Energy futureInvention turns trash into ethanol

Published 12 March 2008

Two University of Maryland researchers develop a process which turns trash into ethanol; the researchers found that a Chesapeake Bay marsh grass bacterium has an enzyme that could quickly break down plant materials into sugar, which can then be converted to biofuel

University of Maryland research that started with bacteria from the Chesapeake Bay has led to a process which may be able to convert large volumes of all kinds of plant products, from leftover brewer’s mash to paper trash, into ethanol and other biofuel alternatives to gasoline. That process, developed by University of Maryland professors Steve Hutcheson and Ron Weiner, is the foundation of their incubator company Zymetis. The Zymetis process can make ethanol and other biofuels from many different types of plants and plant waste called cellulosic sources. Cellulosic biofuels can be made from non-grain plant sources such as waste paper, brewing byproducts, leftover agriculture products, including straw, corncobs and husks, and energy crops such as switchgrass. When fully operational, the Zymetis process could potentially lead to the production of 75 billion gallons a year of carbon-neutral ethanol.

The secret to the Zymetis process is a Chesapeake Bay marsh grass bacterium, S. degradans. Hutcheson found that the bacterium has an enzyme that could quickly break down plant materials into sugar, which can then be converted to biofuel. The Zymetis researchers were unable to isolate the Bay bacterium again in nature, but they discovered how to produce the enzyme in their own laboratories. The result was Ethazyme, which degrades the tough cell walls of cellulosic materials and breaks down the entire plant material into bio-fuel ready sugars in one step, at a significantly lower cost and with fewer caustic chemicals than current methods. Hutcheson projects a $5 billion enzyme market for biofuels. The energy bill passed by the U.S. Senate in December mandates oil companies to blend in 21 billion gallons of cellulosic ethanol with their gasoline by 2022.