Trash Today, Ethanol Tomorrow

UMD invention may lead to a major advance in biofuel production.

University of Maryland research that started with bacteria from the Chesapeake Bay has led to a process that 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.

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 less steps, at a significantly lower cost and with fewer caustic chemicals than current methods.

The process, developed by University of Maryland professors Steve Hutcheson and Ron Weiner, is the foundation of their incubator company Zymetis, which was on display earlier this month in College Park for Maryland Governor Martin O'Malley and state and university officials.

"The new Zymetis technology is a win for the State of Maryland, for the University and for the environment," said University of Maryland President C.D. Mote, Jr. "It makes affordable ethanol production a reality and makes it from waste materials, which benefits everyone and supports the green-friendly goal of carbon-neutrality."

Governor Martin O'Malley praised the university for "leading the nation in scientific discovery and technology innovation." He said, "we must continue to invest in Marylanders like Steve Hutcheson and in their revolutionary ideas to protect our environment, create jobs, and improve lives."

The Zymetis process can make ethanol and other biofuels from many different types of cellulosic sources including plants and plant waste. 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 has the potential to 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. 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 less steps, at a significantly lower cost and with fewer caustic chemicals than current methods.

In an e-mail interview, Hutcheson explained the process:

"Ethazyme is a slurry of enzymes that are produced by a bacterium called Saccharophagus degradans at very low cost. This bacterium has the capability to express the largest known diversity of enzymes that degrade the polymers found in the higher plant cell wall to their constituent sugars. The enzyme slurry can be targeted to whole plant material, the hemicellulose, or the cellulose. Because this bacterium can breakdown lignin, depending on the plant material, a less severe pretreatment may be required.

"A pretreatment is still required to sterilize the material and to make the wall more permeable to enzymes. In some cases, where a value stream can be produced, the lignin can be extracted and sold. It makes sense to extract the pentose-rich hemicellulose to facilitate processing of those sugars independently of cellulose. Finally, the lower the crystallinity of cellulose, the easier it is to digest. Some pretreatments are better at this than others. The advantage of the Ethazyme process is that the pretreatments do not have to separate the material into high quality cellulose and hemicellulose fractions. The mixtures of enzymes produced by this bacterium can work with more heterogeneous materials."

To see a video of how Ethazyme can break down newspaper, click here.

Hutcheson projects a US $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.

Hutcheson and Weiner won the university's Office of Technology Commercialization Inventor of the Year Award in 2007 in the Life Science category for their enzyme system invention.

Founded in 2006, Zymetis entered the university's MTECH VentureAccelerator Program, which provides hands-on business assistance to faculty and students interested in forming companies around university-created technologies.

Zymetis also sought expertise from MTECH's Bioprocess Scale-Up Facility (BSF) staff to determine how to mass-produce S. degradans. The BSF is part of the MTECH Biotechnology Research and Education Program, an initiative dedicated to research, education and the development of biotechnology products and processes for Maryland companies.