Mould makes corny fuel

(ISU) researchers have used mould to convert corn fibre into ethanol, a discovery which could turn by-products of corn milling into another source of fuel.

Tony Pometto, ISU professor of food science and human nutrition, has isolated a particular fungus that he and other researchers have used to successfully convert corn fibre that’s typically used for animal feed into ethanol.

The discovery could boost US ethanol production by about 4 per cent, or 606 million litres a year, said Hans van Leeuwen, an Iowa State professor of civil, construction and environmental engineering.

“I believe this is a breakthrough,” said van Leeuwen, the leader of the research project. “But I also want to caution that we need to do a lot more research.”

So far, the researchers have demonstrated they have a process that can convert corn fibre, a by-product of the wet milling process that produces corn syrup, into fuel-grade ethanol on a very small scale. the next step is to try it on a larger, pilot scale and experiment using other by-products of corn processing.

Van Leeuwen wants to see how the process works on distillers’ dried grains, a by-product of the dry milling process that’s typically used to convert corn kernels into ethanol.

The mould produces enzymes that break down corn fibre into the simple sugars that are fermented into ethanol. Pometto said corn fibre, a form of lignocellulose which forms the structure of a plant’s cell walls, is particularly tough.

The researchers’ techniques for working with mould and corn fibre to produce ethanol are now being reviewed for a possible patent. Van Leeuwen thinks their discovery has potential for the ethanol industry.

After all, van Leeuwen said, “We’re not using harsh chemicals, high temperatures, high pressure or expensive enzymes to do this.”