Characteristics of lipid biosynthesis of Chlorella pyrenoidosa under stress conditions

Effects of high light, high salt, nitrogen and phosphorus deficiency on growth and lipid production of Chlorella pyrenoidosa were investigated in a flat-plate photoreactor, and the oil quality indexes such as CN, IV, SV, CFPP, DU, and LCSF were also evaluated. The results show that the growth of C. pyrenoidosa was inhibited under the stress conditions, but the intracellular lipid content was significantly increased. Moreover, the combustion performance, oxidation stability, low temperature fluidity, and other oil quality indicators under these nutrient stress conditions were significantly improved. Importantly, it is found that starch was preferentially synthesized by algal cells, while with the prolongation of stress time, starch was gradually degraded, and the degraded carbon skeleton was mainly used for lipid synthesis.