Ephedra (plant)

From Wikipedia, the free encyclopedia
  (Redirected from Ephedra (genus))
Jump to navigation Jump to search

Ephedra
Temporal range: Aptian–Recent
Green ephedra Ephedra viridis close.jpg
Ephedra viridis
Scientific classification e
Kingdom: Plantae
Clade: Tracheophytes
Division: Gnetophyta
Class: Gnetopsida
Order: Ephedrales
Dumort.[2]
Family: Ephedraceae
Dumort.[1]
Genus: Ephedra
L.[1]
Map showing the range of Ephedra
Global range of Ephedra
Synonyms[3]

Alloephedra Tao JR et Yang Y., 2003. Chaetocladus Nelson 1866 nom. illeg. Liaoxia Cao et S.Q. Wu, 1996

Ephedra is a genus of gymnosperm shrubs, the only extant genus in its family, Ephedraceae, and order, Ephedrales. The various species of Ephedra are widespread in many lands, native to southwestern North America, southern Europe, northern Africa, southwest and central Asia, northern China and western South America.[3]

In temperate climates, most Ephedra species grow on shores or in sandy soils with direct sun exposure. Common names in English include joint-pine, jointfir, Mormon-tea or Brigham tea. The Chinese name for Ephedra species is mahuang (simplified Chinese: 麻黄; traditional Chinese: 麻黃; pinyin: máhuáng; Wade–Giles: ma-huang; lit. 'hemp yellow').

Ephedra fragilis pollen cones
Ephedra distachya: ripe female cones with seeds

Description[edit]

The family, Ephedraceae Dumort., of which Ephedra is the only genus, are gymnosperms, and generally shrubs, sometimes clambering vines, and rarely, small trees. Members of the genus frequently spread by the use of rhizomes.[4]

The stems are green and photosynthetic.[5] The leaves are opposite or whorled. The scalelike leaves fuse into a sheath at the base and this often sheds soon after development. There are no resin canals.[4]

The plants are mostly dioecious: with the pollen strobili in whorls of 1-10, each consisting of a series of decussate[6] bracts. The pollen is furrowed. The female strobili also occur in whorls, with bracts which fuse around a single ovule. There are generally 1-2 yellow to dark brown seeds per strobilus.[4]

Distribution[edit]

The genus is found worldwide, in desert regions, but not in Australia[4]

Ecology[edit]

Shrubs of Ephedra major in Karvachar

Ephedraceae are adapted to extremely arid regions, growing often in high sunny habitats, and occur as high as 4000 m above sea level in both the Andes and the Himalayas.[4]

Taxonomy[edit]

The genus, Ephedra was first described in 1753 by L.,[7][8][9] and the type species is Ephedra distachya.[8] The family, Ephedraceae, was first described in 1829 by Dumortier.[7][10]

Medical uses[edit]

Plant as used in Chinese herbology (crude medicine)

Plants of the genus Ephedra, including E. sinica and others, have traditionally been used by people for a variety of medicinal purposes, including treatment of asthma, hay fever and the common cold.[11] The alkaloids ephedrine and pseudoephedrine are active constituents of E. sinica and other members of the genus. These compounds are sympathomimetics with stimulant and decongestant qualities and are chemically substituted amphetamines.

Pollen of Ephedra spp. was found in the Shanidar IV burial site in Iraq, which led to the suggestion that its use as a medicinal plant dates to over 60,000 years ago.[12] Paul B. Pettitt has stated that "[a] recent examination of the microfauna from the strata into which the grave was cut suggests that the pollen was deposited by the burrowing rodent Meriones persicus, which is common in the Shanidar microfauna and whose burrowing activity can be observed today".[13] It has been suggested that Ephedra may be the soma plant of Indo-Iranian religion.[14]

Adverse effects[edit]

Alkaloids obtained from the species of Ephedra used in herbal medicines, which are used to synthetically prepare pseudoephedrine and ephedrine, can cause cardiovascular events. These events have been associated with arrhythmias, palpitations, tachycardia and myocardial infarction. Caffeine consumption in combination with ephedrine has been reported to increase the risk of these cardiovascular events.[15]

Evolutionary history[edit]

The oldest known members of the genus are from the Early Cretaceous, with records being known from the Aptian-Albian of Argentina,[16]China,[17] Portugal and the United States.[18]

Species[edit]

Accepted species:[3]

Economic botany and alkaloid content[edit]

Earliest uses of Ephedra spp. (mahuang) for specific illnesses date back to 5000 BC. Ephedrine and isomers were already isolated in 1881 from Ephedra dystachia and characterized by the Japanese organic chemist Nagai Nagayoshi of the 19th century. His work to access Ephedra drug materials to isolate a pure pharmaceutical substance, and the systematic production of semi-synthetic derivatives thereof is relevant still today as the three species Ephedra sinica, Ephedra vulgaris and to a lesser extent Ephedra equisetina are commercially grown in Mainland China as a source for natural ephedrines and isomers for use in pharmacy. E. sinica and E. vulgaris usually carry six optically active phenylethylamines, mostly ephedrine and pseudoephedrine with minor amounts of norephedrine, norpseudoephedrine as well as the three methylated analogs. Reliable information on the total alkaloid content of the crude drug is difficult to obtain. Based on HPLC analyses in industrial settings, the concentrations of total alkaloids in dried Herba Ephedra ranged between 1 and 4%, and in some cases up to 6%.[20]

