Nature as a model for inventing

Berlin-based SUSFERT partner ABiTEP talks about biological strain development, inventing fertilisers & EU fertiliser regulation.

UN and EU agendas promote research that include developing microbial strains that facilitate plant health and better crop yields. Resilient plants that perform under unfavourable conditions require intelligent solutions working with nature. SUSFERT uses Bacillus micro-organisms derived from the natural world. Photo Elisa Schwarz.

Today on 12 May, 2022, the United Nations International Day of Plant Health creates awareness about the role plants play in sustainable food production to meet Zero Hunger targets, outlined in the UN Sustainable Development Goals. Part of this campaign is to also “promote investment in plant health innovations, research, capacity development and outreach”.

On SUSFERT, scientists from the Berlin-based company, ABiTEP GmbH, now part of the Andermatt Group, are searching for plant growth promoting and nutrient mobilising micro-organisms. ABiTEP microbial strain development has identified several Bacillus species, derived from nature, that are currently creating new fertilisers.

Microbes from the natural world

How exactly do scientists extract microbes from the natural world that will create sustainable solutions without gene modification for better plant health?

More importantly, where do they find these microbial strains? Can scientists access strains from strain banks, say under the 1980 Budapest Treaty that deals with micro-organism patent procedures?

Does ABiTEP have its own strains?

And, what about the rules and legal framework of the 2014 Nagoya Protocol on the accessing of, and sharing of genetic resources?

Another essential aspect to future biological solutions for better plant health is whether the new European fertiliser regulation EU.Reg. 2019/1009 (due to come into force on 16 July, 2022) will support microbiological development. Inflexible regulation can hamper innovation efforts.

Effective regulation should reflect reality

While biologicals from nature for plant protection undergo the same strict regulatory hurdles as their chemical counterparts, ABiTEP is of the opinion that the use of beneficial microbes from the natural world are more environmentally friendly and sustainable. When the microbes are returned to nature in a product, they will perform their natural function there because they have done so before. There will be no interference with the natural system, as is expected from chemical pesticides, or genetically engineered plants. Photo courtesy of ABiTEP.

If we were to leapfrog chemical-synthetic products in favour of biological solutions that are estimated to create less potential harm to our natural world, perhaps the new regulatory category of bio-stimulants within the new regulation should be expanded to reflect what is safely/readily available.

ABiTEP Head of Regulatory Affairs, and biological patent inventor, Dr. Kristin Dietel, and ABiTEP Head of Research and Development, Elisa Schwarz, take that view. They think that there should be more than just four different species registered on the bio-stimulant registration list, which is the case so far. This would better reflect what is safely available in Europe.

Maybe the product registration processes for bio-stimulants should be simplified. But this would mean that European countries would need to agree on the use and regulation of micro-organisms. Currently, both national and European law can be followed.

According to Dr. Dietel, Germany takes the attitude that if the micro-organism passes government health and safety rules, as well as the technical and associated rules pertaining to biological agents, then the manufacturer takes the development risk. In essence, they see the risk as being minimal. France, on the other hand, takes the view that every micro-organism is dangerous until proven otherwise, which results in costly scientific studies being replicated, to what end?

But before the ABiTEP scientists take you through strain development, we briefly look at the mammoth task that scientists face every day in screening bacteria and other micro-organisms to develop biological solutions for better plant health. These innovations make plants more resilient to pests and diseases, and produce better crop yields, even under unfavourable conditions.

Finding Mr. or Ms. Right in nonillions

It is estimated that 50 000 000 000 000 000 000 000 000 000 000 bacteria live on earth.

Bacterial colonies grow on solid media. Photo courtesy ABiTEP.

How can we even name such a number, let alone find the right match to isolate the ideal strain for biological solutions, such as the bacillus species that are used on SUSFERT?

Well, the first answer is definitive. That many zeros after a five is officially called fifty nonillion, not that any of us will ever use that word.

To answer the second question is a little trickier. Finding Mr. or Ms. Right in these nonillions of micro-organisms to isolate for a particular purpose involves a little help from a strain bank. It’s a bit like screening millions of partners on a dating app.

The micro-organism strain, like the person, must have the right attributes; be attractive enough to fix a date; sustain the scale-up of romance (or not); and finally, even perform compatibility tests that hopefully will lead to a stable, non-toxic relationship that has a long shelf-life.

