Effects of cultivation strategies on the cultivation of Chlorella sp. HQ in photoreactors  

作　　者：Xiaoya Liu Yu Hong Peirui Liu Jingjing Zhan Ran Yan 

机构地区：[1]Beijing Key Laboratory for Source Control Technology of Water Pollution,College of Environmental Science and Engineering,Beijing Forestry University,Beijing 100083,China

出　　处：《Frontiers of Environmental Science & Engineering》2019年第5期151-161,共11页环境科学与工程前沿（英文）

基　　金：the Fundamental Research Funds for the Central Universities(No.2017ZY43)and the National Natural Science Foundation of China(No.51571034).

摘　　要：The effects of cultivation strategies (including autotrophic cultivation (AC), heterotrophic cultivation (HC), fed-batch cultivation (FC), heterotrophic+ autotrophic two-stage cultivation (HATC), and heterotrophic+ mixotrophic two-stage cultivation (HMTC)) on the growth and lipid accumulation of Chlorella sp. HQ and its total nitrogen (TN) and total phosphorus (TP) removal in secondary effluent were investigated in column photoreactors. The results showed that the TN and TP removal rates ranged between 93.72%–95.82% and 92.73%–100%, respectively, under the five different strategies. The microalgal growth potential evaluated by the maximal growth rate (Rmax) was in the order of HMTC>HC>FC>AC>HATC. The values of biomass, total lipid yield, triacylglycerols (TAGs) yield, and total lipid content of the microalga cultivated in the last 5 d increased significantly, but the TAGs productivities of the five strategies were lower than those in the first 7 d. Compared with all the other cultivation strategies, the TAGs productivity and yield after 12 d of cultivation under the heterotrophic condition reached the highest values accompanying the highest level of intracellular reactive oxygen species (ROS), in which the TAGs yield reached 40.81 mg/L at the end of the cultivation period. The peaks in TAGs yield and ROS level suggested that HC was beneficial for lipids accumulation via regulating the cellular redox status and exerting ROS stress on microalgal cells. In summary, HMTC was the best cultivation strategy for improving the microalgal biomass and HC was the best strategy for microalgal TAGs accumulation to produce biodiesel.

关 键 词：CHLORELLA sp.HQ CULTIVATION strategy LIPIDS Nitrogen REMOVAL Phosphorus REMOVAL Reactive oxygen species 

分 类 号：X70[环境科学与工程—环境工程]