A recent collaboration between the Space Engineering Research Center (SERC) at the Texas A&M Engineering Experiment Station and Dr Halil Berberoglu at the University of Texas at Austin, has led to a proposal to test an innovative bioreactor concept for space life support.
Dr. Berberoglu and his students envisioned a novel system that mimics the way we obtain sap from a maple tree. In this concept, algae cells are grown as photosynthetic biofilms on porous surfaces that keep them hydrated and provide them with the nutrients they need for growing to maturity. A unique aspect of the synthetic tree concept is that it uses interfacial phenomena rather than inertial phenomena (gravity) to drive the transport of mass within the system. With its reduced water requirement and mass, this feature makes the synthetic tree a unique platform for cultivating cells in reduced gravity environments, i.e., space. Dr. Berberoglu and his collaborators at the Exobiology branch at NASA Ames Research Center further developed the synthetic tree system into the Surface Adhering Bioreactor (SABR) for performing air regeneration (mitigation of carbon dioxide and generation of oxygen) using algal biofilms as a first step towards engineering a fully regenerative biological life support system for long duration manned space missions. This is where the SERC entered the picture. Dr. Berberoglu got in touch with the SERC, and personnel including the Director, Chip Hill, and researchers Dr. Frank Little and Dr. Cable Kurwitz visited Dr. Berberoglu at his lab in Austin. Based on this contact, a team was formed with UT Austin, SERC, and NASA Ames and a proposal developed for NASA to develop a working bioreactor for placement on board the National Lab at the International Space Station to conduct SABR experiments. For the proposed effort, the SERC would build the test apparatus and perform all space payload integration services.
SABR Bioreactor concept (L) and productivity monitoring of biofilms with multispectral imaging (R)
Microalgae (unicellular species) are a diverse group of photosynthetic cells that are capable of using solar energy to convert carbon dioxide from the atmosphere into energy dense molecules such as sugars and oils. Dr. Berberoglu sees a terrestrial application of the research for producing renewable biofuel utilizing solar energy without the high energy and water (large volume needed for cultivation) requirements of algae-based biofuel cultivation and harvesting with the current technologies such as artificial ponds or tubular/flat panel photobioreactors. Using the novel cultivation platforms with algal biofilms as photosynthetic biocatalysts mimics the way plants achieve transport of nutrients and bioproducts in their vascular systems and does not require arable land or fresh water resources, providing a promising option for producing domestic biofuels for our energy independence and security. .
. SERC should learn if their proposal is successful this Summer, and is independently investigating collaboration with a different space group on more traditional bioreactor designs.
“Earth is our spaceship where our ecosystem provides us with a fully regenerative biological life support. We want to understand how this ecosystem works, how we interact with it, and how we can engineer similar systems that will help us survive in space… I also believe that these ideas will have major implications on our terrestrial life as our technological impacts on Earth start becoming more significant at global scales.” – Dr. Halil Berberoglu