Sun hats (Echinacea)

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Sun hats
Purple coneflower (Echinacea purpurea)

Purple coneflower ( Echinacea purpurea )

Systematics
Euasterids II
Order : Astern-like (Asterales)
Family : Daisy family (Asteraceae)
Subfamily : Asteroideae
Tribe : Heliantheae
Genre : Sun hats
Scientific name
Echinacea
Monk

The sun hats ( Echinacea , pronunciation [ eçinat͡seːa ], and [ eçinaːt͡sɛa ]), even false sun hats or hedgehog heads called, are a genus of plants from the family of the daisy family (Asteraceae). The botanical genus name Echinacea is derived from the ancient Greek word ἐχῖνος echínos [ eˈkʰiːnos ] for sea ​​urchins (Echinoidea) and refers to the conspicuous, spiky chaff leaves that are typical of the genus and tower above the tubular flowers. All species are only native to eastern and central North America .

description

Echinacea species grow as perennial herbaceous plants that, depending on the species, usually reach heights of up to 140 cm. Except for Echinacea purpurea , all species have taproots. The upright stems are unbranched to branched. The plants can be hairy in different ways. The alternate , basal and distributed leaves on the stems have more or less long stalks. The simple leaf blade has one, three or five leaf veins . The leaf margin is usually smooth, sometimes serrated or serrated. The leaf surfaces are sometimes smooth or mostly hairy.

The "prickly" section of an inflorescence of the purple coneflower ( Echinacea purpurea ) with a bumblebee
Purple sun hat
Achenes of the purple coneflower ( Echinacea purpurea )
Narrow-leaved coneflower ( Echinacea angustifolia )
Prairie hedgehog head ( Echinacea pallida )

The head-shaped inflorescences are individually terminal on relatively long stems. The circular flower heads are 1.2 to 4 centimeters in diameter. There are 15 to 50 bracts in two to four rows ; they are almost the same to very different in shape and size. The inflorescence bases are almost spherical or cylindrical. There are orange-colored to reddish purple-colored chaff leaves that tower over the tubular flowers, as a striking feature of the genus, like small hedgehog spines (botanical name!). The flower heads contain eight to 21 ray-flowers and 200 to over 300 tubular flowers. The ungeschlechtigen ray florets (= ray flowers) are yellow, white, dark purple pink to light. The hermaphroditic, fertile tubular flowers (= disc flowers) are pink to reddish purple, greenish or yellow with five corolla lobes. The pollen is usually yellow, in Echinacea pallida it is usually white.

The three to four-sided achenes are light brown or two-colored with a dark brown band. The pappus is more or less crown-shaped with or without up to four prominent teeth.

Systematics

The genus name Echinacea was first published in 1794 by Conrad Moench in Methodus plantas horti botanici et agri Marburgensis , 591.

A synonym for Echinacea Moench is Brauneria Neck. ex Porter & Britton .

The original plant classification by Arthur Cronquist covered four Echinacea TYPES with two varieties, Echinacea pallida (with the two varieties Echinacea pallida var. Angustifolia and Echinacea pallida var. Pallida ), Echinacea atrorubens (with the varieties of Echinacea atrorubens var. Atrorubens and Echinacea atrorubens var. paradoxa ), Echinacea laevigata and Echinacea purpurea .

The latest processing of the genus is likely to include SE Binns: A taxonomic revision of Echinacea (Asteraceae: Heliantheae). in syst. Bot. 27, 2002, pp. 610-632. The list presented here comes from Ronald McGregor, with nine Echinacea species, two with two varieties each.

