Page 176 - International Space Station Benefits for Humanity, 3rd edition.

greenhouse on the ISS Russian Segment. The to national security, cancer-fighting pharmaceuticals
contributions of S. A. Gostimsky (M. V. Lomonosov and educational tools for students. ADVASC’s novel
Moscow State University), and M. Sugimoto (Okayama air scrubber was designed to remove ethylene from
University, Institute of Bioresources, Okayama, Japan) the chamber atmosphere to increase longevity of the
should be especially noted. produce. Ethylene—a naturally occurring, odorless,
colorless gas given off by plants—hastens the ripening
of fruits and the aging of flowers, thus encouraging
Plant Growth on the International Space decay. In closed growing environments such as a
Station has Global Impacts on Earth spacecraft or terrestrial greenhouse, ethylene builds up
quickly. As a result, plants mature too fast. Removing
Understanding the effects of gravity on plant life is
essential in preparing for human exploration beyond ethylene, therefore, is important to preserving crops
low-Earth orbit. The ability to produce high-energy, not just in space, but also on Earth, where grocers
low-mass food sources during spaceflight will enable and florists have an interest in longer product shelf life.
the maintenance of crew health during long-duration The ethylene-reduction device, also called the ethylene
missions while having a reduced impact on resources “scrubber,” draws air through tubes that are coated in
necessary for long-distance travel. thin layers of titanium dioxide. The insides of the tubes
The Advanced Astroculture™ (ADVASC) investigation, are exposed to ultraviolet light, which creates a simple
led by Weijia Zhou, Ph.D., formerly of the Wisconsin chemical reaction that converts the ethylene into trace
Center for Space Automation and Robotics, University amounts of water and carbon dioxide, both of which
of Wisconsin-Madison, explored the benefits of are actually good for plants.
using microgravity to create custom crops that can KES Science & Technology Inc., a Georgia-based
withstand the inhospitable climates of space, can resist company specializing in sustaining perishable foods,
pestilence, and will need less volume in which to grow. licensed the ethylene-scrubbing technology from the
ADVASC was performed over several ISS expeditions University of Wisconsin. KES partnered with Akida
where it grew two generations of Arabidopsis thaliana Holdings, of Jacksonville, Florida, which now markets
(i.e., a rapidly growing, flowering plant in the mustard the NASA-developed technology as Airocide.
family that has been grown on many space missions), According to the company, Airocide is the only air
and soybean plants from seed to seed in space using purifier that completely destroys airborne bacteria,
the ADVASC payload—an autonomously operated mold, fungi, mycotoxins, viruses, volatile organic
plant growth unit. The ability to grow plants from compounds such as ethylene, and odors. The device
seeds through several generations has proven to has no filters that need changing and produces no
be challenging in space and is critical in developing harmful by-products, such as the ozone created by
hardware and operational concepts to take human some filtration systems.
explorers farther beyond low-Earth orbit. Food preservation customers include supermarkets,
While serving as a unique plant-growth chamber, produce distribution facilities, food processing plants,
the ADVASC hardware design has also contributed wineries, distilleries, restaurants and large floral shops.
Reeves Floral, an Airocide user, reported 92% reduction
in airborne mold and a 58% drop in airborne bacteria
levels after only 24 hours of operation in its floral
storage warehouse. These units in walk-in coolers
can preserve freshness of produce during storage and
In addition to eliminating virtually transport, increase safety in food preparation areas, kill
all known airborne germs bacterial contaminants in flowers, and protect against
and diseases, the technology spoilage and contaminants.
reduces the burden on high- Units also have been deployed to India and the Gulf
Cooperation Council, which includes the countries of
efficiency particulate air filters Bahrain, Kuwait, Qatar, Oman, Saudi Arabia, and the
and laminar flow environments. United Arab Emirates. In these areas, where refrigerated
trucks carry groceries from rural farmland to towns
miles away, the unit preserves freshness and prevents
food spoilage.

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