更新率对小球藻生长与油脂积累的影响

Effects of Renewal Rates on the Growth and Lipid Accumulation of Chlorella under Semi-continuous Cultivation

文章采用柱状光反应器培养小球藻Chlorella sp. HQ,确定了最优光反应器操作条件,探究了半连续培养更新率对小球藻生长及油脂积累的影响。结果表明高初始接种密度、低曝气速率、培养基灭菌更有利于小球藻的生长,用于半连续培养的最佳操作条件为初始接种密度2×10~6个/mL,曝气速率1 L/min,培养基不调pH且经过灭菌。采用半连续培养模式,不同更新率下小球藻获得最大生长率时的最佳更新率为30%;从更新率与油脂含量、TAGs浓度的拟合曲线得出获得最大油脂积累量的最佳更新率为21%。可见调节更新率可获得高微藻生物量及高油脂产量,研究结果为利用小球藻大规模生产生物质转化生物柴油提供了数据基础。

Column photoreactors were used to cultivate Chlorella sp.HQ and the optimal photoreactor operating conditions were determined.Then the effects of renewal rate on the microalgal growth and lipid accumulation were investigated under semi-continuous cultivation.The results showed that high initial inoculation density,low aeration rate,medium sterilization were more conducive to microalgal growth.The optimal operating conditions for semi-continuous cultivation were 2×10~6 cells/mL of initial inoculation density,1 L/min of aeration rate,not adjusting pH,the medium sterilized and not adjust pH value.In the semi-continuous cultivation mode,the optimal renewal rate of the microalga at the maximum growth rate was 30%.From the fitting curve of the renewal rate and the lipid content and TAGs concentration,the optimal renewal rate was 21%at the maximum lipid accumulation.The results indicated that the high microalgal biomass and high lipid yield can be obtained by adjusting the renewal rate,which provides a reference and data basis for large-scale biomass production and biodiesel conversion using Chlorella sp.HQ.