Mascoma advances ethanol research

Scientists at the Mascoma Corporation — a Lebanon, N.H. company founded by two Dartmouth professors — have successfully demonstrated a new and more cost-effective way to produce biofuel from plant matter by reprogramming bacteria and yeast cells to digest the organic material, the company announced earlier this month.

“Mascoma was formed to develop this technology,” Jim Flatt, executive vice president of research, development and operations at the company, said in an interview with The Dartmouth.

The advances make biofuel production more commercially viable, he said.

Mascoma has developed the technique of consolidated bioprocessing, which integrates a multi-step process for producing ethanol into a single step. The company’s hallmark technology utilizes the metabolic capabilities of microorganisms to convert plant matter into renewable fuel.

A 2005 U.S. Department of Energy research agenda stated that “[Consolidated bioprocessing] is widely considered to be the ultimate low-cost configuration for cellulose hydrolysis and fermentation.”

The Mascoma research team’s next step is to scale up its technology for practical use, Flatt said. Engineers and operators at the company’s plant in Rome, N.Y., will adapt the methods developed in the Lebanon laboratory for use on larger equipment.

Mascoma plans to launch a commercial venture using its technology by the end of next year, Flatt said. Company officials are in the process of identifying a location for a commercial office and securing funding for the project, he said.

“Our principal goal, both technology- and business-wise, is to make renewable second-generation cellulosic feedstocks available for production of transportation fuels and eventually chemical fuels,” he said, referring to the use of non-food plants like switchgrass and wood products to produce alternatives to fossil fuels.

One of the announced advancements involves the bacterium Clostridium thermocellum, which is naturally found in compost, Flatt said. Unmodified, the bacterium efficiently degrades cellulose to produce a mixture of ethanol and other organic waste products. Scientists at Mascoma have genetically altered the bacteria to produce predominantly ethanol, significantly reducing unwanted waste products and increasing the amount of ethanol that can be produced, Flatt said. The genetically modified bacteria now produce almost 6-percent weight by volume ethanol from cellulose, an increase of 60 percent in what Mascoma scientists reported last year, according to a Mascoma press release.

Mascoma was also able to genetically alter brewing yeast, enabling it to convert cellulose into ethanol, according to the release. Mascoma scientists achieved this by introducing genes that code for cellulase — an enzyme that breaks down cellulose — into the yeast genome, Flatt said.

Previous methods for producing biofuels have relied on complex chemical processes that require expensive equipment and produce unusable by-products, Flatt said.

“By integrating those activities in one sort of microbial operating system, we’re able to, in principal, significantly reduce the complexity of the process and of operating and capital costs, which are the current barriers,” he said.

The technology reflects work conducted at Mascoma’s laboratory at the Dartmouth Regional Technology Center in Lebanon as well as at partner research facilities, including VTT Technical Research Centre in Finland and Stellenbosch University in South Africa.

Mascoma collaborates with Thayer School of Engineering professor Lee Lynd, whose research team contributed to the results announced earlier this month, Flatt said. Lynd, one of Mascoma’s co-founders, currently serves as chief scientific officer of the company.

Other biofuel companies use different techniques to produce ethanol that may currently be more commercially viable, Flatt said, though he added he believes Mascoma is still a leader in the field.

“There are only a handful of companies that both have the critical mass and are sufficiently advanced and that have built facilities to prove that,” he said. “Mascoma is in that group.”

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