25 August, 2017
Researchers are studying how to repurpose these molecules and convert them into products the astronauts need, such as polyesters and nutrients.
While anyone who has seen The Martian knew that this was coming sooner or later, the work of Blenner's team focuses on recycling astronaut's human waste to help them make the trip to the Red Planet in the first place. He further said that "Atom economy will become really important". Assuming you have the vehicle, fuel, correct environment, and oxygen required, you still need to make sure that your human passengers are fed, have access to water, and have the tools necessary to complete whatever tasks they are issued. "Having a biological system that astronauts can awaken from a dormant state to start producing what they need, when they need it, is the motivation for our project", he says.
Blenners' team are now working on a biological system which includes strains of the yeast Yarrowia lipolytica, which requires both nitrogen and carbon to grow. The microbes can use the nitrogen in human urine and carbon dioxide from their breath to create useful compounds. And the team of Blenner's found that the yeast can get their nitrogen from urea in untreated urine. But to use CO2, the yeast require a middleman to "fix" the carbon into a form they can ingest. Blenner has used the yeast strain, a close relative of baker's yeast available in grocery stores, as a template that he then modifies with genes from algae and phytoplankton.
And the positive thing about the yeast strains is that it produces omega-3 fatty acids, which give to heart, eye, and brain health. But in the meantime there are several more terrestrial applications they can explore, such as producing omega-3 supplements for fish farms and making other speciality chemicals. One strain of engineered yeast creates polyester polymers that could be used in 3D printers to create needed tools or parts for a long space mission. And the team of the Blenner is busy to use this yeast strain to generate different monomers that can be polymerized into different types of polyesters with the different variety of properties.
Of course, the research is preliminary and the researchers note actual output of the yeast and other ingredients is pretty small - but that's what the scientists hope to improve with time. "We're learning that Y. lipolytica is quite a bit different than other yeast in their genetics and biochemical nature", Blenner says. To ask questions online, sign in with a Google account. Its main offices are in Washington, D.C., and Columbus, Ohio.
