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With the energy crisis and environmental pollution problems have become increasingly prominent, the world's energy structure is undergoing change mainly from fossil energy to renewable energy. Biomass resources into system leading technology platform of the Third World energy revolution. In this context, the fuel ethanol has been regarded as the best alternative and save gasoline fuel, especially cellulosic ethanol as the best liquid fuel and eco-efficient industrial biotechnology research. This topic for efficient cellulose degrading bacteria as a starting point, from a sample of rotting straw, leaves and pollution mushroom bags, filter out the 68 fast-growing selection medium filter paper as sole carbon source, ulceration spot strain, and then by Congo red screening plate 32 further identification, access to a large circle of hydrolysis strains. On this basis, the straw weight loss rate and enzyme production was measured by liquid medium observe the collapse of the filter paper as sole carbon source to the filter paper and straw as sole carbon source liquid fermentation medium, the final screening to efficiently degradation of cellulose 4 strains of aerobic bacteria F-1, F-7, J-1, J-7, wherein the F-1 and F-7 for bacteria, J-1 and J-7 fungi. F-7 of bacteria and fungi J-7 strains cellulose degradation bacteria liquid fermentation single factor optimization experiments and found that bacterial F-7 in liquid fermentation medium optimum conditions: pH 5.0, incubation temperature 36 ° C, speed 150 r / min, inoculum size of 15%, the addition of 1% yeast extract, ammonium sulfate as the nitrogen source, then CMC enzyme activity reached the highest value of 30.28 U, 10.7% higher than before the optimization of the conditions. Fungi J-7 in liquid fermentation medium optimum conditions: pH 5.0, incubation temperature to 36 ° C, 10% speed 150 r / min, inoculum size, addition of 1% yeast extract, ammonium sulfate as the nitrogen source, CMC enzyme activity reached a maximum value of 70.3 U, 25.3% higher than before the optimization of the conditions. J-7 the most effective the stepwise temperature processing is then cultured for 36 h in 45 ° C in 28 ° C for enzyme production, enzyme activity up to a 74.7 U, 5.8% higher than the the case constant temperature at 28 ℃. The papers on the use of straw ethanol fermentation conditions for the preliminary study to determine the best J-7 cellulose degradation time of 72 h, and then inoculated with yeast inoculum size of 15% of the anaerobic fermentation for 24 h, the resulting The highest concentration of ethanol in the fermentation broth was 12.92 mg / ml. Effectively improve the efficiency of straw degradation of cellulose and through batch add liquid to increase the yield of ethanol. In ethanol fermentation system, initially adding 50% of the culture solution, and then the culture medium at 24 h and 36 h, respectively, supplemented with 25% most conducive to the production of ethanol, the ethanol concentration may be as high as 13.56 mg / ml, more than added in one All the culture medium is 6.8% higher. Of this research through the optimization of J-7 and F-7 straw degradation conditions in a relatively short period of time efficient degradation of cellulose, in particular, the use of J-7 degradation of straw saccharification liquid fermentation production of ethanol to obtain a good fermentation effect is of great significance in terms of resource development and use cellulose and cellulose fermentation to produce ethanol.
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