الفهرس 
Cellulose applicationsOnly 14 pages are availabe for public view
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Abstract
After isolation of halophilic fungi from Qarun lake and testing them for their cellulolytic activity, halophilic Aspergillus niger AUMC 15543 was the best halophilic fungal isolate with cellulolytic activity. The later was used for cellulase enzymes production under submerged fermentation conditions (SmF).
Optimum cellulose concentration ,incubation time, temperature, salinity and initial pH yielded maximum cellulases enzymes, dry weight, extracellular protein and soluble sugars production by A. niger was 1% cellulose, 14 day incubation time, 30°C culture temperature, 15% salinity and pH5, by yielding maximum dry weight, extracellular protein and soluble sugars of (1170.333mg/50ml,1065mg/ml and 585.333mg/ml) respectively and maximum titers of cellulases enzymes fpase, cmcase and ß- glucosidase of(1.704 IU/ml, 0.852667 IU/ml and 2.121333 IU/ml) respectively.
Culture medium with lactose 1% addition yielded higher titers of fpase, cmcase and ß- glucosidase of (2.106333 IU/ml, 1.111667 IU/ml and 2.615333 IU/ml) respectively and higher dry weight, extracellular protein and soluble sugars of (1489.333 mg/50ml, 1376 mg/ml and 886.6667 mg/ml) respectively compared to control, glucose, maltose and sucrose.
Addition of 10µm of MgSO₄.7H₂O, FeSO₄.7H₂O and 1%KH₂PO₄had increased the dry weight, extracellular proteins and soluble sugars as they gave dry weight of (1292.667, 1260.333 and 1312.333 mg/50ml) respectively, it also yielded extracellular proteins of (1179.667, 1145 and 1207.667 mg/ml) respectively, and soluble sugars of (706, 615 and 792 mg/ml) respectively, it also yielded higher titers of cellulase enzymes , as they yielded fpase (1.935 and 2.083667 IU/ml), cmcase (0.955 and 1.011667 IU/ml) and ß- glucosidase( 2.428333 and 2.5006667 IU/ml) for MgSO₄.7H₂O and1%KH₂PO₄ respectively. FeSO₄.7H₂O addition resulting in increasing fpase and decreasing cmcase and ß-glucosidase, as it yielded (2.008667, 0.702333 and 1.901333 IU/ml) respectively.
Yeast extract addission replacing the nitrogen source of the medium (NaNO3) had a positive effect as it increased the dry weight, extracellular protein secretions and soluble sugars of (2122.667 mg/50ml,2014.333mg/ml and 1034 mg/ml) respectively, and for fpase, cmcase and ß-glucosidase (2.875333, 1.482333 and 2.121333 IU/ml) compared to the control.
There for halophilic Aspergillus niger AUMC 15543 could
be used efficiently for cellulases production