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Cellulosic material nature richest renewable resources , cellulase degradation of natural cellulosic substances into glucose , and then converted into biofuel and other high value-added products , and facing the world today can effectively alleviate food the energy crisis and environmental pollution , and other issues of great significance for the sustainable development of the human . Cellulase producing bacteria producing the low activity Enzymes component is not entirely bottleneck cellulase not been utilized extensively . The fermentative production of a high activity cellulase has important significance . State Key Laboratory of Microbial Technology, Shandong University cellulase producing fungus Penicillium decumbens JU-A10 as fermentation strains , in order to the steam explosion Gramine cellulosic feedstocks , cellulosic enzyme fermentation process conditions . Arundo donax is a fast-growing , high cellulose content of the straw crops is good cellulase fermentation substrate . First, the thesis of seed age , inoculum size , initial pH, temperature, loading capacity , speed , of Arundo donax concentration and polyurethane foam on the production of the enzyme to conduct a study to determine the Penicillium JU-A10 liquid fermentation production of cellulase is the most appropriate : the seed age 32h, inoculum 10% , initial pH = 5 , temperature 30 ℃, loading capacity 100 mL of speed 200rpm , Arundo donax % . Under these conditions , the filter paper activity 7.43IU/ml CMC enzyme activity 11.77IU/ml . The upgrade 1.0 units and 1.4 units , respectively, compared with the original 6.48IU/ml and 10.35IU/mL . Second, examine feeding cellulase fermentation . Have the effect of bran , Arundo donax , microcrystalline cellulose , additional on the enzyme activity increased . The best feeding time for 72h. Arundo donax , microcrystalline cellulose best complement quantity of 1% microcrystalline cellulose prices than the Arundo donax expensive , taking into account the cost problem , more suited to the addition of Arundo donax as the carbon source . Filter paper activity 10.25IU/ml, and comparable control 2.0 units . Complement plus microcrystalline cellulose filter paper activity 7.98IU/ml, 2.0 units higher than the control CMC enzyme activity 12.28IU/ml , an increase of 1.8 units , compared with the control enzyme activity . 72h , respectively, supplemented with 0.2% ammonium sulfate , 0.2 % sodium nitrate enzyme activities are increased . The filter paper activity , respectively 8.05IU/ml 0.9 8.01IU/ml than control units CMC enzyme activity , respectively, for 13.93IU/ml , 13.78IU/ml compared with the control enzyme activity or less .
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