Birgit Mitter

Home
Discover
Impact Stories
Birgit Mitter

For many years, Birgit Mitter has investigated microorganisms living in plants. She and her colleagues active in this field of basic research have developed a machine that places microorganisms in plant seeds in a controlled manner. This technology harbors great potential for industrial use and eventually became the foundation of the spin-off Ensemo. It offers a way to support crop plants that does not rely on chemical or environmentally harmful fertilizers or pesticides.

Strictly speaking, an animal or human is never alone. Living beings are populated by many billions of microorganisms, which live both in and on these bodies. As is demonstrated by the gut microbiome, such microorganisms can play vital roles. And they also do so for plants. Most endophytes, as these microorganisms that populate plants are called, hardly affect their hosts. The few that do, however, don’t hold back. They bind nitrogen from the air or release phosphate that was stored in the soil so that it becomes available to plants again. Some microorganisms protect their hosts from disease. And where tomatoes or strawberries are concerned, their taste changes according to the single-cell organisms that live on them.

Endophytes have been Birgit Mitter’s specialty for a long time. The microbiologist worked for the AIT Austrian Institute of Technology for many years, engaging in molecular-biological analyses of microorganisms in and on plants in numerous projects. In the course of this research, which included two projects funded by the Austrian Science Fund (FWF), Mitter and her colleagues found themselves looking for ways to introduce bacteria to seeds in an efficient way in order to be able to then look into the interactions between the plants and the microbiome. Managing to do exactly that eventually led to the spin-off Ensemo, based in Tulln in Lower Austria, which Mitter co-heads with her former AIT colleague Nikolaus Pfaffenbichler.

Ensemo provided a stage to develop a technology invented as part of basic research up to the point where it was ready to be marketed: a machine that rapidly injects microorganisms into many thousands of plant seeds is also the key to supporting crop plants in a controlled way without having to rely on chemical means that potentially harm the environment. The targeted use of the interaction between microbiome and plants could potentially simplify organic agriculture, making a sustainable way of cultivating fields more competitive.

Reducing fertilizers and pesticides for economic reasons

The first products have already been launched. They include soy seeds enriched with rhizobia, which are bacteria that fix nitrogen from the air and make it available to the plants. “As a result, there’s almost no need for additional nitrogen-based fertilizers,” Mitter says. “In general, being able to save on fertilizer and pesticide, huge amounts of which are spread across our fields today, turned out to be a strong economic argument in favor of our technology.” Ensemo staff are already testing further microorganisms, for instance ones that mobilize phosphorus, as well as hormone-like substances that could potentially increase plant resilience.

In a nutshell

In a project investigating the role of microorganisms in plants that was funded by the Austrian Science Fund (FWF), Birgit Mitter and her team faced the methodological question of how to introduce bacteria into seeds in a controlled manner. The technology they ended up developing fixates every single seed before cutting it open and injecting microorganisms. Once this has been completed, the seeds are closed again. This approach has also proved promising for producing new kinds of seeds that hardly need any fertilizer or pesticide thanks to the introduced bacteria. The technology could make a major contribution to creating crops that are more resilient and richer in nutrients in the future. Following the market introduction of the technology for corn seeds, the first soy seeds treated by Ensemo were planted in Austria and Germany in 2025, producing a rich harvest. The long-term potential of this approach is especially relevant for countries in the Global South, where crops need to be particularly resistant to withstand the effects of climate change.

Portrait Birgit Mitter — Microbiologist Birgit Mitter has explored how microorganisms and plants interact in numerous research projects. To carry out her analyses, she had to find a way to efficiently introduce bacteria to seeds. The solution she came up with inadvertently turned into the founding idea for the start-up company Ensemo. © Andrea Aichhorn

Close-up of a machine for insertion — Cutting down on fertilizers and pesticides – the result is a machine that introduces microorganisms to seeds at an enormous pace. © Matthias Obergruber

“Being able to save on fertilizer and pesticides turned out to be a strong economic argument in favor of our technology.”

The technology could be put to use in many more applications: the targeted introduction of microorganisms could make plants more resilient against heat and drought and improve their intake of nutrients. They could help fend off pests, helping their hosts weather this stress more easily. Theoretically, the right mix could even impact nutrient content and flavor, which, however, is a field that still needs a lot of research. To tap this potential more effectively, Ensemo is currently looking for partners: “We are not champions at developing microorganisms; our expertise lies in the technology that introduces them to seeds in a targeted way,” Mitter emphasizes. “We cooperate with companies that use these tools to get their own biological active agents out to agricultural fields.”

Researching microbes in African trees and stressed plants

Mitter has researched a great variety of aspects related to endophytes in the course of her career, for example looking into their effect on the active ingredients of the pepper bark tree, which is used as an herbal remedy for respiratory diseases and infections in Kenya and Uganda. Through a project funded by the Austrian Science Fund (FWF), the researcher was able to show that there are, at a minimum, correlations between the microorganisms and the ingredients – which often differ from tree to tree – that stimulate the immune system. A further research project, which was also financed by the FWF, built on the insights gained to explore how a plant’s signals can influence the microorganisms populating it. “We wanted to take a look at the other side: instead of looking at how the plant reacts to endophytes, this project was about learning how bacteria adapt to changed conditions in the plant – for instance when it’s subjected to a great deal of stress – through their gene expression,” Mitter explains.

