Valorization of Spent Media Using Green Microalgae and Feedstock Production.

The coupling of biomass production for nutrients removal of anaerobic broth (EAB) is thought to be an economically feasible option for the cultivation of microalgae. The feasibility of growing microalgae in using EAB high in nutrients for the production of more biomass was examined. EAB comprised of nutrient-abundant effluents, which can be used to produce microalgae biomass and remove environment pollutant simultaneously. In this study, 21gr (cc1690) was cultivated in different diluted anaerobic broth supplemented with trace elements under mixotrophic and heterotrophic conditions. The results showed that . grown in 1×, 1/2×, 1/5× and 1/10× anaerobic broth under mixotrophic conditions exhibited specific growth rates of 2.71, 2.68, 1.45, and 1.13 day, and biomass production of 201.9, 184.2, 175.5, and 163.8 mg L, respectively. Under heterotrophic conditions, the specific growth rates were 1.80, 1.86, 1.75, and 1.02 day, and biomass production were 45.6, 29.4, 15.8, and 12.1 mg L, respectively. The removal efficiency of chemical oxygen demand, total-nitrogen and total-phosphorus from 1× anaerobic broth was 21.51, 22.41, and 15.53%. Moreover, the dry biomass had relatively high carbohydrate (44.3%) and lipid content (18.7%). Therefore, this study provides an environmentally sustainable as well economical method for biomass production in promising model microalgae and subsequently paves the way for industrial use.