Efficient nitrogen and phosphorus removal from wastewater by screening and constructing a novel Chlorella sp.-Bacillus taeanensis SD148BN12 consortium

Abstract The discharge of wastewater rich in nitrogen and phosphorus were posing a serious threat to ecological balance and human health. In the study, Bacillus taeanensis SD148BN12 with biosafety and capability of aerobic nitrogen removal by assimilation was selected to construct the Chlorella sp.- Bacillus taeanensis SD148BN12 consortium (M-B). Compared with single axenic Chlorella sp. and single Bacillus taeanensis SD148BN12, M-B improved the removal efficiencies of total nitrogen (91.89%) and total phosphorus (94.58%), the biomass yield (0.52 g/L), as well as the contents of carbohydrate and lipid after cultivation in synthetic wastewater. M-B had the high and stable nitrogen removal efficiency at temperature 20-30 ℃, salinity 20-40‰, light intensity 50-200 μmol photons m -2 s -1 , pH 6-9, C/N ratio 1-10, N/P ratio 4-20, N concentration 1-50 mg/L. The conspicuous removal efficiency of nitrogen and phosphorus from actual marine wastewater could be realized by M-B. Meanwhile, the synergistic interaction between Chlorella sp. and strain SD148BN12 was demonstrated by the characteristics of cell growth, photosynthetic activity and material exchange. The study provided an economical and environmentally friendly strategy for efficient removal of nitrogen and phosphorus from wastewater (including the neglected aquaculture wastewater) by establishing a hopeful microalgae-bacteria consortium.