German Researchers explore safe method for producing protein from air and water
GERMANY – German researchers are advancing the development of their sustainable technology, which produces micronutrient-enriched protein alternatives and vitamin B9 from microbes using renewable energy.
They aim to explore food safety, conduct technical and economic assessments, and evaluate market interest in this innovative solution.
Published on 12 September in the Cell Press journal Trends in Biotechnology, the technology harnesses the potential of microbes by feeding them hydrogen, oxygen, and carbon dioxide – a method with the potential to reduce carbon emissions from food production and create a sustainable protein alternative.
“This is a fermentation process similar to brewing beer, but instead of giving the microbes sugar, we gave them gas and acetate,” says corresponding author Largus Angenent of the University of Tübingen, Germany.
“We knew that yeast could produce vitamin B9 on their own with sugar, but we didn’t know if they could do the same with acetate.”
According to Angenent, one alternative for addressing the strain on the food system as the world population approaches 10 billion is growing proteins in bioreactors through biotechnology, rather than relying on crops to feed animals.
The researchers emphasized that the technology will not compete with farmers; rather, it will allow them to focus on producing vegetables and crops sustainably.
The team designed a two-stage bioreactor system that produces yeast rich in protein and vitamin B9, also known as folate, which is essential for functions such as cell growth and metabolism.
In the first stage, the bacterium Thermoanaerobacter kivui converts hydrogen and CO2 into acetate, a substance found in vinegar.
In the second stage, Saccharomyces cerevisiae, commonly known as baker’s yeast, feeds on acetate and oxygen to produce protein and vitamin B9.
The hydrogen and oxygen can be produced by splitting water using electricity from clean energy sources like wind turbines.
The researchers found that acetate-fed yeast produces about the same amount of vitamin B9 as yeast that feeds on sugar. Just 6 grams of the harvested dried yeast meets the daily vitamin B9 requirement.
The vitamin levels were measured by a team led by co-author Michael Rychlik at the Technical University of Munich, Germany.
For protein, the researchers found that the levels in their yeast exceed those in beef, pork, fish, and lentils. Eighty-five grams, or 6 tablespoons, of yeast provides 61 per cent of daily protein needs, while beef, pork, fish, and lentils meet 34 per cent, 25 per cent, 38 per cent, and 38 per cent, respectively.
However, the yeast needs to be treated to remove compounds that can increase the risk of gout if consumed excessively. Even after treatment, the yeast still meets 41 per cent of the daily protein requirement, comparable to traditional protein sources.
This technology aims to address several global challenges, including environmental conservation, food security, and public health. Running on clean energy and CO2, the system reduces carbon emissions in food production and decouples land use from farming, freeing up space for conservation.
The team’s yeast may also help developing nations overcome food scarcity and nutritional deficiencies by providing protein and vitamin B9.