Specification & Spread
Horsetail ephedra shoots (herb) – cormi (herba) ephedrae equisetinae
Horsetail ephedra — ephedra equisetina bunge
Joint-fir family — ephedraceae
Other names: Mongolian ephedra, sea grape.
It is a dioecious densely branched shrub 1-1.5 (2.5) m tall. The stocks are up to 4 cm in diameter, covered with a grey cork.
The branches are ligneous, thick, directed upwards, with oppositely located non-lignified, articulate, thinly wrinkled green annual shoots 20-30 cm long. The reduced leaves are represented by membranous reddish-brown scales, fused at the base.
The microstrobes develop on males, consisting of 2-3 covering scales and microsporophylls carrying pollen sacks. Megastrobes are formed on the females, consisting of one ovule surrounded by covering scales. After fertilization, the covering scales grow, become succulent and more than half cover the seed from the ovule.
Mature «cones» are oblong, 6-7 mm long, red or orange, fleshy, single-seeded.
It is a wind-pollinated plant. It «blossoms» in May, «pine cones» ripen in July. It is propagated by root shoots, so it grows as flower beds of 10-50 stems.
Spreading. Horsetail ephedra has a fairly extensive range. It grows in the mountain systems of Central Asia (Kyrgyzstan, Turkmenistan, Uzbekistan), Kazakhstan (rarely found on the plains), South Altai, in Mongolia, China.
Habitat. It grows in open sunny places, gravelly scree and stony slopes at an altitude of 1000-1800 m above sea level, often in such adverse conditions where other plants can not exist. Drought resistant, sun-loving.
Horsetail ephedra forms almost clean thickets, being the dominant of some plant communities, often occupying tens and hundreds of hectares. Ephedra shoots are a multi-tonnage raw material.
The chemical composition of ephedra
All parts of the plant contain alkaloids -
pseudoephedrine, which is the dextrophoric isomer of ephedrine. The greatest number of alkaloids is in green shoots (up to 3.5%), the smallest - in seeds (0.6%),
lignified shoots (0.8%),
the fleshy part of the cones (0.12%).
In the amount of alkaloids, (L) -ephedrine (85-90%) prevails.
It also contains:
condensed tannins (up to 7-10%),
ascorbic acid. Underground parts contain alkaloids.
ephedradines are derivatives of polyamines and cinnamic acids with hypotensive action.
Harvesting and storage of raw materials
Harvesting. The harvesting of the raw materials is carried out in accordance with the instruction in two terms: in early spring, in April, before the start of regrowth, and in July - October, after the end of the growth of young twigs. The second term is more important. Cut only green twigs without woody parts.
Security measures. On the treated bushes leave about 15% of green mass. Harvesters must take into account the biology of the plant. Ephedra is very sensitive to the mode of the harvesting. The annual harvesting for years in a row cause irreparable damage to plants. After cutting off the green shoots of ephedra, new branches grow due to the awakened buds, and recovery occurs very slowly during spring harvesting. When harvesting it is necessary to alternate thickets for exploitation. The break between the harvesting should be at least 2 years, and on heavily depleted thickets - 4-5 years. In view of the depletion of horsetail ephedra thickets (harvesting on the same areas, fuel use), the possibility of using other species is being conducted: intermediate or desert ephedra (E. intermedia Schrenk) and high ephedra (E. procera Fisch. Et Mey.). The possibility of cultivating horsetail ephedra is currently being studied.
Drying. It is not allowed to dry in the sun, because the shoots lose their natural colour. It is dried in the wind under a canopy or in the shade of trees and shrubs. The cut mass is laid so that it is blown by the wind, on a dry stony scree with stacks 80–100 cm wide and 1–1.5 m high, length is arbitrary, placing a «foundation» of stones under it so that the raw material does not dampen. The shrinkage reaches 45-50%. The artificial drying is allowed at a temperature not higher than 45 ºС.
Storage. It is stored with precautions, separately from other medicinal raw materials, in a dry, well-ventilated area. With increased humidity in the raw material, pseudoephedrine is formed, and the release of ephedrine decreases.
In order to avoid poisoning and irritation of the mucous membranes when packing and loading raw ephedra, wear gauze bandages and goggles, wash hands thoroughly after work.
External signs of raw materials
The raw materials are solid or partially crushed non-lumbering apical leafless (leaves reduced) shoots up to 25 cm long, up to 3 mm thick, bearing articulate branches with interstices about 2 cm long, 1.2-2 mm in diameter.
The colour of the raw material is light green. The smell is absent. Taste is not determined - raw poisonous (!).
Properties and application
Ephedrine belongs to the group of indirect adrenergic agonists, it indirectly stimulates alpha and beta adrenoreceptors. The basis of the mechanism of action of ephedrine is the ability to cause the release of norepinephrine from reserves in adrenergic systems and inhibit the reuptake of norepinephrine, due to which the effects of stimulation of adrenergic nerves are enhanced, and the action of externally introduced catecholamines is potentiated.
In addition, ephedrine reduces the activity of the enzyme monoamine oxidase and thereby prevents norepinephrine and adrenaline from destruction, enhancing their action, resulting in the stimulation of the function of synaptic formations.
Ephedrine stimulates the cerebral cortex and subcortical formations, unlike epinephrine ephedrine penetrates the blood-brain barrier.
- stimulates the respiratory center, deepens breathing, has antihypnotic (awakening) properties,
- increases blood pressure
- has a positive inotropic effect on the heart, increases the stroke volume of the heart, creating hyperdynamic syndrome, and
- increases peripheral vascular tone;
- relaxes the smooth muscles of the bronchi.
It improves blood circulation in the liver, clearly stimulates the function of the transverse muscles.
It expands the pupil, and mydriasis is not accompanied by an increase in intraocular pressure.
Application of ephedra
The raw materials are used to obtain preparation
«Ephedrine hydrochloride» .
The stimulating effect of ephedrine, the increase in physical and mental activity under the influence of ephedrine are used in various diseases.
Ephedrine is widely used:
- in diseases involving spasm of smooth muscles of the bronchi (bronchial asthma, whooping cough, bronchitis with asthmatic attacks, cough),
- in allergic diseases (hay fever, urticaria, vasomotor rhinitis, serum sickness).
Also it used for diseases it is accompanied by a decrease in blood pressure:
- with shock states as a result of infections, intoxication, acute injuries;
- with complications during surgery;
- for the prevention of lowering blood pressure during spinal anesthesia.
As an antagonist of preparations, ephedrine has been used for poisoning with these substances.
In case of vasomotor rhinitis, ephedrine (1 and 2% solutions) is used in the form of nasal drops as a vasoconstrictor and anti-inflammatory agent.
- Hypertonic disease,
- convulsive states
- as well as severe organic lesions of the heart muscle.
In order to avoid sleep disorders, ephedrine, as a rule, is not prescribed for the night.