| 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 of 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: study on the screening out of strain with high cellulose activity and the conditions for enzyme production; culture medium optimization for producing by optional bacterium (Z2); research on Z2 and Trichodetma koningii multiple microorganisms for producing cellulose; study on the hydrolysis of rice straw power by cellulose; initial study on fermentation of rice straw to lactic acid. The main results were as follows:1) By three kinds of culture medium, 57 strains of celluloytic microbes were isolated from cow stool, wood, soil, sludge. 7 strains with high cellulase were gained by average growth velocity, filter paper decomposition and counter-action screening methodology, and then one of them was used to co-fermentation experiment and identified.2) Through preparations of rice straw, the optimal saccharification condition of rice straw powder by Z2 which was obtained by the single factor experiment, was of following: rice straw powder which prethreated by 2%NaOH as carbon source and wheat bran =2:1 , the maximum cellulose activity was reach at 30℃, inoculation volume was 0.5ml, rotate speed200r/min, liquid volume 40ml, initial pH5.0, when cultivated 120 hours.3) Rice straw was utilized as main carbon source by multiple microorganisms, the optimal saccharification ferment condition which was obtained by orthogonal test was follows: barm cream as primary nitrogen source, enzyme volume was 0.75ml, pH5.0, solid state material(rice straw powder: wheat bran=5:3) weight was 1.6g, liquid...
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