We all know that when the right formula is discovered, and most screening conditions are met, the courtship can span years before any marriage or longstanding partnership is cemented. Also, once the relationship has endured a few rigorous tests, it needs the help of good governance in the form of easy legal access to cement the partnership. The same goes for strain development.

Finding the right micro-organism can take up to 10 years until the product is ready for market. That is a lot of time, investment, commitment, and even perseverance that deserves a well-defined, accessible pathway to actualisation. But do we credit scientists for their creativity. Their tirelessness. Their tenacity to break through after many tries?

SUSFERT does! That is why Communications asked Dietel and Schwarz to take us into their world of strain development. The ABiTEP scientists also address important issues affecting the regulation of micro-organisms that will be a part of the future, sustainable fertiliser story.

What does ABiTEP do?

Close-up of bacterial (Bacillus) colony on solid media. Picture courtesy of ABiTEP taken via microscope.

ABiTEP GmbH develops and distributes biological alternatives to conventional chemical-synthetic pesticides, pest control, fertilisers and feed additives. For this we produce beneficial micro-organisms in liquid fermentation in modern bioreactors with subsequent concentration and processing. Through using the latest technology and our know-how, we create tailor-made solutions for our project partners of SUSFERT.

ABiTEP strain bank

The overall development process for such a product usually starts with a screening of our micro-organism strain bank. On SUSFERT, we looked for candidates with target properties needed for a fertiliser product such as phosphate mobilisation or iron supply. Then we prepare them for testing so that our project partners can combine them with waste materials to create something new and sustainable which will bring us closer to the goals of the European circular economy.

The ABiTEP strain bank contains more than one thousand strains that we built up over more than 20 years of scientific work. We have specifically found micro-organisms that have a huge variety of beneficial properties suitable for one, or another field of application.

Global strain treaties

In most countries worldwide strain banks exist. They are owned by universities, institutes, private companies, and others. Then there are public strain banks for deposit under the Budapest Treaty for purposes of patent procedure existing, but commercial use of these strains is restricted to the patent holder and for scientific purposes.

Usually, strains are accessed through isolation from environmental samples by institutes or companies considering the rules of the Nagoya Protocol. From this starting point of isolation, it is then a long way until you have a ready to use product with the desired properties.

In the case where you don’t have an existing strain in a strain bank that is suitable for your envisaged solution, you have to start from scratch.

Critical parts of strain development

Sporulating Bacillus cells (rod-shaped) in liquid media; the small refractive cell compartments in the centre of the rods (the white bubbles) are forms of prespores. Picture courtesy of ABiTEP taken via microscope.

It is estimated that 5E+31 bacteria live on earth. 5E+31 means the number five with 31 zeros behind it which is an incredibly large number. This is the 50 nonillion that was mentioned in the introduction.

To find the Mr. or Ms. Right under these circumstances is very challenging. There are different, critical parts in this process.

First, you think about the function of the micro-organism you need.

Second, you think about the conditions under which, or where it may be found.

Third, you take different samples from suitable environments, like soil for example, and then you try to isolate micro-organisms out of those.

Assuming you use a soil sample, usually there are around 10 billion bacterial cells in one gram of soil. From this you will be able to cultivate one per cent, which gives you 10 million candidates left for screening.

Finding the ideal match from millions

So, you see that the screening of these immense numbers of candidates is the most important step, and the first big hurdle, in the process.

You have to be really confident regarding your methods in being able to find the needle in the haystack.

After screening you need to show that the candidate is:

Non-toxic to humans, animals and the environment.

Economic to produce.

Effective for the purpose you have specifically isolated it for.

Registered under the respective legislation.

In summary, it is an extremely expensive, time-consuming process that usually takes more than 10 years until you have a product ready for market.

Back to the lab — the strain is identified

The mini fermentation system sits parallel to the mini bioreactors (250ml volume) which is the first scale-up step after a shaking flask. Picture courtesy of ABiTEP.

Yes, once we have identified the fitting microbe in our microbiology laboratory using different selective techniques, the bacterial isolates with the best performance are selected for subsequent process development.

For this purpose, growth assays are used to identify the most suitable composition of nutrients that offer the best conditions under which the bacteria can thrive. In addition, the specific pH and temperature range, as well as the oxygen demand of the bacterial strains, are determined to further optimise the growth conditions to generate as much biomass as possible, over a short period of time.

Scale-up process

In the next development step, these parameters will be transferred to a larger laboratory production scale using a bioreactor. There are many sizes of bioreactors where the scale-up process is validated.

