响应面法优化康宁木霉产纤维素酶的发酵培养基

摘要

采用响应面法对康宁木霉产纤维素酶的发酵条件进行了优化。首先运用Plackett—Burman法筛选出3个影响较大的重要因素，分剐为：葡萄糖，MgSO4·7H2O，MnSO4·H2O。然后进行最陡爬坡实验，确定这3种重要因素的最适质量浓度范围。最后通过Box—Behnken设计，利用Design Expert软件进行回归分析，得出3种因素的交互作用及最佳发酵条件。确定康宁木霉发酵产纤维素酶的最佳发酵培养基为葡萄糖5．97g／L，乳清粉7g／L，玉米浆干粉13g／L，（NH4hSO44g／L，KH2PO48g／L，MgSO4·7H21O．56g／L，CaCl2·2H20O．6g／L，FeS04·7H2O2．5mg／L，ZnSO4·7H200．7mg／L，CoCl2·6H201．9mg／L，MnS04-H2O4．07mg／L，吐温-801．5mL／L，在此培养基下发酵酶活为0．233IU／mL．比优化前提高了35．7％。%The fermenting culture medium for producing cellulase by Trichoderma was optimized by response surface method. Firstly, three most important influencing factors including glucose, MgSO4.7H20 and MnSO4. H20 were selected through Plackett-Burman design, then the path of steepest ascent experiment was adopted to obtain their most suitable mass concentration range, finally, the interaction among and the optimum fermenting conditions of the three factors were determined through Box-Behnken design and regression analysis by Design Expert software. The best fermenting culture medium was composed of 5.97 g/L glucose, 7 g/L whey powder, 13 g/L dry corn steep liquor powder, 4 g/L （NH4）2SO4, 8 g/L KH2PO4, 0.56 g/L MgSO4-TH20, 0.6 g/L CaC12-2H2O, 2.5 mg/L FeSO4 .TH2O, 0.7mg/L ZnSO4.7H20, 1.9 mg/L CoC12.6H20, 4.07 mg/L MnSO4· H2O, and 1.5 mL/L Tween -80. Under the above conditions, cellulase activity could reach 0.233 IU/mL, increasing by 35.7 % than that before the optimization.