Bug boosts biomass

Half the automotive fuel in the United States could be replaced with ethanol from renewable agricultural crops and forest wastes, says a

researcher who has developed a biotechnology “bug” that converts biomass and other farm wastes into fuel.

“We can reduce our dependence on imported oil and lower the price of automotive fuel by reformulating our gasoline with ethanol derived from inexpensive farm wastes,” said Lonnie Ingram, a professor of microbiology with UF’s Institute of Food and Agricultural Sciences.

His breakthrough technology – a genetically engineered E. coli bacteria – produces fuel ethanol from farm wastes such as corn stems, cobs and leaves. A related technology can be used to produce biodegradable plastics from biomass.

“With the cost of imported oil reaching record highs, we can use this new technology to produce ethanol for about $1.30 a gallon,” he said. “Ethanol will stretch the nation’s fuel supply and make gasoline burn more cleanly. Gasoline-ethanol blends also boost the octane rating of automotive fuel.”

Ingram says his genetically engineered E. coli bacteria is capable of converting all sugar types found in plant cell walls into fuel ethanol. Ingram’s organism produces a high yield of ethanol from biomass such as sugarcane residues, rice hulls, forestry and wood wastes and other organic materials.

The bioconversion technology is being commercialised with assistance from the US Department of Energy (DOE). BC International Corporation, based in Dedham, Massachusetts., holds exclusive rights to use and license the UF-engineered bacteria.

Until now, all of the world’s fuel ethanol has been produced from high-value materials such as cornstarch and cane syrup using yeast fermentations. In 2005, more than 4.5 billion gallons of fuel ethanol will be manufactured from cornstarch and used as automotive fuel.

He said his technology will further expand ethanol production by converting celluloic waste into fuel ethanol, more than doubling current ethanol production.

Ingram, who is director of the Florida Center for Renewable Chemicals and Fuels at UF, cited a recent report from the US Department of Agriculture and DOE that indicates more than one billion tons of biomass can be produced on a sustainable basis each year. Converting this to fuel ethanol could replace half of all imported petroleum in the United States.

Ingram said he genetically engineered the E. coli organisms by cloning the unique genes needed to direct the digestion of sugars into ethanol, the same pathway found in yeast and higher plants. These genes were inserted into a variety of bacteria that have the ability to use all sugars found in plant material, but normally produce a worthless mixture of acetic and lactic acids as fermentation products. With the ethanol genes, the engineered bacteria produce ethanol from biomass sugars with 90 to 95 percent efficiency.

“Until we developed this new technology, the chemical makeup of biomass prevented it from being used to make ethanol economically,” Ingram said. “Biomass is a much cheaper source of ethanol than traditional feedstocks such as cornstarch and cane syrup, but the cost of processing is higher.”

Greg Luli, vice president of research for BC International’s laboratory at the Sid Martin Biotechnology Center in Alachua, Florida, said the firm plans to build a 30-million-gallon biomass-to-ethanol plant in Jennings, Louisiana. The plant’s technology and process will be based upon Ingram’s genetically engineered bacteria.

“The facility, expected to be operational by the end of 2006, will convert organic waste into ethanol, a form of alcohol that can be used as an industrial chemical and as a clean-burning fuel,” Luli said. “Waste from the sugarcane industry in Louisiana will serve as the plant’s main feedstock.”

Ingram said the Governors’ Ethanol Coalition, which includes governors from 33 states, wants to expand federal mandates on using ethanol as a motor-vehicle fuel additive. The coalition, which is facing opposition from oil industry, is seeking federal incentives to boost that production to at least eight billion gallons a year by 2012.

“Energy independence is important to Florida and the nation, and it should be a 10-year national goal,” Ingram said. “Energy independence should be the ‘moonshot’ of our generation.”