In the new study, astronauts will see if bacteria that produce sugar can be used to create a food source for astronauts in low-or-zero-gravity situations. One reason for trying, Gizmodo reports, is because “space food” experiments to date have focused on growing plants, such as lettuce. While green vegetative matter will provide some important nutrients, the quantities that can be grown will not provide space travelers with a sufficient number of calories.
The study is set to begin in 2017. At some point, a German-designed satellite will, according to New Scientist magazine, be blasted into space. The payload will contain genetically modified bacteria. The bacteria are trademarked “PowerCell.” The bacteria are from the genus Anabaena and the study is being co-ordinated by NASA’s Ames Research Center.
Anabaena are cyanobacteria (what are sometimes mistakenly called “algae”.) The bacteria consume plankton and are found in association with many plants, like mosquito fern (Azolla.) An example species is Anabaena variabilis.
While most cyanobacteria are what are termed photoautotrophs (dependent on sunlight for energy), a few can take up and use sugars either only in the light, or in the dark. Through using light, Anabaena are capable of photosynthesis, which creates sugar (fructose) from carbon dioxide, water and sunlight. A small quantity of sugar is excreted from each bacterium during the process. Scientists think this can be captured and use as the basis of a food source. The genetic manipulation of the organism is designed to lead to a higher output of sugar than the “natural” form of the bacterium is capable of.
While studies on Earth suggest the experiment will be successful, the effects of different gravitational pulls, as found onboard the ISS, could alter the biochemical synthesis, rendering the sugar production unsuccessful or too inefficient to be worthwhile.
In order to assess the quantity of sugar produced during the six-month trial, the research team has also engineered the bacterium Bacillus subtilis to turn those sugars into a red pigment. This will allow the sugar production to be quantified, through sensors detecting the degree of color change.
Moving down an alternative route, scientists based at the Queensland University of Technology have found a gene in the native Australian tobacco plant Nicotiana benthamiana (commonly called Pitjuri.) This is of interest because the plant is very hardy and can survive prolonged periods of drought. Locating the gene could aid with genetically engineering plants to grow in space or even on barren planets like Mars. The latter could lead to something similar to the vegetable growing antics of Matt Damon’s character in the movie The Martian.
The Australian study is published in the journal Nature Plants. The article is titled: “The extremophile Nicotiana benthamiana has traded viral defence for early vigour.”
Other “space food” initiatives include seeing whether 3D printing can be used to produce pizzas and pharmaceutical drugs, in addition to tools. These additive manufacturing processes remain at an early stage, although results are promising. With pharmaceuticals, Digital Journal reported earlier this year about the top medications required by astronauts being sleeping pills and skin ointments (in fact, not very different to the first aid bag packed by airline pilots).
In current practice, U.S. astronauts aboard ISS are encouraged by their government to drink “water” produced from their own urine. Russian cosmonauts, however, refuse to drink recycled urine. The pee from the Russian team doesn’t go to water, however; The Guardian reports that U.S. astronauts willingly drink it.
