الفهرس 
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Abstract
1. Thirty four species of fungi were examined for their ability to grow under alkaline conditions.
2. Nine species belonging to the genera Alternaria, Aspergillus, Fusarium, Peacilomyces and Penicillium exhibited growth profile of facultative alkaliphilic fungi.
3. These fungi had the potentiality to produce different alkaline detergent enzymes. Aspergillus flavus, Fusarium oxysaporum, Paecilomyes variotii and Penicillium chrysogenum were recorded as the best producers for the alkaline a-amylase, cellulase, lipase and protease, respectively.
4. Growth and production of alkaline detergent enzymes by these four fungi were favorably affected by addition of sodium chloride to the fermentation media. So, they were categorized also as halotolerant organisms.
5. A series of experiments were then conducted to optimize productivity of the four alkaline detergent enzymes at pH 9. The best favorable cultural and environmental conditions governed production of these enzymes in surface cultures were determined as follow:
a-Maximal formation of alkaline amylase by A. flavus (3.3 U/ml) was accumulated in medium contained 6% of soluble starch and 0.6% peptone after 6 days incubation at 30 oC.
B-Highest productivity of alkaline cellulase from Pae. Variotii amounting to 3.4 U/ml was obtained at 30 oC after 7 days of incubation in fermentation medium containing 4% CMC and 4% casein.
C-Optimum yield of alkaline lipase of F. oxysporum (49.1 U/ml) was achieved after 5 days of incubation at 30oC when the fermentation medium contained olive oil and NaNO3 at a concentrations of 0.75% and 0.6 %, respectively.
D-Optimum protease expression (3.8 U/ml) was occurred in presence of 0.9% sucrose and 0.7% casein after 7 days of static fermentation at 30oC.
6. Production of the four alkaline enzymes in solid- state cultures was investigated in a trial to improve the productivity of these enzymes. Four types of natural products i.e. wheat bran, corn bran, wheat straw and crushed rice grain were used in this study. With the exception of the alkaline lipase of F. oxysporum, good increase in yields of the other investigated alkaline enzymes was obtained in comparison with the results of liquid surface cultures.
7. Depending on the fact that not all industrial applications of enzymes require their purified form where many enzyme applications could be performed with crude enzyme preparations, activity and stability of the produced crude enzymes were then studied with respect to both pH and temperature:
a- The alkaline crude α-amylase produced by A. flavus expressed its maximal activity at pH 8 and 30oC. The enzyme retained 80% of its original activity after 10 min at 60oC. After one hour at pH 9, the remaining activity was calculated to be 63% of the original.
B- The alkaline crude cellulase produced by Pae. Variotii and alkaline crude lipase of F. oxysporum expressed its maximal activity at pH 9 and 30oC. The two enzymes retained about 50% of their activities after 10 min at 90oC. They also retained their full activity for at least one hour at pH 9.
c- The alkaline crude protease of P. chrysogenum showed maximal activity at pH 9 and 40 oC. This enzyme retained its activity unaffected for half an hour at pH 9 but retained 95% of the initial activity at pH 8 and 10 for 30 and 10 min, respectively. The enzyme was found to be thermo-tolerant by retaining 50% of its original activity 70oC after exposure for half an hour.
8.Washing properties of the enzyme mixtures of the four fungi were also investigated. The detergent enzyme complex of P. chrysogenum was the best between the investigated four detergent enzyme mixtures. It retained its stability in presence of the commercial detergent and gave the best results of washing test. This was attributed to the dominance of the alkaline protease in this enzyme mixture.
9.The alkaline protease from P. chyrsogenum was purified by dialyzing the CFF against crystals of pure sucrose at 4 oC and pH 9, followed by precipitation with 0.6 saturation (NH4)2SO4. Specific activity of the resulted partially purified preparation was 43.48 U/mg proteins with an overall recovery of 70.89 % and 1.73 purification fold. Purification of the enzyme was completed by gel filtration through sephadex G-100 and ion-exchange chromatography on DEAE-Cellulose. A content of 24.33 % of the original enzyme was finally obtained with about 7-fold purification and specific activity of 192.25 U/mg proteins.
10. General properties of the purified alkaline protease of P. chrysogenum were then investigated:
a-Maximum activity of the purified enzyme was achieved at pH 9 and 40 oC.
B-The enzyme had good stability at pH values ranged between 7 and 10 and high degree of thermal stability at temperatures not more 50 oC.
C-Km value and Vmax of the purified protease were calculated to be 0.71 mM and 70 U/ml, respectively.
D-Alkaline protease activity was enhanced in presence of Ca2+ and Mg2+ and strongly inactivated by Hg+2, Cu+2, Zn+2 and Fe+3. Inhibition caused by arsenate and Hg+2 suggested the participation of –SH group in the catalytic site of the alkaline protease. The enzyme was also confirmed to be non-serine type.
E-The purified alkaline protease of P. chrysogenum was confirmed to contain a sugar moiety indicating that it is conjugated protein (glycoprotein).
F-The purified enzyme preparation was found stable for five days when stored at 4oC. T½ of enzyme activity was found to be three weeks.
G-Silver extraction from X-ray photographic films was achieved successfully at a rate of > 10%.