الفهرس | Only 14 pages are availabe for public view |
Abstract Lignocellulosic biomass is the most plentiful of all the naturally occurring organic compounds. Conversion of cellulosic polymers into useful products by fermentation involves two stages: firstly conversion of cellulose to glucose by cellulase, and secondly microbial conversion of the resulting glucose to products. The related activities toward cellubiose and β-D-glucosidase depend on the source of the enzyme especially for A. niger. The fascinating aspect of cellobiase produced by A.niger is its higher yield, which is about 46 times that of Trichoderma. The experiments were conducted to obtain β- glucosidase and cellobiase enzyme from the two fungi strains Aspergillus nigerNRRL3 and Aspergillus brasiliensis by using rice straw as main component in fermentation media. The experiments were carried out in the laboratory of Soil, Water and Environmental Instituted, Giza Egypt. To achieve this target the following procedures will adopted: Several agricultural wastes especially rice straw were used as a raw material to isolate microorganisms with capabilities to decompose the raw material cellulose. The isolated microorganisms were purified and screened for the cellulose degradation and for the production of the β- glucosidase enzyme. Two fungal strains were selected that showed strong cellulose degradation and high β- glucosidase enzyme production. The two fungal strains were identified to species level. Nutritional and environmental condition for the β- glucosidase enzyme production by the two fungal strains was optimized. The β- glucosidase enzyme was precipitated and purified. |