title: Photobioreactors in Life Support Systems.
abstract: Life support systems for long-term space missions or extraterrestrial installations have to fulfill major functions such as purification of water and regeneration of atmosphere as well as the generation of food and energy. For almost 60 years ideas for biological life support systems have been collected and various concepts have been developed and tested. Microalgae as photosynthetic organisms have played a major role in most of these concepts. This review deals with the potentials of using eukaryotic microalgae for life support systems and highlights special requirements and frame conditions for designing space photobioreactors especially regarding illumination and aeration. Mono- and dichromatic illumination based on LEDs is a promising alternative for conventional systems and preliminary results yielded higher photoconversion efficiencies (PCE) for dichromatic red/blue illumination than white illumination. Aeration for microgravity conditions should be realized in a bubble-free manner, for example, via membranes. Finally, a novel photobioreactor concept for space application is introduced being parameterized and tested with the microalga Chlamydomonas reinhardtii. This system has already been tested during two parabolic flight campaigns.
authors.affiliation: Department Bioprocess Engineering, KIT, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, Karlsruhe, Germany.
authors.forename: Ines
authors.initials: I
authors.lastname: Wagner
authors.affiliation: OHB Ag Life Sciences, Universitätsallee 27-29, Bremen, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Braun
authors.affiliation: Gravitational Biology, DLR, Königswinterer Str. 522-524, Bonn, Germany. Klaus.Slenzka@ohb-system.de.
authors.forename: Klaus
authors.initials: K
authors.lastname: Slenzka
authors.affiliation: Department Bioprocess Engineering, KIT, Karlsruhe Institute of Technology, Fritz-Haber-Weg 2, Karlsruhe, Germany.
authors.forename: Clemens
authors.initials: C
authors.lastname: Posten
mesh_terms: D061249:Batch Cell Culture Techniques / Q000295:instrumentation*; D049109:Cell Proliferation / Q000502:physiology / Q000528:radiation effects; D016825:Chlamydomonas reinhardtii / Q000166:cytology / Q000254:growth & development* / Q000528:radiation effects; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008021:Life Support Systems / Q000295:instrumentation*; D008027:Light; D008029:Lighting / Q000295:instrumentation; D058433:Photobioreactors / Q000382:microbiology*; D013026:Space Flight / Q000295:instrumentation*; D014893:Weightlessness
keywords: Bubble-free membrane aeration; Chlamydomonas reinhardtii; Energy efficiency; Microgravity; Mono-/dichromatic illumination; Photobioreactor