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In this thesis, the high-yielding strains of straw solid-state fermentation were studied , including two parts of the breeding of mold and yeast breeding . Mold starting strain of Trichoderma TR, to explore its optimal conditions of enzyme production , the results showed that the enzyme production the optimum conditions for 132h , the glucose concentration of 0.5% , the ratio of water 1:1.1 , the optimum temperature of 30 ° C , CMC activity 78.6IU / g song , βG activity was 21.0IU / g song , FPA activity 33.6IU the / g song . From Trichoderma After UV mutagenesis , combined with the breeding of the double Tablet separation technology , significantly improved cellulase production , CMC enzyme activity increased from the first 78.6IU / g song to the 235.17IU / g song , βG enzyme activity from 21.0IU / g song up to 91.60IU / g song , FPA enzyme activity 119.56IU / g song from 33.6IU / g song . After after several generations activation determination , genetic traits can be used as a further mutagenic starting strain . The starting strain of yeast 1 #, 2 # , 3 #, 4 # , # 1 and # 3 higher ethanol production capacity of 6.978% and 6.823% , respectively , while 2 # 4 # fermenting power is poor , but they temperature capability , PEG and electric field induced two protoplast fusion technology used in the experiment , five stable integration of the sub- F2 , F5 , F7 , F14, F20 . The this five fusion sub- ploidy , biological characteristics, genetic stability and Simie temperature and fermentation force measurement results show that they are mononuclear stable fusants . Fermentation medium was measured , F5 , F7 , F14, F20 # 38 ° C 1 strain fermentation at 30 ℃ or higher . Multiple integration test found , PEG -induced fusion efficiency up to 3.1 × 10 -6 , and the electric field - induced fusion efficiency of 5.64 × 10 -4 ( pulse intensity 11KV, pulse width of 10μS, the pulse interval for the 10s , the pulse frequency and 3 ) , but both fusion results no significant difference .
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