But as civilization learned more about the properties of this fungus, people were able not only to prevent the disease, but to harness some benefits from the fungus.
Dr. Scott Chilton, professor in the Botany Department of the College of Agriculture and Life Sciences, tells this story to students in his medicinal plants class as an example of how civilizations have adapted plants for medical purposes.
It’s a story with an intriguing outcome: When people learned that sclerotia, which produced large purple fruiting bodies on rye, were the cause of ergotism, they avoided using flour tainted with the fungus. Later, midwives used sclerotia powder to reduce bleeding during childbirth, but the procedure was hazardous. When researchers learned to separate alkaloids, a class of chemicals in plant-based medicines, they discovered a range of substances to control post-partum bleeding, smooth muscle contractions and migraines, and to increase blood flow. Chemical modification of these alkaloids also led to the discovery of LSD, a powerful hallucinogen.
Like other universities, N.C. State has responded to renewed public interest in plant medicine. Chilton’s class is just one of the College’s endeavors in the field. Two years ago, the Botany Department hosted a two-day public seminar on “Explorations in Plant Medicine,” bringing together experts in ethnobotany and herbal medicines.
Dr. Jeanine Davis, head of the College’s Specialty Crops Program, also heads research on cultivating many herbs that have become popular supplements in recent years. N.C. State, though not alone in this work, is becoming recognized as a leader in the cultivation of woodland herbs. And graduate student Kathy McKeown has developed the world’s largest collection of echinacea germplasm, an herb popularly used to boost the immune system.
Since Chilton, a natural products chemist, began teaching the plant medicine class four years ago, it has become a favorite among undergraduates. Although the class does not deal with chemical structures, Chilton requires his students to have a year of freshman biology and chemistry in order to better understand the material.
The popularity of the class coincides with the rising use of herbal supplements, a trend that Davis attributes in part to aging baby boomers searching for a cure. “People of our generation don’t like the idea that we’re aging,” she says.
In addition, there is some public mistrust of the pharmaceutical industry and belief that plants are safer, she says. And elderly patients may turn to over-the-counter herbal treatments if they can’t afford their prescription medicines.
Chilton’s graduate student, Isaac Bruck, who lectures in the class, attributes the interest in plant medicine to increased media attention and renewed interest by the public and the pharmaceutical industry in natural remedies. But he points out that the reluctance of federal regulators to enter the herbal supplements arena leaves much responsibility for safe use of these products to the consumer.
“Consumers have to educate themselves more because there is so much on the market,” he says. “We are educating a new group of students who are interested in this type of medicine.”
The medicinal plants class deals with the history of medicine in many different cultures — Greek, Roman, Chinese and Asian-Indian. Early civilizations utilized plants for their medicinal value. Later, 19th century medicine began to sort out the alkaloids within the plants that produced the desired results, and 20th century chemists and pharmacologists began to synthesize and test analogs of alkaloids originally identified from plants. In recent years, people have returned to the plant-based remedies used by their grandparents.
Chilton also describes to the class the “doctrine of signatures,” a belief from the Middle Ages that God would provide a sign to show what ailment each plant was for. So the catalpa, with heart-shaped leaves, was used as a heart medicine. Students in the class must also learn to identify a dozen medicinal plants found in North Carolina. Among those are Jimson weed or Jamestown weed, pokeberry, poison hemlock and bitter sneezeweed.
Chilton brings in speakers, like Davis, from many different disciplines who add to the class content. Dr. John Riddle, N.C. State Alumni Distinguished Professor of History and an expert in the history of medicine, discusses the history of contraceptive use in Europe. McKeown discusses conservation of native medicinal plants in the United States.
Bruck, who studies ethnobotany, has brought together the disciplines of botany, chemistry and anthropology in his own research. He describes living and working with Kekchi Mayan Indians in a small village in Central America, where he learned how the culture uses plants as medicine. Dr. Cecil Brownie, toxicologist with N.C. State’s College of Veterinary Medicine, describes how veterinarians treat animals poisoned by plants.
Other speakers discuss traditional Chinese medicine, homeopathy and alternative medicine and Ayuorvedic, traditional medicine of India. The class learns about “wild crafting,” a traditional practice of harvesting herbs like ginseng in the wild and how this practice may lead to the extinction of some wild species.
Dr. Jeanine Davis has worked for years on developing cultivation practices for woodland herbs like ginseng, goldenseal and black cohosh. She tells Chilton’s class how manipulating the nutrients applied to these cultivated crops can alter the alkaloids that give a plant its medicinal value.
As director of the Specialty Crops Center, which seeks to identify and market high-value, niche-market crops, Davis is well aware of the effect that supply and demand can have on a crop’s viability. And while medicinal herbs show promise as a specialty crop, the market has been soft lately because supplies have outstripped demand, she says. These crops can be grown profitably, as long as the number of growers remains modest.
Though cultivation of these herbs seems quite possible, wild crafting has been a tradition in the state for many years. And commercial demand for these products has greatly increased the practice to the point that some species of wild herbs may become endangered, Davis says. Protecting the plants could mean prohibiting the practice of wild crafting and ending access to plants that some believe they have a right to harvest, she says.
Kathy McKeown, a doctoral student in botany and genetics, is concerned that the practice of wild crafting could impact the agricultural future for some native medicinal herbs. If wild species disappear, the opportunity to breed the best plants for cultivation will be lost. That’s why McKeown developed a germplasm collection for the medicinal plant echinacea.
“Wild plant populations are the reserves of genetic diversity,” McKeown says. “They are the foundation of modern agriculture.”
Echinacea, commonly known as cone flower, is native to the United States Southeast and Midwest. Because North America is the only place were echinacea grows wild, this germplasm is very highly desired around the world. Through a grant from the U.S. Department of Agriculture, McKeown collected seed from all known species of echinacea. The species she identified are being grown in Iowa by the USDA’s National Plant Germplasm System to maintain their genetic purity, and their seed will be distributed to those interested in breeding echinacea.
McKeown also maintains an echinacea germplasm collection at N.C. State. And the university’s JC Raulston Arboretum will soon become the first public garden with a collection of all known echinacea species, thanks to plants donated by McKeown.
Isaac Bruck’s interest in plants goes beyond their medicinal value. Bruck has studied indigenous cultures in the neotropics of Central and South America to learn how they use plants. For many of these cultures, plants are a primary source of materials for building the things they need to live, from houses to blow guns. And he is particularly interested in plants these cultures utilize for medicine and poison.
Each spring, Bruck leads groups of N.C. State students on trips to the places he has visited. This spring, students can spend their spring break in Costa Rica, studying the country’s different environments — rain forests, cloud forests and coast.
Though the university has no formal program in ethnobotany, Bruck says this is an excellent place to put together an interdisciplinary program of study in ethnobotany. His graduate committee includes a chemist, botanist and anthropologist.
With continued public interest
in medicinal plants, the College of Agriculture and Life Sciences stands
ready to provide information to the public, its students and those interested
in cultivating such plants for market. It is one example of how the
College utilizes its resources to respond when a trend presents an opportunity