Lipid accumulation of Chlorella pyrenoidosa under mixotrophic cultivation using acetate and ammonium.

Acetate and ammonium were used as organic carbon and nitrogen sources, respectively, during mixotrophic cultivation of Chlorella pyrenoidosa . Cell growth, content of neutral lipid (NL), productivity of biomass and total lipid, and fatty acid profiles were investigated. Results showed that C. pyrenoidosa could endure high concentrations of NH 4 + -N (100–200 mg/L) and immediately entered logarithmic growth, when the culture media contained 2.0–10.0 g/L NaAc. The 2.0–10.0 g/L NaAc in the media also resulted in the NL content of 1.87–3.05 mg/10 9 cells, much higher than 0.5 mg/10 9 cells of the controls. The maximum productivities of biomass and total lipid were achieved under 50 and 10 mg/L NH 4 + -N respectively when the 2.0 g/L NaAc was dosed. The fatty acids were mainly composed of C16:0, C16:1, C18:0, and C18:1 under the mixotrophic cultivation, with the higher saturation compared to the controls. [ABSTRACT FROM AUTHOR]