Researchers working on biofuels have created a new class of sustainable biofuels that are strong enough to launch rockets using an unusual chemical produced by bacteria.
The candidate compounds outperformed the leading rocket and aviation fuels, JetA, and RP-1 in terms of expected energy density.
Using microbes as a biofuel for rockets
JOHN MACDOUGALL/AFP via Getty Images
Crude chemistry, which was originally developed by humans in the 1800s, is required to transform petroleum into fuels.
Meanwhile, for billions of years, microbes have been creating energy molecules made of carbon.
Knowing the benefits that biology can provide, a team of biofuel experts under the direction of Berkeley Lab drew inspiration from a remarkable antifungal molecule produced by Streptomyces bacteria to create a brand-new type of fuel with a projected energy density higher than even the most cutting-edge heavy-duty fuels currently in use, including the rocket fuels used by NASA.
These fuel candidate molecules, also known as POP-FAMEs (for polycylcopropanated fatty acid methyl esters), have extraordinary energy potential that stems from the structural chemistry of these compounds, as per ScienceDaily.
Each carbon-carbon bond in polycylcopropanated molecules is forced into a severe 60-degree angle by the presence of several triangle-shaped three-carbon rings.
More energy for burning can be produced by this strained bond's potential energy than by the bigger ring structures or carbon-carbon chains generally present in fuels.
These structures also make it possible for fuel molecules to condense firmly into a compact space, increasing the mass and hence the overall energy of fuel that can fit in any given tank.
Cyclopropane molecules caught the attention of Keasling, who is also a professor at UC Berkeley, for a very long period.
There are only two known instances of organic compounds with three carbon rings, both produced by Streptomyces bacteria that are nearly hard to culture in a lab setting, that he had searched the scientific literature for.
Fortunately, one of the compounds had been investigated and genetically examined since its antifungal characteristics were of interest.
The natural substance, jawsamycin, was found in 1990. Its unusual five cyclopropane rings give it the appearance of a jaw with sharp teeth.
Keasling's team, which included researchers from the JBEI and ABPDU, examined the genes from the original strain (S. roseoverticillatus) that encode the jawsamycin-building enzymes, and dug extensively through the genomes of related Streptomyces in search of a combination of enzymes that could produce a molecule with jawsamycin's toothy rings while skipping the other components of the structure.
The scientists aimed to mix up existing bacterial machinery to generate a new molecule with ready-to-burn fuel qualities, much like a baker rewriting recipes to create the ideal dessert.
The waste products of living things are used to make biofuel. Similar to how ethanol is manufactured for alcohol, plants are used to make ethanol, a common biofuel, as per News Medical.
Sugar beet, corn, and sugar cane are some of the primary plants used in the manufacturing of ethanol because they contain a lot of sugar, which yeast like Saccharomyces cerevisiae can readily ferment.
When compared to fossil fuels, the impact of biofuels on climate change is far lower.
According to studies, using biodiesel instead of diesel decreases emissions of carbon monoxide and smog-causing particulates by around 50%. It also reduces hydrocarbon emissions by 75% to 90%.
Additionally, it stops all sulfur emissions.
However, biofuels are not perfect. It is expensive to convert plant material into useable ethanol.
Also, there are ethical considerations.
Large amounts of land must be used to produce fuel, which reduces the land available for food production, which is a problem in developing countries with large populations to feed.
The amount of land needed also threatens vital ecosystems: In Brazil, there is a very real concern that rainforests will be cleared to grow sugar cane for this growing demand.
It is therefore argued by many scientists that producing biofuel in this manner is not a viable long-term solution to replace fossil fuels.
Many different scientific domains have a specific interest in microorganisms.
They are plentiful in the majority of the planet's habitats, and their utilization is fueling a minor but important technological revolution.
The plant cell wall component lignocellulose, which is composed of cellulose, hemicellulose, and lignin, is utilized by microbes to create ethanol for biofuels.
Cellulase is the enzyme that decomposes cellulose.
Researchers have been looking at where this enzyme comes from in various microbial species and conditions.
The termite gut and volcanic soil are two examples of these peculiar ecosystems.
