Ephedra Temporal range: | |
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Ephedra viridis | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Gymnospermae |
Division: | Gnetophyta |
Class: | Gnetopsida |
Order: | Ephedrales |
Family: | Ephedraceae |
Genus: | Ephedra L. [1] |
Type species | |
Ephedra distachya | |
Global range of Ephedra | |
Synonyms [2] | |
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Ephedra is a genus of gymnosperm shrubs. The various species of Ephedra are widespread in many arid regions of the world, ranging across southwestern North America, southern Europe, northern Africa, southwest and central Asia, northern China and western South America. [2] It is the only extant genus in its family, Ephedraceae, and order, Ephedrales, and one of the three living members of the division Gnetophyta alongside Gnetum and Welwitschia.
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 is the origin of the name of the stimulant ephedrine, which the plants contain in significant concentration.
The family Ephedraceae, of which Ephedra is the only extant genus, are gymnosperms, and generally shrubs, sometimes clambering vines, and rarely, small trees. Members of the genus frequently spread by the use of rhizomes. [3]
The stems are green and photosynthetic. [4] 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. [3]
The plants are mostly dioecious, with the pollen strobili in whorls of 1–10, each consisting of a series of decussate [5] bracts. The pollen is furrowed. The female strobili also occur in whorls, with bracts which fuse around a single ovule. Fleshy bracts are white (such as in Ephedra frustillata ) or red. There are generally 1–2 yellow to dark brown seeds per strobilus. [3]
The genus Ephedra was first described in 1753 by Carl Linnaeus, [6] [7] [8] and the type species is Ephedra distachya . [7] The family, Ephedraceae, was first described in 1829 by Dumortier. [6] [9]
The oldest known members of the genus are from the Early Cretaceous around 125 million years ago, with records being known from the Aptian-Albian of Argentina, [10] China, [11] Portugal and the United States. [12] The fossil record of Ephedra outside of pollen disappears after the Early Cretaceous. [13] Molecular clock estimates have suggested that last common ancestor of living Ephedra species lived much more recently, during the Early Oligocene around 30 million years ago. [14] However, pollen modified from the ancestral condition of the genus with branched pseudosulci (grooves), which evolved in parallel in the living North American and Asian lineages is known from the Late Cretaceous, suggesting that the last common ancestor is at least this old. [13]
Phylogeny of Ephedra [15] [16] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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As of June 2021 [update] , Plants of the World Online accepted the following species: [17]
The genus is found worldwide, in desert regions, but not in Australia. [3]
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. [3] They make up a significant part of the North American Great Basin sage brush ecosystem.
Remains of a buried Neanderthal found at Shanidar cave in Iraqi Kurdistan, over 50,000 years old was found associated with Ephedra pollen among those of other plants. While some authors have suggested that these represent plant remains deliberately buried alongside the Neanderthal, other authors have suggested that natural agents like bees may have been responsible for the accumulation of pollen. [19]
In addition, archaeological remains of Ephedra dating back 15,000 years have been discovered at Taforalt Cave in Morocco. Fossil cones of Ephedra were found concentrated in the cemetery area, specifically within a human burial. This finding suggests that, in addition to their medicinal properties, the plant held significant cultural and possibly ritual importance during the funerary activities performed by the people inhabiting the cave. [20]
The Ephedra alkaloids, ephedrine and pseudoephedrine – constituents of E. sinica and other members of the genus – have sympathomimetic and decongestant qualities, [21] and have been used as dietary supplements, mainly for weight loss. [22] The drug ephedrine is used to prevent low blood pressure during spinal anesthesia. [21]
In the United States, ephedra supplements were banned from the market in the early 21st century due to serious safety risks. [22] Plants of the genus Ephedra, including E. sinica and others, were used in traditional medicine for treating headache and respiratory infections, but there is no scientific evidence they are effective or safe for these purposes. [22]
Ephedra has also had a role as a precursor in the clandestine manufacture of methamphetamine. [23]
Alkaloids obtained from the species of Ephedra used in herbal medicines, which are used to synthetically prepare pseudoephedrine and ephedrine, can cause cardiovascular events. [21] These events have been associated with arrhythmias, palpitations, tachycardia and myocardial infarction. [21] Caffeine consumption in combination with ephedrine has been reported to increase the risk of these cardiovascular events. [21] [22]
The earliest uses of Ephedra species (mahuang) for specific illnesses date back to 5000 BC. Ephedrine and its isomers were isolated in 1881 from Ephedra distachya and characterized by the Japanese organic chemist Nagai Nagayoshi. His work to access Ephedra's active ingredients to isolate a pure pharmaceutical substance led to the systematic production of semi-synthetic derivatives thereof and is still relevant today. 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 pharmaceuticals. E. sinica and E. distachya 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%. [24]
For a review of the alkaloid distribution in different species of the genus Ephedra see Jian-fang Cui (1991). [25] 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. [26]
Ephedra distachya is a shrub in the family Ephedraceae that stands about 25 cm to 50 cm high. The shrub grows in many parts of the world, including southern and central Europe and western and central Asia. Its local names include somlatha. Ephedra distachya lives on grey dunes which are fixed and stable sand dunes that are covered in continuous vegetation.
