Synonym
Ma-Huang (Ma-Astringent
taste, Huang -Yellow)
Biological
source
It
consists of dried young stems of Ephedra gerardiana, E. nebrodensis (India),
Ephedra sinica, Ephedra equisetina (China) Family: Gnetaceae
/ Ephedraceae.
Geographical
source
China, Pakistan, North
India, Australia, Kenya, Spain etc.
Morphological
features
•
This is an evergreen shrub which can grow up to 60 cm high.
• Ephedra has many different species.
• This plant is differentiated into 3 parts: root, stem and leaves.
• The plant is spread by the use of rhizomes.
• Stems are green, leaves are opposite in arrangement and whorled.
• The shape of leaves are scale like and have no resin canals.
• Seeds are yellow to dark brown in colour.
• The branches of this plant are slender, more or less broken aerial stems
which are woody in nature and branched only at the base.
Macroscopic Characters of Ephedra gerardiana
·
Woody, cylindrical.
·
Colour: Grey to greenish
·
Taste: Bitter
·
Stems contain numerous, fine and
longitudinal ridges.
— It
has Nodes, internodes, scaly leaves and terminal buds.
·
Shows internodes at 3-4 cm distance.
·
The diameter of node is about 1-2 mm and
diameter of internode is 3-6 cm.
Microscopy
Fig. 2: Schematic diagram of transverse section of ephedra stem
Fig. 3: Detailed histological diagram of transverse section of ephedra stem
·
Epidermis:
Single layered, quadrangular cells, with thick and smooth cuticle. Vertical
rows of sunken stomata present between many vertical ridges on the stem.
·
Cortex:
Many layers of thin-walled cellulosic parenchyma. Below epidermis, two or
three layers of loosely arranged palisade like cells are present. Cortex shows
both lignified and unlignified fibers.
i)
Unlignified fibers: like bunch of grapes occur below the ridges where
no palisade cells are present.
ii)
Fibres: Scattered, isolated or in groups of two to four cells lignified.
·
Pericyclic
fibers: lignified, crown the phloem on its outer side
·
Vascular
bundle: Around 10, collateral, conjoint, open and arranged in ring. Contains
phloem and xylem
i)
Phloem: It consists of sieve tubes and companion cells
ii)
Xylem: It is made up of vessels, tracheid’s, parenchyma and fibro tracheids.
·
Pith:
Large, thin walled, lignified parenchyma with intercellular space. Some
cells contain dark brown mucilaginous substance (Brown matter).
Cultivation and
Collection
—
The plant
favors light (sandy) and medium (loamy) soils and requires well-drained soil.
The plant prefers acid, neutral and basic (alkaline) soils.
—
It cannot
grow in the shade. It requires dry or moist soil and can tolerate drought.
—
Seeds are
sown as soon as they are ripe in the autumn in a greenhouse.
—
It can
also be sown in spring in a greenhouse in sandy compost.
—
Seedlings
are transferred into individual pots as soon as they are large enough to handle
and grown them for at least their first winter in a greenhouse.
—
Drug is
collected in autumn since it contains maximum percentage of alkaloids.
—
Green
slender twigs are collected in autumn, dried and packed loose in bags.
Sometimes the twigs are pressed tightly.
Chemical
constituents
— It
contains Amino-alkaloids. Ephedra’s contain about 0.5 – 2.0 % of alkaloids.
— Chief
Constituent: Ephedrine
— Norephedrine
— N-methyl
ephedrine
— Pseudoephedrine
— Root
Contains Macrocyclic alkaloid: Ephedradine
— Oxazolidone
— Tannins
are also found in mostly ephedra species.
— Also
contains flavonoids and polysaccharides.
Chemical test
Ephedrine + Water +
dil.HCl + CuSO4 + NaOH. The solution gives blue colour. If shaken
with solvent ether: Organic
Layer-Purple, Aq. Layer – Blue colour
Therapeutic
Uses
— Ephedra
shows sympathomimetic activity.
— In
allergic conditions like hay fever, bronchitis, Woophing cough.
— To
correct the low BP because of its peripheral contraction of arterioles.
— It
has anti- inflammatory, anticancer, antibacterial, antioxidant properties.
— Pseudoephedrine
is decongestant, cough suppressant and nor-pseudoephedrine is peripheral
vasodilator used to treat angina.
— It
is used as hepatoprotective, anti-obesity and antiviral.
— It
also exhibits diuretic activity.
— Ephedra
is used in the treatment of asthma (Bronchodilator) and hay fever.
— Ephedrine
has more prolonged action than adrenalin as it is slowly hydrolyzed by MAO
and also can be administered by mouth.
— It
has anti-sudorific action.
Substituents and Allied Species
Ephedra
sinica
·
Thickness: 4–7 mm
·
Length: up to 30 cm of branches
·
Leaves: 2–4 mm long, opposite, decussate
and subulate.
·
Leaf, base is reddish-brown, apex acute
and recurved and lamina white in colour.
Ephedra
equisetina
·
Stems are woodier and more branched
·
Length: 25–200 cm of branches and 1–2.5 cm of
internodes,
·
Outer surface: Grey to pale green and
smooth.
Ephedra
nebrodensis
·
Stems are 15–35 cm long; 1–2
mm thick,
·
Cylindrical,
·
Colour: greenish-yellow
·
Nodes are brownish and distinct and
fractured surface is fibrous in the cortex but pith contains brownish powdery
mass.
·
Leaves: Brownish to whitish-brown in
colour, scaly, connate, opposite and decussate, acute, agreeable and slightly
aromatic odour and taste is astringent and bitter.
MULTIPLE CHOICE QUESTIONS (Answers are marked bold)
1. Ephedra gerardiana belongs to which one of the family…………..
(a) Apocyanaceae
(b) Leguminoceae
(c) Liliaceae
(d) Gnetaceae
2. The principal constituent of ephedra is ……
(a) Oxazolidon
(b) Pseudoephedrine
(c) Ephedradine
(d) Ephedrine
3. Characteristics of ephedra leaves include………..
(a) Scale like
(b) Opposite in arrangement
(c) Whorled
(d) All of the above
4. The important features of ephedra stem includes………
(a) Contain longitudinal ridges
(b) Woody
(c) Branched only at once
(d) All of the above
5. Ephedra contains ………..
(a) Amino alkaloids
(b) Tropane alkaloids
(c) Indole alkapoids
(d) Purine alkaloids
6. Ephedra used as……….
(a) Hepatoprotective
(b) Decongestant
(c) Bronchodilator
(d) All of the above
7. …….is one of the important diagnostic features of ephedra powder.
(a) Lignified parenchyma
(b) Cork cell
(c) Calcium oxalate crystal
(d) Brown matter
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