Biomass and Lipid Production of Dinoflagellates and Raphidophytes in Indoor and Outdoor Photobioreactors

11 pages, 4 figures, 1 table

The principal fatty acids from the lipid profiles of two autochthonous dinoflagellates (Alexandrium minutum and Karlodinium veneficum) and one raphidophyte (Heterosigma akashiwo) maintained in bubble column photobioreactors under outdoor culture conditions are described for the first time. The biomass production, lipid content and lipid productivity of these three species were determined and the results compared to those obtained when the strains were cultured indoors. Under the latter condition, the biotic values did not significantly differ among species, whereas under outdoor conditions, differences in both duplication time and fatty acids content were observed. Specifically, A. minutum had higher biomass productivity (0.35 g·L−1 day−1), lipid productivity (80.7 mg lipid·L−1 day−1) and lipid concentration (252 mg lipid·L−1) at harvest time (stationary phase) in outdoor conditions. In all three strains, the growth rate and physiological response to the light and temperature fluctuations of outdoor conditions greatly impacted the production parameters. Nonetheless, the species could be successfully grown in an outdoor photobioreactor and were of sufficient robustness to enable the establishment of long-term cultures yielding consistent biomass and lipid production

We are grateful to the members of the L´Esfera Ambiental Laboratory, Universitat Autònoma de Barcelona, for their help with gas chromatography analyses. We thank S. Fraga for providing the clonal culture AMP4, L.del Río and X. Leal for their help with the experiments and the Experimental Aquarium Area (ZAE) of the ICM-CSIC for the use of their facilities. We gratefully acknowledge the National Scientific and Technical Research Council (CONICYT), Chile, for its support of the scholarship “Beca de Gestión Propia,” which finances the PhD studies of C. Fuentes-Grünewald. The work of E. Garcés and S. Rossi is supported by the Ramon y Cajal award from the Spanish Ministry of Science and Innovation

Peer reviewed