Breathe modestly: microalgae will provide oxygen to humans on flights to the Moon and Mars

In Moscow, for the first time, the work of a Russian bioreactor in which oxygen is synthesized by microalgae was publicly demonstrated. The developers believe that in the future such systems can become part of life support complexes for long-term space expeditions, including flights to the Moon and Mars. Despite the fact that research in the field of bioregenerative respiratory systems has been conducted since the 1960s, it is only now that it has been possible to create an installation that ensures comfortable human breathing for a long time. After the presentation, the Izvestia correspondent personally tested the development and assessed how convenient it is to use such a respiratory system.

Deep space air

Russian scientist Alexander Shayenko and the 435nm project team have developed a prototype photobioreactor in which microalgae absorb carbon dioxide and release oxygen through photosynthesis. Such a system makes it possible to form an almost closed air exchange cycle.

During the tests, the specialists continuously monitored four key indicators: blood oxygen saturation, pulse rate, as well as the concentration of oxygen and carbon dioxide in the inhaled gas mixture.

— We have already conducted an experiment lasting 45 minutes, although 15 minutes would be enough for verification. This margin allowed us to make sure that the system is working steadily. About ten minutes after the start of work, the oxygen and carbon dioxide content reaches a stable level and then practically does not change," said Alexander Shayenko, the author of the project.

The development was created as one of the elements of a future biological life support system for long-term space expeditions. The authors of the project took Soviet photobioreactors from the 1960s and 1980s as a basis, but completely rethought their design.

— We took the key idea of the Soviet Lilac plant: microalgae are grown in a very thin layer, so that the entire crop volume receives uniform illumination. However, this idea has already been implemented on a modern technological basis. LEDs were used instead of xenon lamps, and all the processes of the photobioreactor were fully automated. As a result, energy consumption was reduced by about 30 times compared to Soviet technology," the scientist explained.

During the experiment, the installation operated in a cumulative mode, however, according to scientists, for continuous operation it can also be started in a continuous mode.

On Earth, such photobioreactors are already used for the production of biologically active additives, feed for farm animals and aquaculture, as well as for wastewater and air treatment. According to scientists, research in the field of bioregenerative respiratory systems has been conducted since the 1960s. However, it has only now been possible to create an installation capable of providing a person with comfortable breathing for a long time.

Will the prototype of the breathing system come to implementation

After completing the official presentation, the Izvestia correspondent personally tested the installation. A sealed mask connected by hoses to a photobioreactor is put on the face. The first breaths seem unusual: the air is noticeably warmer than usual, and the mask itself creates little resistance when breathing. However, after a few minutes, these feelings practically disappear.

The smell of the air was unexpected. It has light herbaceous and algae notes, reminiscent of a fresh sea breeze. At the same time, there is no chemical taste, a feeling of lack of oxygen, shortness of breath or other signs of discomfort. As Alexander Shayenko noted, in ten years of working with the technology, he has never encountered symptoms of hypoxia when using the installation.

During the experiment, it was possible to talk freely, and the body's indicators remained within the normal range. Subjectively, breathing felt like being in a mountainous area, where the air felt fresher and richer. However, the author of the project emphasized that this is only a conditional comparison: during the operation of the system, not only the human body gradually adapts, but also the culture of microalgae itself.

So far, we are only talking about demonstrating technological capabilities. Prior to the practical application of such systems in manned space exploration, a long stage of testing, technology development and miniaturization of equipment will have to be completed.

As noted by technology expert Sergey Pomortsev, the concept itself looks promising from an engineering point of view. However, many technical questions have to be answered before such systems can be put into practice.

— This is an ordinary technology demonstrator, not a ready-made solution. Space-based life support systems must operate for months or even years without serious maintenance, withstand the failure of individual components, and take up minimal space. At the moment, the installation shown proves that the principle itself works, but there are still a huge number of engineering tasks to be solved before real use in space or mass application on Earth. In its current form, such an installation is not like a spacesuit, but you can't even put it on a ship," Sergey Pomortsev pointed out.

Despite this, the developers intend to continue the project. Research has been underway for about ten years, and the next stage will be the introduction of microfluidics technologies, which control microscopic fluid flows. According to the authors, this will make photobioreactors more compact, energy efficient and technologically advanced, bringing them closer to use as part of promising bioregenerative life support systems for space expeditions.

In addition, the team of scientists is considering the possibility of cooperation with schools and universities in the field of supplying them with educational photobioreactors for practical study of high-intensity cultivation of microalgae.