温度、盐度和pH对小球藻生长率的联合效应

COMBINED EFFECTS OF TEMPERATURE,SALINITY AND pH ON THE SPECIFIC GROWTH RATE OF CHLORELLA

采用中心复合设计(CCD)研究了温度(16—34℃)、盐度[(15—45)‰]和pH(6.0—9.0)对小球藻(Chlorella sp.CHX-1)生长的联合效应。结果表明,温度、盐度与pH的一次、二次效应都对小球藻比生长速率有极显著影响(P<0.01);温度与盐度间、温度与pH间的互作效应对小球藻比生长速率影响显著(P<0.05),而盐度与pH间的互作效应影响不显著(P>0.05);三因子影响度大小依次为:温度>pH>盐度。采用响应曲面法建立了温度、盐度和pH对小球藻比生长速率影响的模型方程,该模型的决定系数0.9759,矫正决定系数0.9542,说明模型的拟合度极高;模型的预测决定系数0.8367,表明可用于预测小球藻比生长速率的变化。通过模型优化和验证试验,得出在温度、盐度和pH组合为26.7℃/25.5‰/7.3时,小球藻比生长速率达到最大值0.69,满意度为0.999。本试验结果可为小球藻生产提供理论指导。

By using central composite design,the join effects of water temperature（16—34℃）,salinity [（15—45）‰],and pH（6.0—9.0） on the growth of Chlorella sp.CHX-1 were examined in this study.The results showed that the linear and quadratic effects of temperature,salinity and pH on the specific growth rate（SGR） of Chlorella were significant（P＆lt;0.01）.The interactive effect of temperature and salinity,interactive effect of temperature and pH were significant（P＆lt;0.05）,but the interaction between salinity and pH was not significant（P＆gt;0.05）.The effect of temperature on the SGR was greater than that of pH,which in turn was greater than that of salinity.Through response surface methodology,a model equation about the relationship of the growth rate to the three factors was established,with the R2,Adj.R2 as highly as 0.9759 and 0.9542,suggesting that the fitting capability of the model was satisfactory.The Pred.R2 reached to 0.8367,demonstrating that the model could be practicably applied for prediction.Through the optimization of the reliable model,the SGR reached its maximum（0.69） when the 3-factor combination was 26.7℃/25.5‰/7.3,with the desirability value being 0.999.These experimental results could offer theoretical reference for the production of the Chlorella.