Oct. 9, 2013
Gemma Reguera is an associate professor in the Department of Microbiology and Molecular Genetics at MSU. The Reguera lab studies the adaptive responses of microbes to their natural environment and exploits this knowledge to find novel biotechnical applications for microbial processes.
“Best wishes and make discoveries.” This was the note left for me by my office predecessor, microbiology and molecular genetics professor emeritus John Breznak, when I arrived on campus in 2006. Thanks to synchronicity, an increased societal interest in renewable energy and some innovative science, my time at MSU has been full of discoveries.
In addition to sharing office space and research interests, I also shared the same alma mater (the University of Massachusetts) as Breznak and Ph.D. mentor, Ercole Canale-Parola, a research pioneer in plant biomass degradation and ethanol production using fermentation processes with microorganisms.
His work really fascinated me—the fact that you could actually take a natural process that was occurring in the environment, bring it into the lab to study and then find an application for biofuel production. At the time, we could barely get funding for this type of research, so it’s been very gratifying to come to MSU and have the resources and support that I need to continue this important work.
For the past seven years, I’ve been building on Canle-Parola and Brenak’s work, developing a process that uses microbes to produce clean, cheap fuel and electricity from plant biomass. Most recently, I and members of my lab created a new biofuel production process that produces 20 times more energy than existing methods.
We’ve developed bioelectrochemical systems known as microbial electrolysis cells (MEC) that use natural bacteria to break down and ferment agricultural residue into ethanol. This platform is unique, because it also employs a second bacterium—Geobacter sulfurreducens—which removes all of the waste fermentation byproducts while producing electricity. With a little energy input, this electricity is converted into hydrogen, which can also be used as fuel.
These electrochemical systems use corn stover treated by the ammonia fiber expansion process pioneered at MSU by Bruce Dale, professor of chemical engineering and materials science.
Similar electrochemical systems have been investigated before, but maximum energy recoveries as power from corn stover hover around 3.5 percent. Our platform averaged 35 to 40 percent energy recovery just from the production of ethanol in the fermentation process. When the MEC generated hydrogen, the energy recovery increased to 73 percent.
The potential is definitely there to make this platform attractive for processing agricultural wastes. I think that we can scale up with commercial bioreactors and standard fermenters and take it from there.