esearchers at Heriot-Watt University, in Edinburgh, have published a report on their study of microalgae cultivated in photobioreactors at different CO2 concentrations and luminescent conditions. Their report is published in Elsevier’s Biomass and Bioenergy, Volume 85, February 2016, Pages 168–177.
This photobioreactor study investigated the influence of CO2 aeration on biomass production, carbon dioxide fixation rate, pH, the cell’s essential elements such as carbon, nitrogen, and hydrogen, as well as lipid content, while under a range of luminescence-modified lighting conditions.
Results showed that, with the exception of the blue lit PBR, increasing CO2 concentrations in the air stream enhanced the fixation rate of CO2 in C.vulgaris. Cyanobacteria cells showed significant tolerance to 15% CO2.
Red luminescent photobioreactors enhanced biomass production, while blue luminescent photobioreactors induced lipid accumulation.
The results obtained demonstrated that the combination of blue light and 15% CO2 provided a condition in which higher rates of lipid accumulation were induced in both algal strains. The highest lipid content observed at this condition was 36.6% obtained in G.membrancea.
Aeration with 15% CO2 enhanced lipid production of G.membranacea to at least twice the amount produced at 5% CO2 in all photobioreactors. The most significant difference between the 5% and 15% CO2 aeration conditions was observed in the yellow PBR, in which the lipid content was enhanced up to six times.
The researchers were Dr. Seyedeh Fatemeh Mohsenpour, Department of Chemical Engineering, and Corresponding Author Dr. Nik Willoughby, Institute for Biological Chemistry, Biophysics and Bioengineering, both at the School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK.