Rainforest fungus generates biodiesel, may drive energy of the future
Jeremy Hance, mongabay.com
November 4, 2008
A fungus recently discovered in the Patagonian rainforest has shocked biologists and environmentalists: the fungus produces gas almost identical to diesel. In a paper announcing the discovery in Microbiology, scientists state that they believe the fungus, called Gliocladium roseum, could become an incredibly efficient green energy source.
“This is the only organism that has ever been shown to produce such an important combination of fuel substances,” said Professor Gary Strobel from Montana State University.
Gliocladium roseum makes a variety of molecules of hydrogen and carbon like those found in diesel. The scientists have named Gliocladium roseu’s fuel myco-diesel. The researchers found that when grown in a lab the fungus produced myco-diesel even closer to diesel used in cars.
The fungus proved to have another advantage, it grows on a tree’s cellulose. “When crops are used to make biofuel they have to be processed before they can be turned into useful compounds by microbes,” said Strobel. “G. roseum can make myco-diesel directly from cellulose, the main compound found in plants and paper. This means if the fungus was used to make fuel, a step in the production process could be skipped.”
Cellulose is an indigestible part of a plant that binds the plant and allows it to stand. When treated with specific enzymes the cellulose turns into sugar; microbes are then used to ferment this sugar creating an ethanol that can be used as fuel.
“We were very excited to discover that G. roseum can digest cellulose. Although the fungus makes less myco-diesel when it feeds on cellulose compared to sugars, new developments in fermentation technology and genetic manipulation could help improve the yield,” said Strobel. “In fact, the genes of the fungus are just as useful as the fungus itself in the development of new biofuels.”
“Gliocladium roseum lives inside the Ulmo tree in the Patagonian rainforest,” Strobel said, describing how his team stumbled on the fungus. “We were trying to discover totally novel fungi in this tree by exposing its tissues to the volatile antibiotics of the fungus Muscodor albus. Quite unexpectedly, G. roseum grew in the presence of these gases when almost all other fungi were killed. It was also making volatile antibiotics. Then when we examined the gas composition of G. roseum, we were totally surprised to learn that it was making a plethora of hydrocarbons and hydrocarbon derivatives. The results were totally unexpected and very exciting and almost every hair on my arms stood on end!”