Influence of essential nutrient composition of culture media of Chlorella vulgaris on chlorophyll production

This study focused on the concentration of nutrients (nitrogen and phosphorus) and the substitution of Carbon source from Glucose for NaHCO3 affected microalgal growth and chlorophyll a. Microalgal strain of Chlorella vulgaris SAG 211-19 were grown in media that increased or decreased by half of NaNO3 and KH2PO4 and replaced of NaHCO3 with glucose compared to control samples cultured in Bold’s Basal Medium (BBM). The results showed that chlorophyll a concentrations varied with fluctuations in essential nutrients such as nitrogen, phosphorous, and carbon. Specifically, as reducing the concentration of sodium nitrate salt in the exponential phase by half, the chlorophyll a of synthetic microalgae only reached 7.7 mg/L while the control sample was at 12.45 mg/L. Meanwhile, with reducing or increasing KH2PO4 by half in BBM, chlorophyll synthesis was abundant with values recorded for 13.5 or 14.5 mg/L, respectively. Chlorophyll a that was extracted and measured at the end of culture showed the same trend as during the exponential phase, but there was a slight increase in its concentration when the final biomass was harvested. Finally, the chlorophyll a of the microalgal biomass obtained was 11.4 mg/L; 11.7 mg/L; 14.6 mg/L; and 15.75 mg/L, respectively, in culture media where the concentration of NaNO3 or KH2PO4 is increased by one and a half times or reduced by half.