الفهرس 
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Abstract
Ten fungal strains belonging to five genera were isolated from different types of soil collected from different localities.
Aspergillus aculeatus and A. fumigatus var. ellipticus, were the most active galactanase producing fungi compared with the other isolates.
The highest galactanase production was detected after 2 days by two isolates. The effect of different incubation temperatures showed that the maximum enzyme production was recorded at 30ºC for the tested fungi. The pH 6.5 was the optimum for maximal galactanase production by A. fumigatus var. ellipticus and A.aculeatus . Furthermore; the optimum Arabic gum concentration of 1.0% was recorded for maximum A.aculeatus and A. fumigatus var. ellipticus, galactanase production. Also, NaCl and CaCl2 were the most suitable mineral source for production of the optimal galactanase for two isolates.
The optimum incubation period for maximum A. fumigatus var. ellipticus galactanase activity was after 30 min. but the enzyme has maximum activity at 40°C. Km value for A. fumigatus var. ellipticus galactanase was 7.547
mg ml-1 However, the Vmax for A. fumigatus var. ellipticus galactanase was 2.366Uµg-1 Data on the immobilization of Aspergillus fumigatus var.ellipticus galactanase by entrapment indicated good immobilization yield. Furthermore, galactanase immobilized by entrapment on alginate beads has the highest immobilized activity and the highest immobilization yield (52.91%).
The maximum activity was obtained with 0.5 g of immobilized galactanase. In addition, the optimum temperature for maximum immobilized galactanase was (60°C)