响应面法优化自养小球藻产生物柴油油脂

利用响应面法对小球藻(Chlorella vulgaris)在2L气升式生物反应器中对自养产生物柴油油脂的培养条件进行了优化。首先用Plackett-Burman方法对10个相关影响因素的效应进行评价并筛选出对产油有显著影响的3个因素:KNO3浓度、温度和CO2浓度;再用最陡爬坡实验逼近最大产油区域;最后由中心组合实验及响应面分析确定了影响产油主要因素的最佳条件为:KNO3浓度0.31g/L,温度26.5℃,CO2浓度6.80%,最高产油量达到0.42g/L,比优化前提高了近2倍。优化后,在10L气升式生物反应器中进行了扩大培养。

Optimization of Autotrophic Cultivation of Lipids Production for Biodiesel by Chlorella vulgaris with Response Surface Methodology

Response surface methodology was used to optimize the autotrophic cultivation conditions for lipids production by Chlorella vulgaris in a 2-L airlift photobioreactor. In the first optimization step, a Plackett-Burman design was used to evaluate the influence of ten related factors and it was found out that KNO3 concentration, temperature and CO2 concentration influenced lipids production significantly. Subsequently, the path of steepest ascent was used to approach the optimal region of the cultivation conditions. In the third step, KNO3 concentration, temperature and CO2 concentration were further optimized using central composite designs and response surface analysis and the optimum conditions were that KN03 concentration was 0.31 g/L, temperature was 26.5 ℃ and CO2 concentration was 6.80%. Under optimum conditions, the lipid yield was 0.42 g/L and it was increased by two times than that under the conditions before optimized. Chlorella vulgaris was cultured in a 10-L airlift photobioreactor under optimum conditions.