الفهرس 
AbstractOnly 14 pages are availabe for public view
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Abstract
Different 20 locations of different plant samples and soil conditions were surveyed for microorganisms of cellulolytic activity. A total of 20 bacterial and 20 fungal samples were collected, cultivated, purified and tested for cellulose degradation. The most efficient producers of cellulase were the fungal and bacterial isolates from grape leaves, which were identified molecularly as Aspergillus flavus MH591448 and Pseudomonas aeruginosa KX610179. A more detailed study for optimization of growth conditions for the highest cellulase activity was performed for the higher cellulose-degrading isolates, namely: Aspergillus flavus, Fusarium oxysporum, Pseudomonas aeruginosa and Klebsiella aerogenes. The maximum growth and cellulolytic activity of the tested microorganisms was obtained for cultures on minimal salt nutrition medium, incubation temperature of 35 °C, with initial pH value = 6, without additive co-carbon source, by adding ammonium sulfate as a supporting nitrogen source, after incubation for 2 days for Bacterial isolates and 5 days for fungal isolates on a shaking incubator of 80 rpm. Chemical pre-treatment for delignification of plant wastes raised the percentage of cellulose content available for biodegradation to 87.59 % for sugarcane bagasse after 60 minutes. That arised the efficiency of cellulose hydrolysis by Aspergillus flavus to 452 mg/g of reducing sugars. The most potent surveyed yeast produced 81 mg/g bioethanol on the Aspergillus flavus-hydrolyzed sugarcane bagasse, that was molecularly identified as Saccharomyces cerevisiae NCYC505. Growth conditions were optimized for the highest bioethanol production, by preparing yeast inoculum on 10 % molasses medium, with initial pH value = 6, incubation at 30 °C, for 48 hours, on a shaking incubator at 20 rpm. that were improved by supplement with ammonium sulfate and start with 20 v/v inoculum size to reach a concentration of bioethanol equal to 158 mg/L, which was characterized and tested for purity by GC-MS analysis.