15 litre bioreactor. Photo courtesy of ABiTEP.

Here the adaptation and optimisation in terms of yield and real biotechnological production processes start. After this, we scale up the process in different steps.

In the last phase, either a 5,000 litre bioreactor is used, or a 7,200 litre one that is pictured below. Picture courtesy ABiTEP.

This allows us to adjust all parameters that are important for an economic production including downstream processes like concentration and formulation.

Inside the stirrer of the bioreactor. Picture courtesy ABiTEP.

So, first prototype products are produced that were provided for in vivo and in vitro experiments (for example, pot and plant trials). These prototypes can also be used to perform technical compatibility tests with the production plants of the final fertiliser granules of our project partners and for the first product stability tests (shelf life).


The inspection glass in the lid of the bioreactor allows the scientists to observe the fermentation process taking place inside. Picture courtesy ABiTEP.

After validation in the small pilot scale phase (70 litres), the production process phase then has to take place in small (600 litres), or large (7,200 litres) production scale bioreactors.

Top of the 7,200 litre bioreactor. The first picture in this series shows the 7,200 litre bioreactor in its totality i.e. what is contained underneath the floor.

For this scale of enlargement, the downstream processing function also needs to be adjusted to the technical equipment.

Natural microbes over genetic engineering

In our opinion, the use of beneficial microbes is environmentally friendly and sustainable. We work exclusively with non-genetically modified micro-organisms that are isolated from nature.

When we put them back into the environment, they will perform their natural function there because they have done so before. There will be no interference with the natural system, as is expected from chemical pesticides or genetically engineered plants.

For SUSFERT, we have selected bacterial strains that have proven abilities to colonise plant roots to help the plant grow healthier and produce a better yield, even under unfavourable conditions.

These natural bacterial strains have been demonstrated in the project. They can supply nutrients, such as phosphorus or iron, to the plant from sources that are not available to the plant normally. More SUSFERT blogs can be read on this topic HERE and HERE, as well as SUSFERT’s Green Chemistry scientific paper.

High interest from agricultural sector

SUSFERT Spring 2022 fertiliser field trials are currently in the ground with maize crops across several EU countries. Photo courtesy of Elisa Schwarz.

The interest in micro-organisms is huge from the agricultural sector and has grown over the years because of legislative restrictions in the use of chemical pesticides and fertilisers.

Today, farmers know about micro-organisms, so they play an increased role in the agricultural production process. Different species of lactic acid and other bacteria are used as starters for silage production, feed additives and to improve the efficiency of biogas production.

Big hurdles to market launch

Finding solutions in the era of climate change to crop yield enhancement through better plant nutrient uptake will dominate intergovernmental and global initiatives. Photo courtesy of Elisa Schwarz.

Fungi and bacteria are known for their plant protection potential and for their ability to improve the nutrient availability and stress tolerance for plants. The biggest concern for products, on the basis of micro-organisms, are the high legislative hurdles for market launch.

Biologicals for plant protection have to face the same long-lasting and expensive registration process as their chemical competitors, with the same strict requirements.

Micro-organisms used in fertilisers have to adhere to the national fertiliser legislation in every country with very different requirements ranging from a very strict and expensive registration process, for example in France, to a very easy market launch in Germany or Austria.

Restrictive legislative measures

With the new REG EU 2019/1009 fertiliser legislation the product registration for micro-organisms will be harmonised. Under the new legislation a new category was established — plant bio-stimulants.

At the moment, both national and EU legislation apply in the field of fertilisers. At present, micro-organism products can be registered under both national legislation, i.e. the National Fertilizer Law, and the new European Fertilizer Regulation REG EU 2019/1009.

However, it is expected that countries will implement the EU Fertilizer Regulation in their legislation over time.

But only four different species are on the list for registration, which does not reflect the variety of micro-organisms available as fertiliser on the market currently.

Products that are currently on the market have shown their efficacy in plant growth promotion. They also belong to a species that is known for its safety. They automatically could be included on the positive list for public use under the plant bio-stimulant category within the fertiliser regulation.

Work involving micro-organisms even now is regulated under existing occupational health and safety guidelines and legislation. There are technical rules for biological agents currently in place which assess the risk posed by a micro-organism to human and plant health. These existing procedures and frameworks could be used to save time-consuming and costly studies that prove the same thing again and again, which is limiting.

