枯草芽孢杆菌wlcl芽孢生成条件优化及净水作用研究

Study on the Optimization of Formation Condition of Bacillus subtilis wlcl Spore and Its Water Purification Effect

[目的]提高枯草芽孢杆菌的产量并降低生产成本。[方法]利用旋转回归法研究豆饼粉、葡萄糖对枯草芽孢杆菌（Bacillus subti-lis）液体发酵生产芽孢的影响。[结果]芽孢形成率与豆饼粉和葡萄糖的回归方程为：Y1=35.8-2.185 65X1＋0.685 666X2-5.962 504X1X1-1.25X1X2-3.462 499X2X2,其因变量和自变量之间的线性关系显著,决定系数为86.21%。豆饼粉为1.2%,葡萄糖为1.0%时,芽孢形成率最大,估计为89%。试验池的COD值从第1天的9.85 mg/L下降到第11天的7.87 mg/L,而对照池的COD值从第1天的8.95 mg/L上升到第7天的9.69 mg/L后再下降。试验池中亚硝酸盐浓度从0.088 mg/L下降到0.059 mg/L,而对照池中亚硝酸盐浓度从0.072 mg/L上升到0.085 mg/L。试验池水体pH值在7.5-8.4的范围内变动,而对照池水体pH值普遍高于试验池,最高达8.7。对照池中H2S浓度在0.008-0.030 mg/L的范围内,而试验池水中H2S浓度从试验初期的0.060 mg/L下降到第11天的0.015 mg/L。[结论]培养基中的碳源和氮源是芽孢生成的重要因素。

[ Objective ] The purpose was to enhance the yield of Bacillus subtilis and reduce its production cost. [ Method] The influences of powder of soybean cake and glucose on producing spore by liquid fermentation with B. subtilis were studied by rotary regression design. [ Result] The regression equation between, formation rate of spore and powder of soybean cake, glucose was Y1 = 35. 8 - 2. 185 65X1 ＋ 0. 685 666X2 - 5. 962 504X1 X1 - 1.25X1 X2 - 3. 462 499X2X2, the linear correlation between its dependent variable and independent variable was significant and its decision coefficient was 86.21%. When the powder of soybean cake was 1.2% and the glucose was 1.0% , the formation rate of spore was greatest and estimated to be 89%. The value of COD in the experimental pool decreased from 9.85 mg/L of the 1st day to 7.87 mg/L of the 1 lth day, but that in the controlled pool increased from 8.95 mg/L of the 1st day to 9.69 mg/L of the 7th clay and then decreased. The conch, of nitrite in the experimental pool decreased from 0.088 mg/L to 0. 059 mg/L and that in the controlled pool increased from 0. 072 mg/L to 0.085 mg/L. The pH value of water body in the experimental pool varied in the range of 7.5 - 8.4. The pH value of water body in the controlled pool was generally higher than that in the experimental pool and its highest value was up to 8.7. The conch, of H2S in the controlled pool was in the range of 0. 008 -0.030 mg/L and that in the experimental pool decreased from 0.060 mg/L of the initial stage of experiment to 0.015 mg/L of the 1 lth day. [ Conclusion] The carbon and nitrogen sources in medium were important factors for the formation of spore.