Document Details
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Document Type |
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Thesis |
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Document Title |
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Biodegradation of Kerosene Pollutant by Mono and Mixed Microbial Cultures التحلل الحيوي لملوث الكيروسين بواسطة المزارع الميكروبية الوحيدة والمختلطة |
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Subject |
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Statistics department |
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Document Language |
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Arabic |
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Abstract |
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Kerosene fuel composed of a complex mixture of hydrocarbons (9-20 carbon atoms). It has lead to hazardous effect to the environment and cause some specific harmful effects in human health such as irritation to eye, skin and respiratory system and some carcinogenic effects. It is a common pollutant to water and soil environment. In the present work, isolation of bacteria and filamentous fungi capable of kerosene biodegradation from the industrial region in south Jeddah, Saudi Arabia was conducted. The isolated bacteria were: Acinetobacter sp. , Alcaligenes sp. , Bacillus sp. , Escherichia coli , Flavobacterium sp. , Micrococcus luteus , Pseudomonas aeruginosa and P.fluorescens , while the isolated fungi were: Alternaria alternata , Aspergillus flavus , A. fumigatus , A. niger , A. ustus , Penicillium corylophilum , P. fellutanum and Rhizopus rhizodopodiformis. M.luteus was the most active bacteria for degradation of 2% kerosene and P.aeruginosa was less efficient, while A.flavus was the most active degrading fungus and A. niger was less active. The presence of surfactant (Tween 80) significantly increase the biodegradation activities by more than 30% by the test organisms. Time course biodegradation of kerosene indicated that 3 days of fermentation was efficient to degrade 90% or more of kerosene by M.luteus and P.aeruginosa , while 6 days was satisfactory for the same goal by A.flavus and A.niger . Mixed culture technique of the two bacteria or the two moulds or a bacterium and a mould indicated that at the late fermentation period mono culture of either a bacterium or a fungus is more efficient to biodegrade kerosene. Of different 8 fermentation media, Bushnell-Haas medium proved to be the most favor for the biodegradation of kerosene by the two bacteria, while Bacosa et al medium was the most efficient for kerosene degradation by A.flavus and A.niger. Statistical design of two phase multifactorial optimization (Plackett-Burman and Box-Behnken) were carried out to optimize cultural conditions to increase the efficiency of A.flavus (most potent tested organism) for biodegradation of 2% kerosene. The proposed Plackett-Burman optimization reduced the fermentation period by about 14% and completely biodegrade kerosene. It also indicated that the most significant three factors in the biodegradation process were volume of medium/flask, (NH4)NO3 and pH value. The investigation of these factors using Box-Behnken design (response surface methodology) resulted in 100% degradation of 2% kerosene after 111.3 h (instead of 124 h) of fermentation. In an applied trial, hydrocarbon free soil contaminated with 2.5% (v/w) kerosene become completed kerosene free when amended with A.flavus under the best optimized conditions. |
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Supervisor |
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Prof. Khaled Mohamed Ghanem |
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Thesis Type |
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Master Thesis |
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Publishing Year |
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1433 AH
2012 AD |
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Co-Supervisor |
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Prof. Saleh Mohamed Al-Garni |
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Added Date |
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Saturday, March 24, 2012 |
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Researchers
| أحمد فوزي الحمودي | Al-Homodi, Ahmad Fawzi | Researcher | Master | |
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