The researchers were able to show that the microbes’ reactions to plant signals are surprisingly strong. And this was not the only outcome of this project. Mitter and her colleagues had to settle the fundamental methodological question of how the bacteria whose reactions they wanted to research could be introduced to the plants. One way would be to spray the microorganisms on the petals to make them part of the next generation’s seeds, which is how nature itself does it in many cases. “This method worked fine in lab conditions, but it was hard to control in the setting of open-air fields,” Mitter explains. “So we had to find a different solution. In the end, we came up with an idea for a machine that would prepare every seed exactly the way we needed it.”

Short bio

Birgit Mitter studied Microbiology at the University of Graz. She wrote her doctoral thesis at the Graz University of Technology while simultaneously working at Seibersdorf research centre, today’s AIT Austrian Institute of Technology. Already during her doctoral research, Mitter completed a molecular analysis of endophytes. She then remained at the Graz University of Technology to research enzymatic reactions before transferring back to AIT to dive further into her favorite topic of endophytes. From 2007 to 2011, she worked on the “Microbial endophytes from the pepper bark tree” project, which was funded by the FWF. In a further FWF-funded research project, she looked at “ECF sigma factors: How endophytes sense the plant”. After developing a technology that enables the controlled introduction of microorganisms in plant seeds at AIT, she founded the spin-off Ensemo together with Nikolaus Pfaffenbichler in 2021 and perfected the technology to bring it to market.

Close-up of processed seeds with small slits — The technology enables a throughput of 3,000 seeds per second. © Matthias Obergruber

“Massive engineering challenge”

The machine used at Ensemo today can treat 3,000 seeds per second. The fully automated machine is controlled by software that guides seeds into a ring full of tiny pins. Using gentle pressure, every single one affixes one seed each. Then a miniature saw is extended and carries out a small cut – in a careful and controlled way to keep the embryo in the seed intact. Next, a liquid containing the desired microorganisms is injected; a process that is also done gently and without undue pressure. Finally, the opening is closed with a natural polymer and the seeds are quickly dried. “Developing the engineering behind this machine was a huge accomplishment because this procedure requires a high level of precision and serious speed in order to be able to prepare the amounts needed by the seeds industry,” Mitter says.

“Developing the engineering behind this machine was a huge accomplishment because this procedure requires a high level of precision and serious speed in order to be able to prepare the amounts needed by the seeds industry.”

When she started working on the machine’s design, back at the AIT, she had no idea that this would one day lead to a start-up. “While we were doing the research, founding a company was never on our minds. When the method turned out to work and a patent was granted for it, we first considered a licensing model to make the invention available to the seeds industry,” the researcher recounts. “We received positive feedback from the industry, but the large seeds companies are not set up to quickly commercialize developments of this kind.” In the end, AIT leaders suggested to Birgit Mitter and her colleague Nikolaus Pfaffenbichler to further develop the technology to make it ready for the market in the framework of their own spin-off. In 2021, they founded their company. Today, they have nine employees.

Birgit Mitter and her team in front of a modern wooden facade — Today, nine staff members work for the company founded in 2021. From left to right: Marija Gumze, Hanna Wolf, Nikolaus Pfaffenbichler, Birgit Mitter, Doris Gusenbauer, Nicolas Gerstenmayer, Lisa-Maria Ohler. Evangelos Kyrilas and Gregor Wolfsgruber, who joined Ensemo in the fall of 2024, are not in the picture. © Matthias Obergruber

“While we were doing the research, founding a company was never on our minds.”

So far, Ensemo has focused on soy and corn. Wheat seeds, which are much more delicate, would require an even higher degree of precision and throughput, which makes further development work necessary. Ensemo does not sell its machines but currently operates them at the locations of clients who want their soy seeds prepared. “In 2025, together with our internationally active partner Saatbau Linz, we covered about 3.5 percent of soy seeds in Austria and Germany,” Mitter says, not without pride. “And we got very positive feedback.”

“In 2025, together with our internationally active partner Saatbau Linz, we covered about 3.5 percent of soy seeds in Austria and Germany.”

Even though Ensemo’s first customers hailed from Austria and Europe, the company has its eyes on the global market in the long run – including cultivation areas in the Global South, which depend on resilient types of seeds that are easy to use due the effects of climate change and the high cost of fertilizers and pesticides. “We’ll take the first step in that direction in spring of 2026,” Mitter says. “That’s when we’ll send a machine to Brazil and test it at a customer’s facility.” If the Tulln-based company manages to realize the seed revolution it’s after, soy and corn cultivation could soon be much more sustainable than in the past.