本试验采用响应面法对里氏木霉（T richoderma reesei）固体发酵产α‐半乳糖苷酶的培养条件进行了优化。首先根据单因素实验设计Plackett‐Burman试验筛选出影响产酶的3个主要因素：玉米芯与甘蔗渣的碳源配比、牛肉膏与硫酸铵的氮源配比和发酵初始pH。在此基础上运用最陡爬坡路径法逼近最大响应值区域，最后利用响应面分析法确定主要因子之间的交互作用及最佳培养条件。结果表明，里氏木霉固体发酵产α‐半乳糖苷酶的优化培养条件为：碳源配比即玉米芯与甘蔗渣比值为3.86，氮源配比即牛肉膏与硫酸铵之比1.17，初始p H为9.12。优化后，里氏木霉固体发酵产α‐半乳糖苷酶的酶活可达到342.98 U／g ，与模型预测值353.43 U／g 接近，比优化前的酶活提高113.91％。综上，影响里氏木霉固体发酵产α‐半乳糖苷酶最重要因素分别为碳源、氮源及p H ，三者之间相互影响，分别在碳源配比3.86、氮源配比1.17及初始p H 9.12时α‐半乳糖苷酶酶活最大。%The culture conditions of Trichoderma reesei solid‐state fermentation to produce α‐gal‐actosidase were optimized by response surface method .First of all ,according to the single fac‐tors ,the experiments were designed as Plackett ‐ Burman and three main factorswere selected out :The ratio of corn cob and bagasse carbon source ,the ratio of beef extract and ammonium ni‐trogen source and the fermentation initial pH .On the basis of using the method of the steepest uphill path approximation maximum response area ,the response surface method was used to de‐termine the main factors of the interaction between the main factors and the optimal culture condi‐tions .The results showed that the optimized culture conditions in Trichoderma reesei solid‐state fermentation producing α‐galactosidase were :the ratio of carbon source (namely corn cobsand to bagasse ratio) was 3 .86 ,the ratio of nitrogen source (beef paste to ammonium sulfate) was 1 .17 ,and the initial pH was 9 .12 .After optimization ,the α‐galactosidase activity produced in Trichoderma reesei solid‐state fermentation could be up to 342 .98 U/g and were close to 353 .43 U/g , the model prediction .It was increased by 113 .91% than before optimization .In conclusion ,the most important factors in Trichoderma reesei solid‐state fermentation were carbon source ,nitro‐gen source and pH value ,which interacted each other .The activity of α‐galactosidase was maxi‐mum when the ratio of carbon source was up to 3 .86 ,the ratio of nitrogen source was up to 1 .17 and pH value reach to 9 .12 .
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