The effects of cosmic radiation and UV radiation on the survival and growth of microalgae are being investigated by scientists from the Faculty of Agriculture of the Mendel University in Brno. Last year, experts sent a probe into the stratosphere carrying several dozen samples of these microorganisms. The first results now show that the stay in space had a long-term effect on the algae. In the future, scientists would like to use the new findings to select resistant species that astronauts could use, for example, to produce biofuel or to purify water.

“The great thing about microalgae is that they have multiple uses. People are familiar with chlorella, for example, which is used as a dietary supplement and contains proteins, vitamins, antioxidants, B12 and other beneficial things. But there are many more possibilities in space,” said Katarína Molnárová from the Space Agri Technologies Laboratory at Faculty Agriculture of the MENDELU.

Among the benefits of algae is that they produce oxygen, and some can also be the basis of biofuel production or an aid in water purification. “I would also like to work on breaking down toxic substances using microalgae. For example, the soil on Mars contains large amounts of perchlorates, which are toxic salts that cause thyroid disorders. When grown on such soil, salts get into the plant’s body, and for astronauts the consumption of these crops would represent a significant health risk,” explains Molnárová. However, according to the scientist, it would theoretically be possible to break down perchlorates with the help of microalgae. “Of course, we must not forget the use of microalgae as classic food supplements,” she supplied.

In an experimental flight last fall, scientists sent around 70 samples of various microalgae into the stratosphere. The probe remained at an altitude of 35 kilometers for about an hour. Microalgae were affected by cosmic radiation, UV radiation, but also by temperature changes. “Roughly 5 percent of the samples did not survive the journey into space, which we consider a good result,” said the scientist.

In the laboratory, the scientists then cultured some of the surviving microalgae and froze some for further analysis. After two weeks of cultivation, spectral analysis was performed. “We found that even after those two weeks there was repeated antioxidant activity, which means that the samples were still recovering. Even such a short exposure to space conditions was able to mark the microalgae for several generations,” pointed out Molnárová. Currently, the experts plan to focus on molecular studies and RNA isolation.

At the same time, the scientists are already planning further research that could follow up on the new findings. “Basically, there are two ways. These researches would then have a real, practical use not only in space,” assesses Molnárová. The first option is to create a kind of catalog of microalgae that would summarize how different species respond to space conditions. “We would describe that, for example, this species produces large amounts of lipids in space, so we will use it to make biofuel. Another produces a strong antioxidant, so it will be a suitable supplement to the diet of astronauts,” added the scientist.

The second of the ways is based on the description of gene expression. In the future, experts would like to use genetic engineering and, in quotes, breed the perfect space algae. “Once we know what a certain gene is, we can edit it so that the space algae, for example, produces even more lipids, antioxidants and so on,” said Molnárová.

Scientists would also like to participate in further flights of stratospheric balloons as well as longer space flights with samples staying in orbit.

For more information contact Mgr. Katarína Molnárová, katarina.molnarova@mendelu.cz, +421 944 304 866, Space Agri Technologies Laboratory, Institute of Chemistry and Biochemistry of AF MENDELU.