海洋小球藻（Chlorella sp.）高密度培养条件优化研究

为提高小球藻（Chlorella sp.）的生物量，须对f/2配方培养基进行响应面优化。首先须确定小球藻培养基的最佳pH值和盐度。在此基础上，利用Plackett-Burman设计方案筛选出影响小球藻生长的3个主要因素分别为NaHCO3、KNO3和维生素B12，然后通过 Box-Behnken 设计试验确定这3个主要因素的最佳质量浓度参数。结果表明，当培养基组成为:NaHCO3 0.93 g/L、MgSO4 0.40 g/L、KNO3 0.46 g/L、K2HPO4 0.020 g/L、维生素B1 0.60 mg/L、维生素B12 1.8 μg/L、生物素 2.0 μg/L时，小球藻经实验室培养72 h后的生物量达到4.5×107个/mL，较优化前提高了32.5%。

Optimization of Culture Condition for High Density of Chlorella sp.

In order to increase the biomass yield of Chlorella sp.,the culture conditions of f/2 medium were optimized by the response surface method.It was found that pH 5 and salinity 40 of the medium were suitable for the algal growth.Three important substrates in the culture medium screened via Plackett-Burman were sodium bicarbonate,potassium nitrated and Vitamin B12,and their concentrations were further optimized by Box-Behnken.The optimized culture conditions were as follows:0.93 g/L of sodium bicarbonate,0.40 g/L of magnesium sulphate,0.46 g/L of potassium nitrate,0.020 g/L of potassium phosphate dibasic,0.60 mg/L of Vitamin B1,1.8 μg/L of Vitamin B12,and 2.0 μg/L of biotin.After optimization,the cell density of the algae cultured for 72 hours was 4.5×107 cell/mL,which was 32.5% more than that in the original culture medium.