Developing further Echinacea products promises to help grow this popular herbal remedy market which attracted an estimated consumer spend of $126m in 2007, according to Nutrition Business Journal.
Known for its potential to treat infections and inflammation, and its possible effects on the human immune system, only a few Echinacea or coneflower species are currently cultivated as botanical remedies. But a wide range of other types may possess useful medicinal traits, said Mark Widrlechner, horticulturist with the Agricultural Research Service, North Central Regional Plant Introduction Station (NCRPIS),Ames, Iowa.
Classification
While previous studies have estimated the number of species at between four and nine, depending on classification criteria, Widrlechner, and partners at Iowa State University, have selected 40 different Echinacea populations for DNA analysis from the many populations conserved at the NCRPIS.
“What we had was really, really hard to sort out,” Widrlechner told AR magazine.
Although DNA analysis provided inconclusive results, Lankun Wu from Iowa State University lab focused on analyzing the same populations for chemical differences in root metabolites.
These metabolites, which are essential for survival and propagation, can vary widely among species and are thought to play roles in human-health effects.
“Using this approach, researchers were able to identify clear distinctions among all 40 populations,” according to the AR article.” These distinctions were organized into three composite profiles that accounted for almost 95 percent of the metabolite variation among the populations.”
The analysis suggested that Echinacea populations grouped together in ways that aligned with earlier Echinacea species assignments, based on plant morphology, supporting nine rather than only four distinct species.
Commercial producers
But more research is needed before commercial producers can benefit from the study, said Widrlechner. “Even though the metabolite study has given us some good species definitions, we still need to follow up with more genetic studies. It’s important to find the traits that may be medicinally beneficial,” he said.
Three varieties are currently used in herbal medicines: Echinacea purpurea, Echinacea engustifolia, and Echinacea pallida.
The researchers believe that when much of North America was covered with glaciers, Echinacea found southern refuges on both sides of the Mississippi River. But when the glaciers receded after thousands of years, the groups came together and began to hybridize. This is thought to have blurred previous genetic distinctions.
The original article, entitled No Easy Answers to Echinacea’s Evolution, was published in the March 2010 issue of Agricultural Research magazine.