Asian Scientist (Oct. 17, 2013) – A researcher at the University of Queensland hopes to use a chemical found in lemons and other citrus fruits to make clean, renewable jet fuel.
Dr Claudia Vickers is modifying baker’s yeast to produce a synthetic form of the natural chemical limonene.
“Limonene is a volatile chemical that is best known for contributing to the smell of citrus fruits,” Dr Vickers said.
Limonene was first identified in turpentine oil in the late 1800s and is now used as a flavor and fragrance in foods, household cleaning products, and perfumes. It also holds promise as an anti-cancer agent.
Dr Vickers’ research at the Australian Institute for Bioengineering and Nanotechnology (AIBN) builds on earlier research which demonstrated that sucrose from sugarcane is one of the best biofuel feedstocks available in the Australian state Queensland.
The feasibility research had the backing of industry partners including Boeing, Virgin Australia, Mackay Sugar, IOR Energy and US biotech company Amyris.
“It might sound unlikely, but limonene one day could be a renewable, clean source of aviation fuel,” she said. “50 percent of a 747’s weight on take-off is its fuel. If you consider all the planes flying around in the world, that’s a lot of fuel – and non-sustainable fossil resource carbon – being emitted in the atmosphere.”
Limonene extracted from citrus peel had been used successfully as a jet fuel component in demonstration flights in the past. However, large-scale limonene production from citrus peel is impractical, Dr Vickers said, and producing it in yeast would likely provide a route to much greater yields of limonene which are easier to extract.
But limonene yields from the modified yeast are not yet high enough to be commercially viable, says Dr Vickers, and the researchers plan to further modify the yeast for improved yields. Further, the same technology could be used to make a variety of other sustainable products from limonene, including rubbers, plastics, and paints.
“Currently 80 percent of Australian sugar is exported. Instead of exporting sugar, we could export value-added products worth much more – or use them to replace non-renewable products in our own domestic market,” said Dr Vickers. “As the amount of easily-extractible fossil fuels decreases and the demand for alternatives to petrochemicals increases, these markets will become more and more important.”
——
Source: University of Queensland; Photo: David Sproule/UQ.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.
