SerAZel" university project seeks alternative to animal culture media in cell research

The importance of cell and tissue research has increased greatly in recent years. This has also increased the need for various nutrient fluids with which the cells can be cultivated. These are usually produced from animal products. In the "SerAZel" project at Bremerhaven University of Applied Sciences, doctoral students Hanna Eisenberg and Svenja Hütker are looking into the question of whether microalgae can be the basis for an alternative nutrient medium. The first trials will start soon. 
A nutrient fluid that is often used in cell research is fetal calf serum (FCS). This is considered to be particularly pure and free of defence substances that could harm the cell culture. However, its use is not only expensive, but also ethically controversial. Because many of the serum's ingredients are unknown, it has to be extracted from the animals themselves. In the process, millions of calves die every year before they are born. The project goal is therefore to replace this serum as completely as possible with a nutrient medium based on algae.

The preliminary work has already started. Hanna Eisenberg cultivates red algae in the laboratory for plant cells at Bremerhaven University of Applied Sciences, from which the plant nutrient medium is to be created. "We extract different classes of substances from the cells of the red algae, for example proteins or lipids. In this way, we can subsequently test the animal cells to see which substances in the algae are suitable as a nutrient medium and which are not," says Eisenberg. The red algae are cultivated in a special reactor in which optimal environmental conditions prevail. "Red algae like extreme locations. We experiment with different pH values and temperatures and investigate under which conditions they grow particularly well," adds the scientist.

When the algae extracts are ready, Svenja Hütker takes over. The doctoral student works in the animal cell laboratory and is currently preparing everything for the first experiments: "For our investigations, we want to cultivate animal cells in different culture media. Our goal for the next few weeks is first of all to ensure that there is enough protein in the extracts, i.e. that the algae serum has a similar protein concentration to the FCS. If the serum is not sufficient to maintain cell growth, we use calf and algae serum in different mixing ratios. To be able to interpret the results, we always run a control group with pure FCS. This allows us to investigate how the different serums affect cell growth and whether some compositions are possibly even toxic for the cells," says Hütker. 

The right timing is also important in the experiments. "Animal cells are little divas. If you don't take them out of the culture flasks at the right moment and put them in a nutrient medium, they die. However, you must not transfer them too early either, because then there are too few in the nutrient fluid. An example: If my cells are theoretically ready for the experiment, but I don't have any samples yet, then I have to transfer cells. But if they are freshly transplanted, I can't start an experiment because I have too few cells and then everything is delayed," says Hütker. When Hanna Eisenberg brings samples over, there must always be enough cells to start the experiments immediately. The two doctoral students therefore work closely together and exchange information about the current status of their work. 

If it turns out in the project that red algae are suitable as a nutrient medium for animal cells, this would have another advantage: since their ingredients are already used in medical and cosmetic products, the algae could be almost completely utilised. In the future, it will also be investigated whether cell research can be made even more sustainable. "The special thing about red algae is that they grow on sugar sources. For example, one could use leftovers from food production to cultivate the algae. That would be an additional sustainability aspect," says Prof. Dr. Imke Lang, who heads the project together with Prof. Dr. Felicitas Berger. To ensure that aspects of economic efficiency are also taken into account, SUPREN GmbH is supporting the project as a project partner.

The project is funded by the Federal Ministry of Education and Research (BMBF) and the Project Management Organisation Jülich (PTJ).