Quinone Profiles Reflecting Population Dynamics of Denitrifying Phosphate-Accumulating Organisms

Abstract

Selective enrichment of phosphate-accumulating organisms (PAOs) and denitrifying phosphate-accumulating organisms (DNPAOs) was conducted using a sequencing batch reactor (SBR). To elucidate biomarkers for DNPAOs, quinone profiles were monitored during selective enrichment. As a result, a high correlation between the mole fraction of ubiquinone with eight isoprene units (Q-8) and anoxic phosphate uptake ability was observed, indicating that Q-8 was one of the biomarkers for DNPAOs. In addition, the mole ratio of ubiquinones to menaquinones (Q/MK) increased throughout this selective enrichment.