High-cell-density heterotrophic cultivation of Chlorella pyrenoidosa for single cell protein

Chlorella based single cell protein (SCP) is a powerful candidate of sustainable protein source. The heterotrophic cultivation has been proved to be a more effective and industrially scalable route for the economical production of the Chlorella biomass, compare to traditional autotrophic cultivation. In this study, the heterotrophic cultivation medium and pulsed feeding strategy were optimized for the enhanced production of Chlorella pyrenoidosa CP2 based SCP. The content of total amino acids, biomass production, biomass productivity of C. pyrenoidosa CP2 respectively reached 50.64 %, 132.13 g/L and 18.87 g/L/d at 5-L fermenter scale. Moreover, the nutrient profile showed that the macronutrient contents, as well as the amino acid compositions and the essential fatty acid proportion of the heterotrophic C. pyrenoidosa CP2 biomass were comparable to those of the autotrophic biomass. The results indicated that the heterotrophic cultivation of C. pyrenoidosa CP2 has great potential for industrial production of microalgae based SCP.