergillus flavus collagenase enzyme has been purified by ammonium sulphate precipitation, Sephadex G25 and DEAE-cellulose chromatography. Electrophoretic analysis for the purified enzyme indicated one subunit of molecular weight of 70-90 KDa when examining on SDS-PAGE. Cetrimide (cetyl trimethyl ammonium bromide) has been tested against the purified collagenase enzyme and indicated reversible competitive inhibitor (kis = 0.15 mg/ml) with high promising activity. Cetrimide might be used to inhibit mycotic keratitis fungi.

Ulocladium atrum inulinase was immobilized on different composite membranes composed of chitosan/nonwoven fabrics. Km values of free and immobilized U. atrum inulinase on different composite membranes were calculated. The enzyme had optimum pH at 5.6 for free and immobilized U. atrum inulinase on polyester nonwoven fabric coated with 3 percent chitosan solution (PPNWF3), but optimum pH was 5 for immobilized U. atrum inulinase on polyester and polypropylene nonwoven fabrics coated with 1 percent chitosan solution. The enzyme had optimum temperature at 40 degree C for immobilized enzyme on each of polyester and polypropylene composite membranes coated with 1 percent chitosan, while it was 50 degree C for free and immobilized enzyme on polypropylene nonwoven fabric coated with 3 percent chitosan solution. Free U. atrum inulinase was stable at 40 degree C but thermal stability of the immobilized enzyme was detected up to 60 degree C. Reusability of immobilized enzyme was from 38 to 42 cycles of reuse; after this, the immobilized enzyme lost its activity completely. In conclusion, immobilized U. atrum inulinase was considerably more stable than the free enzyme, and could be stored for extended periods.

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 (36 U/ 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 DEAEcellulose. Three active inulinase forms INI, INII and INIII were resolved, each for DEAE cellulose. The specific activity of INI was 1915 U/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 2479.2 U/mg protein which represented 3.43-fold purification over the crude extract with 24.2% recovery. ª 2014 Production and hosting by Elsevier B.V. on behalf