Microbe makes carbon-neutral ethanol from cellulose, other plant material

Venture-capital funds and other investors recently put millions of dollars into SunEthanol, a biofuels technology company in Amherst, Mass., that is working with a bacterium that converts all sorts of plant matter, including cellulose, into ethanol. The company is using research by University of Massachusetts Amherst microbiologist Susan Leschine, who has made it the focus of her work for the past decade and is the chief scientist at SunEthanol.

“The Q microbe . . . is highly efficient at converting biomass to ethanol. And it does so in a carbon-neutral process that doesn’t require the additional enzyme treatments usually accompanying bioethanol production," says Newswise, a research-reporting service. "The microbe’s enzymes are another property that makes it an ideal organism for use in large-scale production of ethanol from biomass. Usually, cellulosic ethanol production involves several steps: pre-treat the plant material mechanically or chemically to get rough biomass; treat rough biomass with enzymes that have been bought or made in a lab; add the fermenting organism; recover and purify the ethanol. But the Q microbe’s own enzymes are more than sufficient, eliminating a costly step and consolidating production into one tank. Low estimates are that this consolidated production reduces costs by 25 percent, says Leschine."

Newswise adds that the bacterium's ethanol-making process "is carbon neutral and can be carbon negative, depending on the biomass that’s being used, says Leschine. . . . While the fermentation process releases some carbon dioxide, that amount isn’t more than what the original plants took in and therefore isn’t adding carbon to the cycle the way petroleum products do. And if a plant such as switchgrass is used, which stores large amounts of carbon in its roots, the process is actually carbon negative, putting carbon that was in the atmosphere into the ground. Now that SunEthanol has secured its first round of funding, Leschine and her researchers are exploring the forms of biomass that microbe Q favors, optimizing pre-treatments and fermentation conditions." (Read more)