plane taking off

Jet fuel produced by common soil bacteria

Image credit: Dreamstime

Common bacteria typically found in soil can be used to generate alternative jet fuel through their production of an unusual carbon molecule, researchers have said.

“In chemistry, everything that requires energy to make will release energy when it’s broken,” said lead author Pablo Cruz-Morales from the Technical University of Denmark.

When petroleum jet fuel is ignited, it releases a tremendous amount of energy in order to give planes enough lift to escape gravity.

The researchers recreated a molecule called Jawsamycin - named after the movie Jaws because of its bite-like indentations - by using the common bacteria streptomyces.

“The recipe already exists in nature,” Cruz-Morales said. The jagged molecule is produced by native metabolism of the bacteria as they munch away on glucose.

Extract Containing Jawsamycin

Image credit: Pablo Morales Cruz

“As they eat sugar or amino acids, they break them down and convert them into building blocks for carbon-to-carbon bonds,” he said. “You make fat in your body in the same way, with the same chemistry, but this bacterial process has some very interesting twists.”

These twists, which give the molecules their explosive properties, are the incorporation of cyclopropane rings: rings of three carbon atoms arranged in a triangular shape.

“If you have bonds that are at a normal angle, an open chain of carbons, the carbons can be flexible and they get comfortable,” Cruz-Morales added. “Let’s say you make them into a ring of six carbons; they can still move and dance a little bit. But the triangle shape makes the bonds bend and that tension requires energy to make.”

After careful analysis, the team determined that the enzymes that were responsible for the construction of these high-energy cyclopropane molecules were polyketide synthases.

The fuel produced by the bacteria would work a lot like biodiesel. It would need to be treated so that it could ignite at a lower temperature than the temperature needed to burn a fatty acid, but when ignited it would be powerful enough to send a rocket into space.

“If we can make this fuel with biology there’s no excuses to make it with oil,” Cruz-Morales said. “It opens the possibility of making it sustainable.”

The researchers hope they can scale up the process so that the fuel produced could actually be used in aircrafts.

“The problem right now is that fossil fuels are subsidised,” said Cruz-Morales. “This is something that is not only related to the technology, but the geopolitical and socio-political constitution of the planet right now. You can see this as a preparation for the moment because we are going to run out of fossil fuels and there’s going to be a point, not far from now, when we will need alternative solutions.”

Another team of researchers previously developed a process to transform plastic waste into jet fuel.

Sign up to the E&T News e-mail to get great stories like this delivered to your inbox every day.

Recent articles