  • Narrow-leaved coneflower ( Echinacea angustifolia DC. ): With two varieties:
    • Echinacea angustifolia var. Angustifolia : It is found in western Canada, the central, and the northwestern United States.
    • Echinacea angustifolia var. Strigosa McGregor : It occurs in south-central Kansas, central Oklahoma and Texas.
  • Echinacea atrorubens Nutt. : It occurs in the US states of Kansas, Oklahoma and Texas.
  • Echinacea laevigata (Boynton & Beadle) Blake
  • Prairie hedgehog head ( Echinacea pallida (Nutt.) Nutt. ): It is found in the US states of Georgia, North Carolina, South Carolina and Virginia.
  • Yellow coneflower ( Echinacea paradoxa (Norton) Britton ) (Syn .: Echinacea atrorubens var. Paradoxa (JBSNorton) Cronq. ): With two varieties:
    • Echinacea paradoxa var. Neglecta McGregor (Syn .: Echinacea atrorubens (Nutt.) Nutt. Var. Neglecta (McGregor) Binns et al. ): It occurs in the US states of Oklahoma and Texas.
    • Echinacea paradoxa var. Paradoxa : It occurs in the US states of Missouri and Arkansas.
  • Purple coneflower ( Echinacea purpurea (L.) Moench )
  • Echinacea sanguinea Nutt. : It occurs in the US states of Oklahoma, Arkansas, Louisiana and Texas.
  • Echinacea simulata McGregor : It occurs in the US states of Missouri, Arkansas, Georgia, Kentucky and Tennessee. In Illinois she is a neophyte.
  • Echinacea tennesseensis (Beadle) Small : It is only found in the US state of Tennessee.

Of these, the following three Echinacea species have achieved the greatest medical importance:

Echinacea cultivation on Mount Adams in Washington State

Medical application

The coneflower is known as an ancient medicinal plant . Even the North American Indians allegedly used the coneflower as a medicinal plant against coughs , sore throats and tonsillitis . Today it is used to support respiratory or urinary tract infections and externally for poorly healing wounds. The species Echinacea purpurea , pallida and angustifolia are mainly used. The medical effect is controversial in science; different studies and meta-studies come to different results.

With the purple coneflower, the squeezed juice of the above-ground parts of the plant ( Echinaceae purpureae herba ) or the preparation is used as tea.

Medicines derived from some species of coneflower may have a stimulating effect on the immune system . This is to be done by influencing the activity of the bacterial tissue hyaluronidase.

Numerous ready-to-use drugs are commercially available.

effectiveness

A 2014 systematic review by the Cochrane Collaboration examined 24 controlled studies on the effectiveness of echinacea preparations in the prevention and treatment of colds. None of the studies showed a preventive effect on their own. On the basis of a statistical summary ( meta-analysis ) of the individual study results, however, the authors do not rule out a minor preventive effect. However, since the studies differed greatly in terms of their implementation and the plant parts used, the informative value of such a meta-analysis is low, so a clear assessment of the effectiveness is not possible. For the treatment of colds that have already occurred, the study situation is contradictory. Another systematic review from 2018 summarized studies on children and confirms the unclear study situation.

Despite the unclear evidence, the European Medicines Agency came to the conclusion in an assessment of the effectiveness in 2014 that the available scientific studies would confirm a positive effect of Echinacea-based medical products on the course of the disease in colds. However, this only applies to adults. According to the authorities, there is insufficient evidence of effectiveness in children.

In investigations by Commission E of the German Federal Health Office , data on the effectiveness of medicinal plants were collected. Among other things, the use of pressed juices from the roots of Echinacea angustifolia and Echinacea pallidae herba (narrow-leaved coneflower herb and pale-colored cone flower herb) was advised against. The reason is the plant's own poisons, which can have toxic effects with unexplained risks for pregnant women and allergy sufferers.

Studies published in 2004 and 2005 show that Echinacea contains substances that act similarly to cannabinoids , but with no psychomimetic effects. This fraction is summarized as "alkylamides" and has an immediately obvious resemblance to the body's own anandamides . These anandamides are ligands of the endocannabinoid receptors and the alkylamide fraction from Echinaceae binds to CB receptors in vitro . In 2006, researchers at the Swiss Federal Institute of Technology in Zurich showed that N-isobutylamides represent a new class of cannabino-mimetics that bind to the peripheral CB2 cannabinoid receptors on immune cells (T lymphocytes), but not to the CB1 receptors in the central nervous system. The so often postulated “immunomodulatory” effect could possibly take place via such CB receptors.

