Wave-mixed and orbitally shaken single-use photobioreactors for diatom algae propagation

Although vertical column, flat‐plate, tubular, bubble column and airlift photobioreactors are widely used for the cultivation of diatoms, it has been shown that bubble‐induced hydrodynamic stress created in these types of bioreactor can damage cells. Therefore, three single‐use surface‐aerated bag bioreactors, known for their outstanding results in cultivating shear‐sensitive mammalian cells, were for the first time investigated for their suitability in growing the model microalgae Phaeodactylum tricornutum. All of the systems, which were additionally aerated with CO₂ and equipped with illumination systems providing different light qualities, guaranteed a 22‐ to 43‐fold increase in cell density within seven days, without any addition of cell protection agents or changes in cell morphology. Maximum cell density and dry biomass were achieved in the orbitally shaken 2D‐bag by using cool‐white fluorescent tubes.