Thermomonospora fusca was chosen as an original strain for screening high yield cellulase mutants. The spore suspension of organism was treated with UV and Co gamma rays. A high cellulase-producing mutant strain AV8 was obtained. Its enzyme production of CMC was up to 0. 679 IU/mL. The activity of mutant strain AV8 was enhanced to 3. 53 times comparing with that of the original strain. Fermentation conditions were investigated. The results showed that the optimal condition for AV8 to produce cellulose enzyme are as follow: the optimal temperature is 55 ℃ , its enzyme production of CMC of the optimal initial PH value is 7. 0, while its enzyme production of FPA of the optimal initial PH value is 8.0, when the culture was incubated for seven days the yield of CMC enzyme reached a high level, and for eight days the yield of FPA enzyme reached the highest level.%本研究以褐色高温单孢菌(Thermomonospora fusca)为出发菌株,通过紫外线和60Co-γ射线联合诱变,获得了一株纤维素酶高产菌株AV8,CMC酶活力达到0.679 IU/mL,与出发菌株相比,其产酶能力提高3.53倍.通过对AV8产纤维素酶的培养条件进行测定,结果显示:产纤维素酶最适应温度为55 ℃;该菌的最适产CMC酶初始PH值为7.0,最适产FPA酶初始PH值为8.0;当培养到第7天时,产CMC酶达到高峰.当培养到第8天时产FPA酶达到高峰.
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