See also

Web links

Commons : Sun Hats  - Collection of Images, Videos, and Audio Files

swell

  • Lowell E. Urbatsch, Kurt M. Neubig, Patricia B. Cox: Echinacea. In: Flora of North America. Vol. 21, p. 88. (online) (section description, occurrence and systematics)

Individual evidence

  1. ^ Duden online: Echinacea
  2. ^ Eckehart J. Jäger, Friedrich Ebel, Peter Hanelt, Gerd K. Müller (eds.): Rothmaler Exkursionsflora von Deutschland . Volume 5: Herbaceous ornamental and useful plants . Spectrum Academic Publishing House, Berlin / Heidelberg 2008, ISBN 978-3-8274-0918-8 .
  3. ^ BR Schubert, G. Wagner: Botanical dictionary. Plant names and botanical terms. Stuttgart 2000, p. 194.
  4. JM Stowasser, M. Petschenig, F. Skutsch: Stowasser. Latin-German school dictionary. Oldenbourg, Vienna / Munich 2006, p. 171.
  5. Kathleen A. McKeown: A review of the taxonomy of the genus Echinacea. In: J. Janick (Ed.): Perspectives on new crops and new uses. ASHS Press, Alexandria, VA., 1999, pp. 482-489 ( PDF file, 96 kB ).
  6. a b c d e f g h i j Echinacea in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved January 21, 2019.
  7. The Plant of the Month September 2005: The Coneflower. ( Memento from July 21, 2012 in the web archive archive.today ) at Blumenbörsen.ch .
  8. ^ Echinacea Treatment for the Common Cold. ( Memento from August 4, 2012 in the web archive archive.today ) In: Clinical Infectious Diseases. 2005 (PDF file, 64 kB); Microsoft Encarta 2005.
  9. Sachin A Shah, Stephen Sander, C Michael White, Mike Rinaldi, Craig I. Coleman: Evaluation of echinacea for the prevention and treatment of the common cold: a meta-analysis. In: The Lancet Infectious Diseases . 2007, No. 7, p. 473. PMID 17597571 .
  10. E. Mutschler: Mutschler drug effects. 8th edition. Scientific publishing company, Stuttgart 2001.
  11. M. Karsch-Völk, B. Barrett et al. a .: Echinacea for preventing and treating the common cold. In: The Cochrane database of systematic reviews. Number 2, February 2014, p. CD000530, doi : 10.1002 / 14651858.CD000530.pub3 , PMID 24554461 , PMC 4068831 (free full text) (review).
  12. D. Anheyer, H. Cramer et al. a .: Herbal Medicine in Children With Respiratory Tract Infection: Systematic Review and Meta-Analysis. In: Academic Pediatrics . Volume 18, number 1, 2018 Jan - Feb, pp. 8-19, doi : 10.1016 / j.acap.2017.06.006 , PMID 28610802 (review).
  13. European Medicines Agency November 24, 2014: Assessment report on Echinacea purpurea (L.) Moench., Herba recens, p. 71 , accessed on March 16, 2018.
  14. Juerg Gertsch, Roland Schoop, Urs Kuenzle, Andy Suter: Echinacea alkylamides modulate TNF-α gene expression via cannabinoid receptor CB2 and multiple signal transduction pathways In: FEBS Letters . 577, 3, 2004, pp. 563-569.
  15. Karin Woelkart, Wei Xu, Ying Pei, Alexandros Makriyannis, Robert P. Picone, Rudolf Bauer: The Endocannabinoid System as a Target for Alkamides from Echinacea angustifolia Roots. In: Planta Medica . 71, 8, 2005, p. 701.
  16. Stefan Raduner, Adriana Majewska, Jian-Zhong Chen, Xiang-Qun Xie, Jacques Hamon, Bernard Faller, Karl-Heinz Altmann, Jürg Gertsch: Alkylamides from Echinacea Are a New Class of Cannabinomimetics: CANNABINOID TYPE 2 RECEPTOR-DEPENDENT AND -INDEPENDENT IMMUNOMODULATORY EFFECTS. In: Journal of Biological Chemistry . 281 (20), 2006, pp. 14192-14206.