| Cellulose is the most abundant organic raw material in the world, and it is the only renewable resource that is available in large quantities. Presently, only a few cellulose are utilized, most of cellulose are wasted and pollute environment. So it has great realistic meaning for human being to solve environment pollution, food shortage and energy crisis that using cellulase produced by microorganism transform cellulose to energy , chemical and food.This paper included : 1) study on the screening out of strain with high cellulase activity and the conditions for enzyme production; 2) culture medium optimization for producing cellulase by Trichoderma koningii ZJ5 and Aspergillius niger ZJ1; 3) study on purification and properties of P -glucosidase: 4) study on cellulase production by mixed culture with Trichoderma koningii ZJ5 and Aspergillius niger ZJ1; 5) research on the kinetics of the hydrolysis of rice straw powder by cellulase; 6) study on fermentation of rice straw to ethanol. The main results were as follows:1) This paper compared the ability of producing cellulase of several fungi when rice straw powder as primary carbon source, Trichoderma koningii ZJ4 can produce relatively high cellulase. The productivity of cellulase of Trichoderma koningii ZJ4 mutant Trichoderma koningii ZJ5 was improved greatly after mutated by ultraviolet and diethyl sulfate. The medium with straw powder as carbon source, (NH4)2SO4 as nitrogen source and straw powder/bran=2: 1 was optimal and the maximum cellulase activity was reached at 28C and pH 5.0 when cultivated 144 hours. The maximum of CMCase, filter paper and 3 -glucosidase activity were 582.6U/mL, 72.56U/mL and 34.62U/mL respectively.2) The properties of CMCase and filter paper enzyme were studied and results as follows: The optimal temperature of CMCase was 50C and it was stable under 50C; The optimal temperature of filter paper enzyme was 50 C and it was stable under 40 C; The optimum pH value of CMCase was 4.5 and it was stable between pH 2.5 and pH 6.0, while the optimum pH value of filter paper enzyme was 5.0 and it was stable in pH 3.5~pH 6.0; Zn2+, A13+, Mg2+ and Mn2+ have active effects on CMCase activity , Mg2+and Mn2+ have active effects on filter paper enzyme activity.3) When rice straw was pretreated by 15% acetic acid after it was smashed to 80 mesh, it can increase cellulase production by Trichoderma koningii ZJ5. When pretreated rice straw powder as primary carbon source, the optimal fermentation medium, which was obtained by orthogonal test was as following (g/L): rice straw powder, 33; wheat bran, 20; barley flour, 23; (NH4)2SO4, 8.4) Response surface methodology was used to optimize medium for cellulase production by Trichoderma koningii ZJ5. The composition of fermentation medium was(g/L): rice straw powder, 33; wheat bran, 15; barley flour, 15; (NH4)2SO4 , 4. The maximum of CMCase, filter paper enzyme and P -glucosidase activity were 765.8U/mL, 155.3U/mL and 39.54U/mL, respectively under the optimized culture medium after 144 hours.5) Response surface methodology was also used to optimize a medium for P -glucosidase production by Aspergillius niger ZJ1. P -glucosidase activity was 403.7U/mL after optimization and higher significant than that in fermentation medium before optimized ( 3 -glucosidase activity was 187.5U/mL) .The optimized composition of fermentation medium was (g/L): rice straw powder, 6.963; wheat bran, 20; barley flour, 16.5; (NH4)2SO4, 2.44; KH2PO4, 0.5; MgSO4-7H2O, 0.5.6) & -glucosidase of Aspergillius niger ZJ1 was purified by Sephadex G-100 and DEAE-Sephadex A-50 chromatography, and its properties and kinetics was studied. Its optimum temperature was 50癈, and it was stable under 40"C. Its optimum pH was 5.5 and it was stable in pH 3.0 ~pH 8.0. Metal cation influence enzyme activity, Zn2\ AI3\ Ca2+ and Mn2+ have active effects on enzyme activity. Km and Vm of P -glucosidasefor salicin as substrate was 4.530mg/mL and 0.06974 mg/ (mL-min) respect...
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