Semi-continuous cultivation of indigenous Chlorella sorokiniana for biomass and pigment production

Abstract

The characteristics of microalgae, the composition of the growth medium, cultivation parameters, and the design of photobioreactors should be considered when obtaining biomass and biologically active substances from microalgae. Continuous and semi-continuous cultivation of microalgae at optimal hydraulic retention time (HRT) is one of the most promising approaches to optimizing the accumulation of biomass and desired metabolites. The continuous nutrient supply to photobioreactors avoids nutrient limitation and maintains algal biomass productivity at its maximum level. This study reports the effect of HRT on the growth of Chlorella sorokiniana and nutrient uptake by algal cells. The maximum cell density in the photobioreactor was observed during cultivation at HRT of 5 days, while the concentration of pigments and ammonium uptake remained at a high level at HRTs of 5–2.5 days. The obtained results demonstrate that C. sorokiniana can grow efficiently under semi-continuous cultivation conditions and can be considered to produce valuable metabolites.