الفهرس 
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Abstract
To avoid negative environmental and economic impact of agricultural wastes, the reuse of agricultural waste is necessary. The problem of agriculture wastes becomes very obvious and aggregated after the harvest of crops. Therefore, utilization of agriculture wastes in any other environmentally friendly way is very important. This study was performed to evaluate the used hydrolyses of agro-wastes as low cost carbon and nitrogen source for use in enzymes and bioethanol production. Some agricultural wastes (Corn cobs, corn stover, sugar can bagasse, sugar beet pulp) were chosen in this study as a carbon source. The chemical analyses of tested wastes showed different composition of cellulose, lignin, hemicellulose, organic matter, organic carbon, nitrogen, ash, fat and total solid. Thirty-five fungal, 25 actinomycetes and 20 bacterial isolates were isolated and investigated for lignocellulotic enzyme activity plate assay. The selected cultures were grown on tested agricultural wastes (5g/100 ml medium) to evaluate their efficiency of biodegradation of these wastes as carbon source by determining soluble sugar and protein in fermentable broth. The results showed that the enzymatic activities were indeed the highest on corn cobs and sugar beet pulp. The selected cultures (3 fungal, 2 bacterial and 3 actinomycetes isolates) were grown of medium containing soybean okara and sesame husk (0.1%N) as nitrogen source with corn cobs and sugar beet pulp as a carbon sources. Aspergillus sp. F24, Bacillus sp. B5 and actinomycetes A25 showed high degradation efficiency. These isolates were inoculated on low–cost-medium containing corn cobs or sugar beet pulp as carbon source and various concentrations (0.2, 0.3 and 0.4%) of soybean okara and sesame husk as a nitrogen source. As a secondary screening, the maximum yield of soluble sugar and protein were obtained on sugar beet pulp and corn cobs mixed with soybean okara (0.3%) or sesame husk (0.3% and 0.4%) inoculated with tested microbial cultures. Different concentrations of corn cobs and sugar beet (5, 10, 15, g/100ml medium) were mixed with optimal concentrations of nitrogen sources and inoculated by fungal (F7, F24) & bacterial (B5) and actinomycetes (A25) isolates. The results showed that ten gram of sugar beet and 10 and 15 g of corn cobs as carbon source achieved high soluble sugar and protein in fermentable broth. The most efficiency fungal Aspergillus sp. F24 and actinomycetes A25 isolates were genetically identified for Aspergillus niger and Streptomyces cellulase. The cellulase, xylanase, laccase activities and soluble sugar were determined in fermentable broth of Aspergillus niger F24, Streptomyces cellulase A25 growing under optimal concentrations of carbon and nitrogen sources during 16 days. The results indicated that cellulase, xylanase and laccase were maximum at 10 - 14 days on sugar beet pulp (10g) or corn cobs (10 & 15) with soybean okara or sesame husk as nitrogen sources, whereas soluble sugar was at 14 days with the same treatments. The sugars content of fermentable broth were identified by HPLC RI Detector. The efficiency of four strains of S. cerevisiae for bio-ethanol production was evaluated on Cheng et al., (2009) medium and sterilized fermentable broth of selected culture. S. cerevisiae (AUMC 14720) gave the highest value of bio-ethanol on fungal fermentable broth after 4 days. Fermentable broth with or without sterilization was used for producing bioethanol by S. cerevisiae (AUMC 14720). It was found that autoclaved fermentable broth achieved the maximum bioethanol production. The low-cost medium was supplemented by salt solution to assay its effect on bioethanol production. Adding of salt solution improved the production by 1.7 & 1.2 fold when using sugar beet pulp and soybean okara for growing the fungal and bacterial strains respectively. Under the optimal condition, S. cerevisiae AUMC 14720 produced the maximum production (16.6 g /L bioethanol) after 72 h. with 41.59% conversion coefficient, 36.36% bioethanol yield and 87.42% sugar utilizing efficiency.