Yeast research fueling new uses for crop residues
By Tony Ten Haagen
Photo provided by David Umberger, Purdue News Service
Nancy Ho, a senior research scientist and leader of the Purdue Laboratory of Renewable Resources Engineering molecular genetics group, holds cultures of the new years strain (in the Petri dish) and a sample of ethanol.
Imagine a discovery that could protect the environment, lessen America's dependency on imported fuel, and create jobs throughout Indiana.
That's just what Purdue University researcher Nancy Ho accomplished when she engineered a yeast strain that converts agricultural residue (like corn stalks and wood chips into ethanol. And it only took her 25 years to do it.
"I felt as though I had a plan, even though many said it was not possible," said Ho, a senior research scientist and leader of the moledcular genetics group in the Purdue Laboratory of Renewable Resources Engineering (LORRE).
The fruits of her labor were realized when Iogen, a Canadian biotechnology company, began using her yeast last April for industrial test-scale ethanol production. Ho's yeast allows the company to produce ethanol from agricultural residue at a far more efficient rate than ever before.
Ethanol generates up to 30% less carbon dioxide than an equivalent amount of gasoline, according to Michael Ladisch, head of LORRE. Ethanol can also be used with the automobile industry's current infrastructure according to Bernard Tao, a Purdue agriculture engineering professor.
Researchers have been able to create ethanol from agricultural residues for more than 50 years, but the old yeasts were inefficient; nearly 30% of their by-product was unfermented ethanol. "That's fine in a research environment, but for industry standards, it is unacceptable," Ho said. Despite a lack of funds, Ho set out to develop a more efficient yeast strain when she took the lead of a small Purdue research group around 1980.
Ladisch said the ultimate goal is to keep the technology as close to Indiana as possible. He said he hopes they will be able to create jobs by selling the yeast to manufacturing companies that would then create ethanol plants. "If oil prices stay at $40 a barrel, it could be a legitimate business," he said. "But if they drop down to $10, then we can forget about it."
Tao compared Ho's innovation to the changes undergone by computers in recent years. "Imagine using a computer exclusively for word processing and spreadsheets," he said. "And now, with a few modifications, its wireless and can play television and music too. It immediately becomes more useful."
Ho's yeast, he said, represents an similar jump in fuel technology.