NP307

Significant Accomplishments for FY 2006

Our Nation's need for biofuels to help meet our growing demand for
domestically-sourced, renewable transportation fuels is the major driver
behind ARS' research in bioenergy. Consequently, supporting research
that enables the continued growth in the two commercial biofuels --
ethanol and biodiesel -- is a priority for the ARS National Program in
Bioenergy and Energy Alternative. In addition, special cellulosic energy
crops, such as switchgrass, that can be cultivated on lands unsuitable
for corn or soybeans could significantly increase the amount of ethanol
that could be domestically produced without disrupting traditional
markets for food or feed. Therefore, another major component of NP307
focuses on energy crops. Finally, in order to provide farmers and
ranchers with power that is affordable and has relatively fixed costs,
NP307 also funds research that brings alternative sources of energy,
such as wind and solar, to rural America.

Component I: **Ethanol**

[Enzyme process that enables the commercial production of ethanol from
barley]{.underline}. Barley could be converted into ethanol if problems
with its high viscosity and low ethanol yields were overcome.
Researchers at Wynmoor, Pennsylvania, found that adding beta-glucosidase
enzymes to the starch hydrolysis step solves both problems of viscosity
and yield. This discovery should enable the building of ethanol plants
outside the corn belt and in barley growing regions such as the East
Coast, Northwest, and Upper Midwest. Having barley as a viable feedstock
could provide an additional one to two billion gallons of fuel ethanol
in the United States. (NP 307, Performance Measure 2.1.1)

[Producing valuable co-products for corn-based ethanol]{.underline}.
Researchers at Wyndmoor, Pennsylvania, determined that treating corn
germ with certain protease enzymes such as thermolysin or flavourzyme
produces peptides that could act as physiological modulators in the
human body. One such effect might lower blood pressure since these
peptides inhibit Angiotensin I Converting Enzyme. The ability to produce
valuable nutraceuticals from the proteins in corn would improve the
long-term business stability of corn-ethanol producers. (NP 307,
Performance Measure 2.1.1)

[Complete saccharification and fermentation of wheat straw to fuel
ethanol]{.underline}. Wheat straw contains 70 percent complex
carbohydrate, which can serve as a low cost feedstock for production of
fuel ethanol. Batch alkaline peroxide pretreatment, separate enzymatic
hydrolysis and fermentation (SHF), and simultaneous enzymatic
saccharification and fermentation (SSF) systems have been developed for
production of ethanol from alkaline peroxide pretreated wheat straw.
Researchers at Peoria, Illinois, have demonstrated that wheat straw
pretreated with alkaline peroxide can be completely enzymatically
saccharified into fermentable sugars. No common fermentation inhibitors
were produced. Both SHF and SSF approaches worked equally well for
production of ethanol from the pretreated wheat straw, both systems
capitalizing on an ethanologenic recombinant bacterium capable of
utilizing multiple sugars (glucose, xylose, arabinose). The research
will greatly contribute to the development of an integrated bioprocess
technology for fuel ethanol production from lignocellulose.

(NP 307, Performance Measure 2.1.1)

[Construction of a proteomic workcell]{.underline}. An automated method
to screen large numbers of samples is needed to help identify new
microbial strains and enzymes that can be used for efficient production
of ethanol and other value-added products from agricultural feedstocks.
In cooperation with Hudson Control Group, Inc., Springfield, New Jersey,
scientists at Peoria, Illinois, have constructed a plasmid-based
functional proteomic workcell for high-throughput assembly,
optimization, and modification of gene libraries and microbial strains.
Mechanical hardware has been integrated and controlling software
developed to provide a robotic platform that picks colonies, cultures
bacteria, prepares plasmid DNA, performs in vitro
transcription/translation, and assays enzyme activity. This workcell and
high-throughput strategy will ultimately be used for identifying strains
of ethanologenic yeast capable of fermenting xylose. (NP 307,
Performance Measure 2.1.1)

[Evolutionary enzyme design for improved biorefining of crops and
residues]{.underline}. The current ethanol industry uses a process
requiring gelatinization of corn starch at high temperature before the
addition of amylases enzymes for starch hydrolysis. Researchers at
Albany, California, conducted research under a CRADA with a private
sector partner to increase the hydrolysis rate of amylase family
enzymes. The result will benefit American farmers, make the fuel ethanol
price more competitive, and ultimately alleviate the dependency on
imported petroleum. (NP 307, Performance Measure 2.1.1)

Component II: **Biodiesel**

[Predicting cold flow behavior for biodiesel]{.underline}. Poor cold
flow behavior relative to petroleum-derived diesel is a major quality
issue in biodiesel fuels. Researchers at Peoria, Illinois, developed a
thermodynamic model to predict the cold flow properties of biodiesel
fuels. Results show that the model will be useful for screening
additives and determining the effects of contaminants on cold flow
properties. (NP 307, Performance Measure 2.1.1)

[Polymers from glycerol co-product]{.underline}. Given the forecasted
increase in biodiesel volume, there will also be increasing quantities
of glycerol, the major co-product of biodiesel production. Therefore,
finding new, value-added uses for glycerol will help ensure favorable
production economics for biodiesel manufacturers. Scientists at
Wyndmoor, Pennsylvania, were able to synthesize linear and hyperbranched
polymers from glycerol. Glycerol-based hyperbranched polymers represent
a new class of water-soluble polymers that could open up new markets for
glycerol. (NP 307, Performance Measure 2.1.1)

Component III: **Energy Alternatives for Rural Practices**

[Pumping from deep wells using renewable energy]{.underline}. Using a
traditional centrifugal pump powered by photovoltaic or wind energy, the
maximum water well depth is limited to about 165 feet. This limitation
precludes the use of renewable energy in many rangelands. Researchers at
Bushland, Texas, found that use of helical pumps instead allowed wind
power based well systems to pump from depths as much as 490 feet. These
systems should provide a means for farmers and ranchers to obtain water
using renewable energy in areas where ground water is quite deep. (NP
307, Performance Measure 2.1.1)

Component IV: **Energy Crops**

[Large scale sequencing of switchgrass and brachypodium for molecular
breeding of energy crops]{.underline}. Scientists at Albany, California,
were the first to publish gene sequences for Brachypodium, a model grass
plant, and switchgrass. These same scientists are also leading national
efforts to sequence the entire genome for Brachypodium as well as most
of the genes in switchgrass. These latter efforts are funded by DOE's
community sequencing program at the Joint Genome Institute. The sequence
data generated will accelerate efforts to breed better varieties of
perennial, herbaceous energy crops such as switchgrass. (NP 307,
Performance Measure 2.1.1)

[Developing agromonic practices for switchgrass production in Northern
Plains]{.underline}. Researchers in Lincoln, NE, completed a five year
field study for switchgrass production at the farm scale. Results
indicated that switchgrass could be grown in the Northern Plains with an
average yield of 3-4 dry tons/acre and at an average cost of \$45/ton.
Practices for stand establishment and fertilization/harvesting
management significantly impacted costs. (NP 307, Performance Measure
2.1.1)