Furthermore, checks and controls are carried out by the European Food Safety Authority (EFSA), the agency of the European Union (EU) that provides independent scientific advice and communicates on existing and emerging risks associated within the food chain. They safeguard the list of already known, tested non-hazardous biological species. So, the knowledge concerning safe species, and non-safe species, is already known. It would just need to be used and implemented for the EU Reg. 2019/1009.

So, you see the demand for biological solutions is high, but the way to make them available to the farmer is quite complicated and long.

Converging viewpoints within the EU

I think that the biggest problem is the different views held and expressed concerning micro-organisms within the different member countries of the EU.

As previously mentioned, there are many countries that have a positive attitude towards micro-organisms, such as Germany, Austria, the United Kingdom, Ireland, Finland and the Netherlands (presently).

In Germany, where we are based, it is sometimes not even necessary to register micro-organism products in a long procedure, but the manufacturer can put the products on the market at his or her own risk.

Then again, there are countries, like France, that have very high hurdles for placing micro-organism products on the market. There, expensive studies have to be carried out to prove the harmlessness of the respective micro-organism. Every micro-organism is considered dangerous until the opposite is proven.

ABiTEP’s stamp of approval

In our work we take nature as a model for our inventions and try to translate them into practical solutions for different areas of use. Our research is dedicated to develop products based on biological processes to be able to offer solutions for the most diverse areas in agriculture. The technical framework helps us to make these processes environmentally friendly and sustainable.

Bio-based fertiliser shelf-life

Our liquid bacterial spore-based fertilisers have a shelf life of up to four years at room temperature. Our dry products usually have an even longer shelf life. This makes them quite competitive with conventional fertilisers. The fertilisers that are developed in the framework of the SUSFERT project are designed to have a long shelf-life.

ABiTEP wish for agricultural biologicals

Our goal for this project is to develop, together with our partners, a new innovative, sustainable fertiliser. This solution should use renewable sources and reuse waste so that in the end we can offer the end user an environmentally friendly alternative to conventional fertilisers.

Furthermore, we hope that this project will create curiosity and confidence in organic alternatives in agriculture. With public relations, we strive for a better understanding, from the stakeholders, that the use of micro-organisms is a valuable component of crop management, and that the product registration processes should be simplified.

This blog was co-authored by Philippa Webb-Muegge, SUSFERT Communications, Head of ABiTEP Regulatory Affairs, Dr. Kristin Dietel and Head of ABiTEP R&D, Elisa Schwarz.

This project has received funding from the Bio Based Industries Joint Undertaking (BBI-JU) under the European Union’s Horizon 2020 research and innovation program under grant agreement No. 792021.

ABiTEP Head of Regulatory Affairs,

Dr. Kristin Dietel

Dr. Kristin Dietel studied biology with focus on microbiology and bacterial genetics at the University of Berlin, obtaining her PhD in biology in 2010. During her studies she aquired experience in the field of microbiology, bacterial genetics and the genetic modification of plants.

In 2010, she started at ABiTEP GmbH as a post doc and worked within the framework of many different national and EU funded scientific projects to develop sustainable and environmentally-friendly solutions on the basis of micro-organisms.

The research interests of Dr. Dietel are in the field of plant-growth promoting bacteria, the mode of action regarding plant-microbe interactions, as well as studying the factors that influence the efficacy of microbial products. Her major passion is to translate scientific knowledge into sustainable, ecological and pragmatic solutions for agriculture and horticulture.

Coping with constantly increasing requirements for the approval of biological products, and the permanently increasing demand for ABiTEP products worldwide, lead to the decision to change the focus of her work from R&D to managing Regulatory Affairs for ABiTEP products. She is now Head of Regulatory affairs at ABiTEP. Dr. Dietel is an author and co-author of more than 30 peer reviewed publications and a co-inventor of a patent.


Head of ABiTEP R&D, Elisa Schwarz

Elisa is a 32-year-old country-born German from Brandenburg which is situated West of Berlin.

She studied biotechnology at the Technical University of Berlin with two main focus areas: Medical Biotechnology and Industrial Biotechnology. Her bachelor thesis was carried out at the Robert Koch-Institute on mumps-infected cells. She joined ABiTEP for her Masters thesis where she wrote about the development of a fermentation process of Bacillus subtilis for a biological cleaning agent.

After seven years of study she took a year off to work and travel in Australia. She worked on a cattle and sheep farm, as well as on a vineyard. She then backpacked her way through South East Asia.

She joined ABiTEP in the research and development department in 2016 and two years later she became Head of ABiTEP R&D.