混凝土修复功能菌Bacillus cohnii DSM6307芽孢发酵条件优化

1)深圳大学生命科学学院,深圳518060; 2)深圳大学土木工程学院,深圳518060

矿化微生物; 嗜碱芽孢杆菌; 芽孢形成; 优化条件; Plackett-Burman设计; 中心组合设计

Optimization of spore production condition of concrete self-healing bacterium Bacillus cohnii DSM6307
Ke Jinlong1, Peng Hui1, Liu Bing1, Deng Xu1, and Xing Feng2

Ke Jinlong1, Peng Hui1, Liu Bing1, Deng Xu1, and Xing Feng21)College of Life Science, Shenzhen University, Shenzhen 518060, P.R.China2)College of Civil Engineering, Shenzhen University, Shenzhen 518060, P.R.China

mineralized microbes; alkaliphilic Bacillus sp.; spore forming; condition optimization; Plackett-Burman design; central composite design

DOI: 10.3724/SP.J.1249.2015.02145

备注

对嗜碱科式芽孢杆菌(alkaliphilic Bacillus cohnii, DSM6307)芽孢形成的影响因素进行了研究.单因素实验结果表明,蔗糖为最适碳源,最佳质量浓度为1.0 g/L; 牛肉膏为最适氮源,最佳质量浓度为3.0 g/L; Mn2+最适质量浓度为3.2 mg/L; Mg2+最适质量浓度为0.12 g/L; 最适温度为30 ℃; 装液量为50 mL(250 mL锥形瓶).运用Plackett-Burman法研究了碳源、氮源、微量元素、温度和装液量5个因素对DSM6307产芽孢数的影响,结果表明,碳源、氮源和Mn2+是影响DSM6307芽孢产量的显著因子.运用中心组合设计实验对这3种显著因子进行优化后,应用响应面模型测出蔗糖、牛肉膏和Mn2+的最优质量浓度分别为1.30 g/L、3.29 g/L和11.48 mg/L,预测芽孢数为1.67×109 mL-1.在此优化条件下,实验得到的芽孢数为1.50×109 mL-1,与预测值接近.

This paper investigates the influential factors of the spore production of alkaliphilic Bacillus cohnii(DSM6307). Firstly, we employed a single factor optimization method and obtained the results that the optimum carbon source is sucrose with the suitable concentration of 1.0 g/L; the optimum nitrogen source is a beef extract with a suitable concentration of 3.0 g/L; the optimal concentration of Mn2+ is 3.2 mg/L, and the optimal concentration of Mg2+ is 0.12 g/L; the suitable temperature is 30 ℃, and the loading volume is 50 mL in a 250 mL conical flask. Then the Plackett-Burman design of the experiment reveals that the carbon source, nitrogen source and Mn2+ are the significant factors among the 5 factors of carbon source, nitrogen source, microelement level, temperature and the loading volume. Finally, we performed further optimization with central composite design and response surface analysis, and it is found that the spore production of DSM6307 is 1.67×109 mL-1 with optimized concentrations of sucrose, beef extract and Mn2+ being 1.30 g/L, 3.29 g/L and 11.48 mg/L, respectively. Under such optimized conditions, the actual spore production in our experiment is 1.50×109 mL-1 and is close to the predicted one.

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