Agriculture Reference
In-Depth Information
and erysothiopine, consistently more active than the free bases;
557
the quaternary bases are, how-
ever, of shorter duration. Other activities of the alkaloids include CNS depression, neuromuscular
blocking, anticonvulsant activity, and hydrocholerectic effects.
428,558,561
EUCALYPTUS GLOBULUS
Botanical Name —
Eucalyptus globulus
Labill.
Synonyms —
Eucalyptus abbreviata
Blakely & Jacobs.,
Eucalyptus acervula
Hook. f.,
Eucalyptus cannonii
R.T. Ba ker
Family —
Myrtaceae
Common Names —
Eucalyptus leaf, blue gum tree (E), eucalyptus (F)
African Names —
Arabic: kafur; Hausa: Igbo: nkwu-ishi; Swahili: mti- ulaya
Description —
They are very tall trees with straight trunks that often have white peeling bark;
sometimes, they attain a height of up to 100 m. The leaves are orbicular, with a bluish or silvery
surface, and exude a fragrance when crushed; they measure about 230 cm in length and 4 cm in
width and are ensiform, acute, entire, coriaceous, brittle, and punctate. The inflorescence is umbel-
late with white flowers. The plant produces capsular fruits. It has an agreeable and aromatic odor,
and the taste is aromatic, pungent, and slightly bitter.
Habitat and Distribution —
This is a subtropical plant that originated from New South Wales
and Queensland but was introduced in Africa as a cultivated crop. This and related species, such as
E. citriodora, E. divans,
and
Eismithii,
are cultivated in many parts of the continent, especially in
well-drained subtropical and Mediterranean regions.
Ethnomedicinal Uses —
The leaves of
Eucalyptus
are employed as a remedy for colds. They
are also ingredients in the potherb used as steam therapy for malaria.
Constituents —
The plant contains up to 3% volatile oil, the major constituents of which are
cineole, together with tannin, a bitter principle, and resin. The oil also contains (+)-a-pinene, phel-
landrene, geraniol, alkyl aldehydes, methyl cinnamate, and a variety of terpenes.
Pharmacological Studies —
The essential oil has been found to possess antimicrobial (includ-
ing antitubercular) activity.
559,560
The plant is listed in the
Martindale Extra Pharmacopoeia
for
catarrh and as a rubefacient.
205
Toxicity —
Side effects of excessive eucalyptus consumption include nausea, vomiting, diz-
ziness, muscular weakness, and a feeling of suffocation. Fatality due to severe poisoning is
known.
205
EUPHORBIA (MILKWEEDS)
Three species of
Euphorbia
are common in Nigeria:
E. desmondi
and
E. kamerunica,
which
are medium-size trees, and
E. hirta,
a small herb. Other species are described in specialized text-
books of economic botany; they include
E. aegyptiaca, E. balsamifera, E. convolvuloides,
and
E.
lateriflora.
The three species mentioned first are all considered important, but
E. hirta
is by far
the most widely used in the preparation of traditional remedies. There is little problem in differen-
tiating
E. hirta
from the other two species, although
E. hirta
is practically indistinguishable from
E. convolvuloides.
Since in traditional medicine both plants are not distinguished in their use,
the drug euphorbia
should apply to both
E. hirta
and
E. convolvuloides.
All the species produce
irritant milky sap.
