Algae experimentation in space: scientists will study how algae could be used as the foundation for future food or feedstock for things like paper or plastics in space. Credit: Melissa Holmes, Rocky Mountain College

Amy Thompson writes in Space.com that SpaceX successfully launched its 15th Space Station cargo-resupply mission on Friday, June 29; carrying a payload of experiments designed to better understand how astronauts can have access to fresh foods and grow their own in space.

This mission — dubbed VEG-03G, H, I (aka Veggie) — is a partnership between NASA and Fairchild Tropical Botanic Garden. Students helped choose the plants bound for Veggie, as this payload is also designed to engage youngsters in STEM (science, technology, engineering and math) disciplines.

To date, most of the crops cultivated in the Space Station’s specialized growth chamber have been a variety of lettuce dubbed “Outredgeous” red romaine. But that’s about to change. Tucked inside the Dragon were four new types of plants: “Dragoon” lettuce, “Extra Dwarf” pak choy, “Red Russian” kale and “Wasabi” mustard will join a new crop of the tried-and-true red romaine. In total, there will be 18 plant pillows added to the veggie chamber from this arrival.

A batch of space algae has also arrived at the orbiting lab. Mark Settles, a researcher at the University of Florida, and his colleagues, are hoping this investigation will help them understand how the algae responds to microgravity, as well as identify the genes associated with more-rapid growth. The researchers hope this will allow them to engineer the algae for mass production in space.

Algae are incredibly efficient at using low-intensity light conditions to make energy via photosynthesis, which makes the plant perfect for on-orbit growing, the researchers said. Algae are also useful as a bio-based feedstock (meaning the plant can be used in the manufacture of materials such as plastic and paper).

Environmental stresses (like microgravity) have been known to spur epigenetic changes in the algae. These can sometimes produce extremely useful compounds, such as antioxidants, and even substances that can be used to help mitigate radiation. The team will study and analyze the strains to see which types of algae respond best to microgravity, as there haven’t been many studies.

There’s one major concern, however: the algae’s growth. Dr. Settles said the biggest issue with growing algae in space is that most algae species grow fastest in liquid, but liquids don’t behave the same way in space as they do on the ground. “We’re trying to domesticate algae for growth systems that would be practical in space,” he said.

As part of the investigation, and search for algae growth genes, the crew will attempt to grow several strains of algae inside porous plastic bags within the Veggie chamber. “We will basically be testing breathable plastic bags that are used to grow animal cells in culture on Earth and will grow the algae in those bags,” Dr. Settles said. “Laboratory algae have grown in glass flasks, (placed) on shakers for more than 50 years. In plastic bags, they grow a lot slower than they do in a flask.”

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