Associated Press
07-21-07
Ames scientist breaks down biofuel research
By THE ASSOCIATED PRESS
AMES — A laser beam bounces off a series of mirrors before diving into Emily
Smith’s microscope, where it scatters as it hits the membrane walls of plant
cells, producing a unique array of lightwaves.
The waves appear as light and dark crescent patterns on a computer monitor
next to the microscope. From them Smith hopes to identify which species of
plants contain the optimum raw material for ethanol production.
Ethanol manufacturers use corn now, but most experts see it as a transitional
feed stock. They believe a plant with more fuel efficiency, possibly switchgrass or
wood chips, eventually will replace corn as the chief ingredient in ethanol.
For now, breaking down the sugars in such plants remains too expensive
compared with using grain. But refineries in Emmetsburg and elsewhere hope to
change that in the next few years.
Smith, 31, is a research chemist and assistant professor at Iowa State
University. She’s beginning a two-year study that could result in dramatic
changes in Iowa agriculture.
The plant material Smith will study will come from corn plants, as well as a
variety of grasses and trees.
The more sugar a plant has, the higher the energy potential, she explained. The
more lignin, or woody connective tissue, the less energy. The trick is to identify a
plant with the optimum combination of the ingredients needed for distilling
ethanol.
When Smith’s laser passes through sugary cellulose and hemicellulose tissues,
the light scatters into patterns that create a fingerprint of sorts for the material.
Higher concentrations of lignin result in a much different fingerprint.
Optimal ethanol stock ‘‘will have a lot of cellulose and fairly little lignin,’’ Smith
said.
Before coming to Ames last August, Smith did research at the University of
Arizona under a professor who studied how a particular protein interacts to
contribute to cancer metastasis.
Smith was recruited by ISU to do similar cellular research. She arrived in Ames
with the idea of continuing to work with animal cells.
‘‘But after coming here, I realized it was a very wide-open opportunity, and there
were so many people on campus with expertise in plants,’’ she said.
She talked with agronomy professor Kenneth Moore and experts at ISU’s Plant
Sciences Institute on how she might contribute and decided she could help
determine which plants or parts of plants are best suited for ethanol production.
With her chemistry background, Smith brings a fresh perspective to ethanol
research, Moore said.
‘‘It’s really important to have bright, creative people like Emily involved,’’ he said.
‘‘Her tool can help us sort out the structural tissues in plants as they relate to
recovering the sugars’’ needed to produce ethanol, Moore said. ‘‘She can
prototype the cell wall structure we are looking for, and then we can go out and
find that in a plant.’’
The research has the potential to dramatically change the ethanol industry.
If Smith’s findings show that a particular type of grass is the best raw material for
ethanol production, it could be the catalyst to spur the conversion of millions of
acres of farmland from corn to grass production.
That in turn would require the creation of new harvesting and handling
equipment, new fertilization and cultivating techniques, Moore said.
‘‘It’s going to transfer agriculture in ways we can’t even imagine,’’ he said.
But that’s getting a bit ahead of the game.
Smith is just beginning her research under a grant to the Ames Laboratory from
the U.S. Department of Energy.
The first step, she said, is to establish controls that will determine which light
patterns mean what in plant cell structures. The controls include translating wave
patterns into mathematical formulas, which a computer can use to quickly make
comparisons between different plants, or different parts of the same plant.
Once the controls are in place, scientists can begin experiments to determine
which species have the most potential as ethanol stock.
They initially will test a variety of grasses and woods, including poplar and willow,
two fast-growing trees.
Another set of tests will determine ‘‘which tissues are more optimal for ethanol
production, stems or leaves or roots,’’ Smith said.
Eventually, the testing will include different growing conditions, including more or
less sunlight and water availability, and they will determine the best time for
harvest.
If Smith’s laser-beam fingerprinting works for biofuel crops, it can be used to
identify other plant materials that could be used to produce pharmaceuticals,
plastics and just about anything else.