A popular herb
Basic knowledge about Echinacea purpurea (aerial parts)
Introduction: Echinacea purpurea (aerial parts)
The intention of this post is to give you an easily digested synopsis of my research into this useful herb. Besides a few books with minor details and my college’s monograph, most of the information presented in this post are sourced from the American Herbal Pharmacopoeia’s monograph, which is one of the most comprehensive compilations of information on this particular herb, and many others. If you are an herbalist, scientist, or interested in the details of the scientific studies which have been done on this herb in greater detail, I would recommend reading their monograph, which is linked at the bottom of the page.
Name & Parts Used
Name derivation: Echinus (Greek, meaning sea urchin/hedgehog for its prickly bract); purpurea (Latin, for the purple dye of a Mediterranean shellfish).
Parts used: All aerial parts and root. Aerial parts are collected when flower is in bloom. In cultivation the lower part of the stem is often discarded, as too much stem is undesirable and because the lower leaves are often senescent. Flowers in June-July, harvested in second year of growth, roots can be harvested later on in the fall of the same year (ideally third year). Echinacea purpurea can technically be distinguished from other varieties of Echinacea by its fibrous root, but differentiation is overall difficult.
Growing & Harvesting Conditions
This variety (purpurea) is the easiest to grow. Propagated usually by seed or by root division. Perennial. sun/partial shade, prefers fertile, well-drained, high-lime loam, pH 6-8. Studies show that the most beneficial spacing between transplants is 12″, with 24-30″ between rows. If planting by seed, plants will sprout in 10-20 days. Cold stratification (keeping seeds in temperature of 2-4C for 30 days before planting) increased germination rates by 12-15%. Seed genetics are very important, with some plants having 2x the phytochemicals of others. A fertilizer of nitrogen or potassium is beneficial, with potassium being most beneficial; but a fertilizer of both potassium and nitrogen has been shown to have a negative effect. Grows in most areas of mid-east America, but is rarely found in the wild, due partially to over-harvesting. Drying is best at a temperature of 40C. For storage: dried form should not be in a powder, as the alkamides are susceptible to oxidation; cicorich acid is highly vulnerable to moisture; alkamide levels will fall if stored in an area around 30C, and exposure to light will reduce levels dramatically. Adulteration is uncommon, as this is the least expensive variety, and because it’s mostly cultivated (rather than wild-crafted).
Phytochemistry
There are four primary categories of compounds of medicinal interest from Echinacea purpurea (aerial): alkamides, polysaccharides, caffeic acid derivatives, and polyacetylenes. Note that no single compound has been shown to be superior in effect in comparison to the use of the whole plant.
Alkamides: Immuno-stimulatory and Anti-inflammatory effects. These are the chemicals which cause a numbing sensation when tasted. Lipophilic, can be extracted from alcohol (best at 90% alcohol), but little is extracted from water (tea). Found in higher quantities in the root.
Polysaccharides & glycoproteins: Interestingly these compounds are highest in the stems and in second year senescent plants (typically stems are of less medicinal value, and senescent plants are thought to be low-value). Believed to have immuno-stimulant action, though the research is unclear. More easily extracted from water.
Caffeic acid derivatives (phenylpropanoids, phenolics): The principle caffeic acids in this plant are cicorich acid and caftaric acid. Echinacea purpurea has the highest amount of these acids, compared to other Echinacea varieties. Cicorich acid has been shown to have immuno-stimulant, anti-oxidant, HIV anti-viral, and anti-hyaluronidase (anti-inflammatory/lymphatic) effects. They are hydrophilic polar compounds which can be extracted in water or alcohol. Best at 60% alcohol 1:6 ratio.
Polyacetylenes: Pentayne-ene is the most abundant. Found mostly in roots, but also some in the buds. Studies have shown near UV-mediated inhibition of certain strains of Candida, suggesting an anti-fungal effect. Soluble in lipids (oils) or 40-60% alcohol menstruum.
There are also some non-toxic alkaloids, flavonoids with anti-oxidant effects, trace minerals, and vitamin C. Melanin is also present and acts an immuno-stimulant, but typical preparations of this herb would be unlikely to extract it.
Conclusion of Phytochemistry: For the best extraction of alkamides (immuno-stimulant/anti-inflammatory), caffeic acids (immuno-stimulant/anti-oxidant/HIV anti-viral/lymphatic/anti-inflammatory), and polyacetylenes (anti-fungal), make/use a 60% alcohol tincture at a ratio of 1:6 (the alkamides prefer 90%, but are still present at a significant amount at 60%).
If the polysaccharides are desired (immuno-stimulant), an infusion (tea) is preferred (you’ll still get caffeic acids, but will lose the polyacetylenes and alkamides).
Therapeutics
One of the most popular herbs in North America, accounting for around 10% of herbal sales. It was used by the aboriginal people of North America, particularly in the Midwest and Plains regions of America. The original uses for Echinacea included treating wounds, bug-bites, snake-bites, etc. In the 1900s it became well-known for its wound-healing, anti-inflammatory, and anti-septic actions. Since then it has been the subject of more than 800 scientific studies, and today is used to treat colds, minor infections of the respiratory system, and minor wounds. But its uses may be more than those.
We know that Echinacea purpurea affects the immune system, but what is the “immune system”? Can you think of a clear answer to that question? Most people can’t, and neither can most scientists, believe it or not. The mechanism of action of Echinacea purpurea is generally unknown in the literature. Empirical studies show the positive effects, but not the mechanism.
I believe its mechanism lies in its action upon the lymphatic system. In vitro studies have shown in multiple verifiable instances, that the application of Echinacea purpurea stimulates macrophages, other monocytes, and Natural Killer cells (NK cells). These cells are part of what is known as the “immune system”, but they are also present and active in the more tangible, lymphatic system. That’s just my speculation, but the subject of what an immune system is, and the mechanism of action of Echinacea purpurea, are moreover unknown.
Potential adverse reactions: Side-effects are rare and usually mild. Serious adverse events can result from an Asteraceae allergy, which are reversible, and the chances can be lessened by using the herb sparingly at first, or by using the tincture form (as the pollen is less soluble in a water-alcohol medium). Minor side-effects include rash, digestive upset, migraine, nausea. These side-effects could be expected from a lymphatic herb, for if the internal eliminative organs are stressed, and the lymphatic system is stimulated to eliminate, the skin and digestive system will attempt to compensate, or some sickness will result from an inability to eliminate properly. Data regarding pregnancy and lactation is insufficient to give a conclusive answer to its safety, but it is reportedly the most-used herb during pregnancy with little evidence to suggest a negative effect (personally I would not recommend a lymphatic herb during pregnancy, it essentially appears to have a detoxification action and I don’t think pregnancy is the time for that).
Overall the risk:reward ratio appears favorable, with good evidence of effectiveness on the immune system.
Conclusion
A safe and effective herb, which appears to work primarily upon the lymphatic system. If used in combination with kidney, digestive, liver, or skin herbs, side-effects would likely be lessened.
Up until doing the research for this post, I’ve always been hesitant of Echinacea. I thought it was used for the suppression of cold and flu-like symptoms, symptoms (e.g. mucous discharge, etc.) which I believe are part of the healthy and normal cleansing mechanisms of our bodies. However, no evidence seems to suggest a suppressive action, and looking into some of my mentors’ lymphatic herbal formulas more closely, I see that some of them use Echinacea varieties extensively, sometimes as their primary lymphatic-formula herb. I will definitely be getting some of this herb for my own practice, and why not consider trying it for yourself before using over-the-counter or prescribed medications in the event of an acute cold or flu-like symptom?
