Revisiting nitrogen utilization in algae: A review on the process of regulation and assimilation

Nitrogen is one of the important components for algae and is available in nature in various redox states. Regulation in transport and assimilation of forms or compounds varies considerably in algae. Various transporter proteins and permease enzymes are involved in the uptake of diverse nitrogen sources. Microalga cultivation is dominated by nitrogen source used in the media and their biomass is important for third generation biofuel production. However, mass algal cultivation requires commercial chemicals, which is a costly affair. Using waste like manure or effluent as a resource is a new paradigm that is a sustainable tool to overcome waste disposal which helps in the cut-down cost of commercial products along with bioremediation. This article systematically explored the reaction of algal physiology to different forms of nitrogen. At the molecular level more research is required to know the exact mechanism of assimilation and regulation of nitrogen within the algal cells. © 2020 Elsevier Ltd