| Cellulosic material is the most abundant renewable carbon source in the world. Cellulose may be hydrolyzed using cellulase to produce glucose, and glucose can be used for ethanol production. The utilization of renewable biomass can not only save the foodstuff but also reduce the environmental pollution.In order to obtain mixed-strains producing high-activities cellulase, five excellent strains characteristics were studied using cellilose-congo red medium, solid state fermentation, antagonism relation between two stains. The results indicated that cellulase activities of mixed Trichoderma reesei 3.2942 and Aspergillus niger 3.316 were significant difference (P＜0.05). The optimum inoculating proportion was 1:1.The condition of dilute alkali hydrolyzing cornstalk at laboratory scale was researched. 88.57％removal rates of lignin and 90.14％retention rate of cellulose was obtained at 121℃, 10min, 8.33％solids content, 2％NaOH.Since the production of cellulase was the major contribution to the bioconversion process, the effects of wheat bran and cronstalk ratio, water content ratio, initial pH of medium, particle size, and time on cellulase synthesis were studied. The results showed that the optimum conditions of producing cellulase were follows: cronstalk and wheat bran ratio was 4:1, water contents ratios was 1:3.5, particle size was 0.246mm, the initial pH was 5. Under the above conditions and growed 5d, the activity of FPase was 14.05U/g; growed 7d, the activity of CMCase was 29.40U/g. Compared with sole-fermentation of Trichoderma viride, the activities of FPase and CMCase were increased 48.92％and 43.49％respectively. The 62.95％of total monosaccharide and 21.73％of pentose were obtained from hydrolyzing sugar succus. Dertermination of monosaccharide composition in hydrolyzing sugar succus were glucose and xylose by Paper Chromatography and High Performance Liquid Chromatography.After UV-irradiation, selection, domestication and cultivation, our laboratory attained an excellent Mutation UV2, which can ferment glucose and xylose to fuel ethanol. After 10 passages, fermentation properties were not changed, the result indicated that the strain was stable in heredity.The production technology of Ethanol was optimized by Simultaneous Saccharification and Fermentation. The optimum technical condition as follows: temperature was 38℃, fermentation time was 72h, the amounts of cellulase were 20U/g, inoculation rate was 10％. Under such condition, the transform rate was 0.364 g/g, 10.60％increased than that before technical optimization and 36.14％increased than that fermented by original strain.
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