Elevated CO2 impact on growth and lipid of marine cyanobacterium Phormidium valderianum BDU 20041- towards microalgal carbon sequestration

The growth of marine cyanobacteria at elevated CO2 levels is one of the feasible means to bioremediate the greenhouse gases. The present paper describes a marine filamentous cyanobacterium Phormidium valderianum BDU 20041 that can grow at elevated CO2 levels (15%), simulated and actual flue gas. Compared to ambient air and other tested CO2 concentrations, 3% CO2 showed higher biomass productivity, growth rate and carbon fixation rate. The organism was able to tolerate 15% CO2 and the simulated flue gas conditions making it a strong candidate for microalgal carbon capture. The lipid content of P. valderianum BDU 20041 at 15% CO2, simulated and actual flue gas conditions was higher than the ambient air. The conditions tested, i.e. 15% CO2, simulated and real flue gas show that this organism could be a potential entity in curbing carbon emission and a plausible biodiesel feedstock through hydrothermal liquefaction.