For a review of the alkaloid distribution in different species of the genus Ephedra see Jian-fang Cui (1991).[21] Other American and European species of Ephedra, e.g. Ephedra nevadensis (Nevada Mormon tea) have not been systematically assayed; based on unpublished field investigations, they contain very low levels (less than 0.1%) or none at all.[22]

References[edit]

  1. ^ a b Kramer KU, Green PS, Götz E (1990). Kramer KU, Green PS (eds.). The Families and Genera of Vascular Plants, Vol. 1: Pteridophytes and Gymnosperms. Berlin: Springer-Verlag. pp. 379–381. ISBN 3540517944.
  2. ^ "Ephedrales Dumort". EU-NOMEN. Retrieved 20 January 2016.
  3. ^ a b c Kew World Checklist of Selected Plant Families
  4. ^ a b c d e Judd WS, Campbell CS, Kellog EA, Stevens PF, Donoghue MJ (2007). Plant Systematics, a phylogenetic approach (3rd. ed.). Sinauer associates, Inc.
  5. ^ "Family "Ephedraceae"". Angiosperm Phylogeny Website. Retrieved 5 July 2019.
  6. ^ Messina A (2014). "VicFlora: Ephedraceae". Victoria, Australia: Royal Botanic Gardens Foundation. Retrieved 5 July 2019.
  7. ^ a b The Gymnosperm database: Ephedra. Retrieved 5 July 2019.
  8. ^ a b Linnaeus C (1753). Species Plantarum. 2. p. 1040.
  9. ^ Linnaeus C (1754). "Genera plantarum". p. 462.
  10. ^ Dumortier BC (1829). Analyse des familles des plantes, avec l'indication des principaux genres qui s'y rattachent. Tournay: J. Casterman aîné. p. 11.
  11. ^ Abourashed EA, El-Alfy AT, Khan IA, Walker L (August 2003). "Ephedra in perspective--a current review". Phytotherapy Research. 17 (7): 703–12. doi:10.1002/ptr.1337. PMID 12916063. S2CID 41083359.
  12. ^ Solecki RS (1975). "Shanidar IV, a Neanderthal Flower Burial in Northern Iraq". Science. 190 (4217): 880–881. Bibcode:1975Sci...190..880S. doi:10.1126/science.190.4217.880. JSTOR 1741776. S2CID 71625677.
  13. ^ Pettitt PB (2002). "The Neanderthal dead: exploring mortuary variability in Middle Palaeolithic Eurasia" (PDF). Before Farming. 1 (4): 1–26. doi:10.3828/bfarm.2002.1.4.
  14. ^ Rudgley R (1993). The Alchemy of Culture. London: British Museum Press. pp. 44–45. ISBN 0-7141-2711-6.
  15. ^ Skalli S, Zaid A, Soulaymani R (December 2007). "Drug interactions with herbal medicines". Therapeutic Drug Monitoring. 29 (6): 679–86. doi:10.1097/FTD.0b013e31815c17f6. PMID 18043467. S2CID 17042490.
  16. ^ Puebla GG, Iglesias A, Gómez MA, Prámparo MB (November 2017). "Fossil record of Ephedra in the Lower Cretaceous (Aptian), Argentina". Journal of Plant Research. 130 (6): 975–988. doi:10.1007/s10265-017-0953-1. PMID 28528483. S2CID 23766815.
  17. ^ Yang Y, Wang Q (2013-01-14). "The earliest fleshy cone of Ephedra from the early cretaceous Yixian Formation of northeast China". PLOS ONE. 8 (1): e53652. Bibcode:2013PLoSO...853652Y. doi:10.1371/journal.pone.0053652. PMC 3544918. PMID 23341964.
  18. ^ Rydin C, Pedersen KR, Crane PR, Friis EM (July 2006). "Former diversity of Ephedra (Gnetales): evidence from Early Cretaceous seeds from Portugal and North America". Annals of Botany. 98 (1): 123–40. doi:10.1093/aob/mcl078. PMC 2803531. PMID 16675607.
  19. ^ Sharma P, Singh R (December 2016). "Ephedra yangthangensis (Ephedraceae), a new species from Himachal Pradesh, India. Bangladesh". Journal of Plant Taxonomy. 23 (2): 195–8. doi:10.3329/bjpt.v23i2.30850.
  20. ^ Brossi A, ed. (1989). The Alkaloids: Chemistry and Pharmacology. 35. ISBN 0-12-469535-3.
  21. ^ Kim HK, Choi YH, Erkelens C, Lefeber AW, Verpoorte R (January 2005). "Metabolic fingerprinting of Ephedra species using 1H-NMR spectroscopy and principal component analysis". Chemical & Pharmaceutical Bulletin. 53 (1): 105–9. doi:10.1002/pca.2800020305. PMID 15635242.
  22. ^ Hegnauer R. (1962) "Chemotaxonomie der Pflanzen. I". Birkhauser Verlag, Basel; Switzerland, pp. 460–462 as cited in Roman MC (2004). "Determination of ephedrine alkaloids in botanicals and dietary supplements by HPLC-UV: collaborative study". Journal of AOAC International. 87 (1): 1–14. doi:10.1093/jaoac/87.1.1. PMC 2584348. PMID 15084081.

External links[edit]