Plants supply the air we breathe, feed us and protect us. Plant derivatives can be found in everything from fuel to clothes. Plants are a fundamental part of nature and of life, and without them humans and animals wouldn’t exist.
Plants also hold answers to producing healthier food, creating cleaner, renewable fuel and fighting devastating diseases. By altering a plant’s genes to produce vital chemicals or enhance yield, plant science researchers are developing solutions to support a growing population in a world of shrinking resources.
My research involves finding ways to create better forage crops, produce more viable biofuels and other bio-based products, and harness nature’s repertoire of natural chemicals to provide novel therapeutic agents. It all starts with understanding how plants work and envisioning what else they can be engineered to do.
Developing better biofuels
Scientists have long focused on developing clean, renewable fuel sources. But increasing concerns over limited oil supplies, fluctuating prices and the impacts of carbon dioxide emissions have spurred research on biofuels, particularly fuels made from plants.
Much of the gasoline that powers our cars today is blended with corn-based ethanol to be more environmentally friendly. Corn is a major crop — the primary feed grain in the U.S. and an ingredient found in a wide range of human foods and beverages. Moving ethanol production away from a corn-based system is important to lessen the strain on the world's food resources. While corn is relatively cheap and ubiquitous, it also takes a lot of energy to grow and replenish.
The University of North Texas has become a partner in the U.S. Department of Energy’s BioEnergy Science Center, organized from the Oak Ridge National Laboratory, and I am working with the center on a research project investigating how to develop liquid biofuels from genetically engineered switchgrass. Switchgrass is an ideal plant for creating biofuel because of its high productivity and adaption for growth in a wide area of the Southeast and Great Plains.
We are engineering switchgrass to make its cell walls easier to break down for fermentation to become biofuel. The carbohydrates in the plant’s cell walls are released and converted into ethanol.
It’s a great partnership because UNT is a growing hub for groundbreaking plant science where plant biologists and biochemists like me, in collaboration with chemists and engineers, are developing high-quality, high-yield crops and plant-based, sustainable resources.
And the BioEnergy Science Center is one of three major centers in the U.S. focused on finding scientific breakthroughs to make production of cellulosic biofuels cost-effective on a national scale. Doing so could reduce our reliance on fossil fuels.
Supporting healthier livestock
My area of plant science research — metabolic engineering — involves altering a plant’s genes or pathways so that the plant becomes a more viable resource, as in the case of switchgrass for biofuel.
We are using similar technology to increase the digestibility of alfalfa, the world’s No. 1 forage legume, which has an annual value of more than $8 billion in the United States alone.
My research group developed low lignin alfalfa, which can be more easily digested, in collaboration with a corporate partner. It will soon be commercialized. While most research has real-world applications, it’s important to find ways to bring it to the marketplace so it can have a true impact.
Alfalfa also impacts protein digestion in the animal’s rumen, which is part of the stomach. Traditional alfalfa used as feed for dairy cows causes bloating that not only is potentially lethal to the animal, but also is associated with reduced nitrogen uptake from the rumen. To create more livestock-friendly alfalfa, we are working to genetically introduce compounds called condensed tannins into alfalfa foliage. These compounds slow the rate of protein digestion in the rumen, resulting in less danger of bloating and improved nitrogen nutrition, which equates to more milk or meat production.
New approaches to Alzheimer’s treatment
One of the higher-visibility aspects of plant science research involves finding treatments and cures for diseases.
I’m part of a research team including Mount Sinai’s Ichan School of Medicine in New York and Purdue University’s Department of Food Science that is investigating how grape seed compounds affect the development of Alzheimer’s disease.
Our research, funded by a National Institutes of Health grant, continues a first-of-its-kind study indicating that grape seed compounds, related to condensed tannins, could help to prevent the development or delay the progression of Alzheimer’s disease in mice.
The current research shows that these compounds do indeed slow the progression of the disease, and now we are working on an explanation and proof of exactly what activity is happening in the brain. Having that explanation will allow us to say, for the first time, exactly how plant-derived chemicals can slow the progression of a major neurodegenerative disease.
Versions of the compound are needed for testing, so my lab will develop synthesized versions of the grape seed-derived compounds that actually reach the brain. Researchers at Purdue University will then compare the synthesized and natural compounds to verify that they are exact matches.
My lab also will develop a standardized procedure that other researchers will rely on to develop and test these compounds in the future. We then hope to provide other researchers on the team with a range of radio-labeled or “tagged” versions of the active compounds for studies on their mechanism of action.
It’s a cause that is personal to me because my mother suffered from Alzheimer’s.It’s heartening to think that a simple grape seed extract could prevent the onset of this complex, devastating disease. This is ultimately why I love plant science; it’s about finding new and life-changing ways to use a natural resource.
RICHARD DIXON is a Distinguished Research Professor at the University of North Texas and a member of the U.S. National Academy of Sciences. The Institute for Scientific Information has named him as one of the 10 most cited authors in the plant and animal sciences.