Utilization of three types of effluent waters from a brewery in microalgae cultivation for algae-based lutein production

Wastewater utilization for high value microalgal biomass production is potentially the most economical route for its fuel and feed applications. In this study, the suitability of various stages brewery wastewaters for economic microalgae cultured was studied to realize bioactive product synthesis and wastewater purification dual goals. First, through economic algae strains screening, the robust strain FACHB-1068 for brewery wastewater was obtained, in which the biomass concentration was high as 0.76 g/L after 7-day culture. The following nutrient removal results of FACHB-1068 show that over 93% of NH₄-N (from 24.1 to 1.54 mg/L) and 74% of TP (from 7.39 to 1.91 mg/L) were removed in RW after only 3-day culture. Meanwhile, 1.9 mg/L lutein was harvested in RW. Next, processing time was extended and it was found that the lutein production was high as 3.3 mg/L in 10-day ICW culture with efficient ammonium (94.2%, from 23.6 to 1.37 mg/L) and phosphate (91%, from 7.35 to 1.1 mg/L) removal. And in the low nutrient discharged wastewater, there were also 2.58 mg/L lutein production after 10-day culture. Finally, the investigation of the environmental factors’ effects shows that moderate luminosity (150-200 μ photons/m² s¹) and proper addition of phosphate and ferric can lead to the highest biomass (1.09 g/L) and lutein productivity (4.2 mg/L) in ICW culture.