Gnetophyta is a division of plants, grouped within the gymnosperms, that consists of some 70 species across the three relict genera: Gnetum, Welwitschia, and Ephedra. The earliest unambiguous records of the group date to the Jurassic, and they achieved their highest diversity during the Early Cretaceous. The primary difference between gnetophytes and other gymnosperms is the presence of vessel elements, a system of small tubes (xylem) that transport water within the plant, similar to those found in flowering plants. Because of this, gnetophytes were once thought to be the closest gymnosperm relatives to flowering plants, but more recent molecular studies have brought this hypothesis into question, with many recent phylogenies finding them to be nested within the conifers.
Ephedra is a medicinal preparation from the plant Ephedra sinica. Several additional species belonging to the genus Ephedra have traditionally been used for a variety of medicinal purposes, and are a possible candidate for the soma plant of Indo-Iranian religion. It has been used in traditional Chinese medicine, in which it is referred to as Ma Huang, for more than 2,000 years. Native Americans and Mormon pioneers drank a tea brewed from other Ephedra species, called "Mormon tea" and "Indian tea".
There has been much speculation as to the botanical identity of soma or haoma. Soma is a plant described in Hindu sacred texts including the Rigveda, while haoma is a plant described in the Avesta, a collection of Zoroastrian writings. Both names are derived from the Proto-Indo-Iranian *Sauma. Proposed candidates include various species of plants and or fungi. Traditional etymology of Indian Soma is Somalata used traditionally by the Srauta Brahmins called Somayajis whereas the Avestan Haoma is an Ephedra, which are totally unconnected species sourced from different areas. European researchers suggest other plants, such as the perennial Peganum harmala, Nelumbo nucifera, Cannabis sativa, and the sugarcane species Tripidium bengalense ; while fungal candidates include the fly-agaric mushroom Amanita muscaria, the psilocybin-containing mushroom Psilocybe cubensis, and the ergot fungus Claviceps purpurea. Other scholarly proposals include mixtures of these candidates with each other and with other substances.
Ephedra sinica is a species of Ephedra native to Mongolia, Russia, and northeastern China.
Ephedra californica is a species of Ephedra, known by the common names California jointfir, California ephedra, desert tea, Mormon tea, and cañatillo.
Ephedra funerea is a species of Ephedra, known by the common name Death Valley jointfir, Death Valley ephedra, or Mormon Tea.
Ephedra trifurca is a species of Ephedra known by the common names longleaf jointfir and Mexican tea.
Ephedra viridis, known by the common names green Mormon tea, Brigham tea, green ephedra, and Indian tea, is a species of Ephedra. It is indigenous to the Western United States, where it is a member of varied scrub, woodland, desert, and open habitats. It grows at 900–2,300 metres (3,000–7,500 ft) elevations.
Ephedra fasciculata is a species of plant in the Ephedraceae family. Common names are Arizona ephedra, Arizona jointfir, and desert Mormon-tea.
Ephedra alata is a species of Ephedra. These plants are perennial and xerophytic gymnosperm shrubs.
Ephedra przewalskii is a species of Ephedra that is native to Central Asia, Mongolia, Pakistan, and parts of China.
Ephedra torreyana, with common names Torrey's jointfir or Torrey's Mormon tea, is a species of Ephedra that is native to the deserts and scrublands of the Southwestern United States and to the State of Chihuahua and northern Mexico.
Ephedra lomatolepis is a species of Ephedra that is native to Kazakhstan, Mongolia, Xinjiang in China, and Tuva in Siberia.
Ephedra cutleri, the Navajo ephedra or Cutler's jointfir, is a species of Ephedra that is native to the Southwestern United States.
Ephedra foliata is a species of gymnosperm in the Ephedraceae family. It is referred to by the common name shrubby horsetail. It is native to North Africa, and Southwest Asia, from Morocco and Mauritania east to Turkmenistan, Pakistan, and Punjab State in India.
Ephedra intermedia, with the Chinese common name of Zhong Ma Huang, is a species of Ephedra that is native to Siberia, Central Asia, Iran, Afghanistan, Pakistan, the western Himalayas, Tibet, Mongolia, and China.
Ephedra nevadensis, commonly known as Nevada ephedra, gray ephedra, Mormon tea and Nevada jointfir, is a species of gymnosperm native to dry areas of western North America.
Ephedra monosperma, also called Ephedra minima or dan zi ma huang, is small shrub in the family of Ephedraceae.
Leiospora is a genus of flowering plants in the family Brassicaceae. It includes eight species native to central Asia, ranging from Kazakhstan to Tajikistan, the Western Himalayas, Tibet, Xinjiang, Mongolia, and southern Siberia.