Domestic wastewater usually contains a large amount of nitrate and phosphate causing eutrophication and water pollution. Microalgae often accumulate nitrogen and phosphorus from nitrate and orthophosphate to produce their biomass. Therefore, the screening of microalgae that are capable of efficiently absorbing nitrate and phosphate is necessary for initial wastewater treatment. This study investigated the ability to absorb nitrate and phosphate of 6 microalgal strains isolated from domestic wastewater. The results showed that two microalgae strains of phylum Chlorophyta, Chlorella sp.1 and Chlorella sp.2, can remove nitrate and phosphate in the experimental scale with absorption efficiency of > 90% and 88%, respectively. The result of this study suggests that these two Chlorella sp.1 and sp.2 can be used as potential agents for management of nitrate and phosphate in domestic wastewater in the upcoming experiments.

Keywords: Nitrate, phosphate, Isolation, microalgae, wastewater treatment