LAUSR

The cultivation of microalgae requires the selection of optimal parameters. In this work, the effect of various forms of nitrogen on the growth and productivity of Chlorella sorokiniana AM-02 when cultivated at different temperatures was evaluated. Regardless of the temperature conditions, the highest specific growth rate of 1.26 day−1 was observed in modified Bold’s basal medium (BBM) with NH4+ as a nitrogen source, while the highest specific growth rate in BBM with NO3− as a nitrogen source achieved only 1.07 day−1. Moreover, C. sorokiniana grew well in medium based on anaerobic digester effluent (ADE; after anaerobic digestion of chicken/cow manure) with the highest growth rate being 0.92 day−1. The accumulation of proteins in algal cells was comparable in all experiments and reached a maximum of 42% of dry weight. The biomass productivity reached 0.41–0.50 g L−1 day−1 when cultivated in BBM, whereas biomass productivity of 0.32–0.35 g L−1 day−1 was obtained in ADE-based medium. The results, based on a bacterial 16S rRNA gene sequencing approach, revealed the growth of various bacterial species in ADE-based medium in the presence of algal cells (their abundance varied depending on the temperature regimen). The results indicate that biomass from C. sorokiniana AM-02 may be sustainable for animal feed production considering the high protein yields.