LAUSR

Abstract Increasing population and urbanization bring along depletion of water resources with notable discharge of industrial and municipal wastewater which is rich in nutrients. Microalgae hold great promise for assimilating the nutrient compounds, particularly the intricate nitrogen (N) and phosphorus (P) compounds from wastewater, resulting in algal biomass enriched with various valuable biomolecules. However, development of strategies involving the cultivation of microalgae for wastewater treatment and production of commodity components is still in its infancy. In this review, the current status of microalgae-mediated wastewater treatment, the existing technological bottlenecks that hamper the effective use of photosynthetic microalgae, and innovative solutions to obviate the shortcomings are discussed. Also, this article highlights the potential use of genetic engineering technologies in overproducing algal biomolecules without impeding cellular biomass accumulation by regulating critical metabolic targets for the development of engineered algal strains. In this context, adaptive laboratory evolution (ALE) could be the promising tool to further empower the engineered strains to mitigate the adverse effect from the wastewater cultivation medium. In summary, this review provides novel insights into the application of genetic engineering strategies for overproducing algal biomass and valuable biomolecules such as lipids and polyunsaturated fatty acids using wastewater in a cost-effective manner.