Agriculture Reference
In-Depth Information
Synonyms —
Chirocalyx latifolius
Wa lp.,
Duchassaingia senegalensis
( DC.) Hassk.
Family —
Leguminosae
Common Names —
Coral flower, parrot tree
African Names —
Bini: eranigbonyakehi; Efik: edeng; Hausa: majiriya; Igbo: echichi; Masai:
al oboni; Ndebele: umkawana, ummpumbuluku; Shona: munyanyudza; Yoruba; ologun sheshe;
Tiv: showoh
Description —
Erythrina senegalensis
is a medium-size shrubby tree, 3-4.5 m high but some-
times growing up to 15 m in height and 1.5 m in girth, and prickly. The bark is very rough and is-
sured, becoming remarkably so in old trees. It has crooked branches with an irregular crown; the
thorns on the old wood are slightly curved, with thick woody bases. The slash is yellowish, turning
brown on exposure to air. The leaves are rather variable in shape and size, with three leaflets 15 ×
10 cm, with the central leaflet the largest. They are usually lanceolate to broadly ovate, glabrous,
and sometimes with prickles on the midrib. The flowers are produced September-January in slen-
der racemes up to 30 cm long and scarlet, but they turn black over time. The petals are about 2.5-5
cm long, and when leafless, are folded very flat so that the stamens are hidden. The pods are about
12 cm long and irregularly constricted but usually between seeds; the seeds are red, glossy, with a
white hilium about 0.6 cm long.
8,28,33
Habitat and Distribution —
The species is a common savanna tree, occurring on the banks
of streams and sometimes planted for its medicinal properties. It is distributed from Senegal to
Cameroon and also grows in Kenya, Tanzania, Zimbabwe, and Ethiopia.
Ethnomedicinal Uses —
The root infusion is used in Nigeria as a toothache remedy and in the
Ivory Coast for venereal diseases. The stem bark is employed extensively in traditional medicine,
and several trees in homesteads are often stripped of the barks. The aqueous extract of the bark is
used for the treatment of jaundice in northern Nigeria; an infusion mixed with lime and pepper is
administered for venereal diseases. A decoction of the bark has been used for the treatment of bron-
chial infections, coughs, and throat inflammation. The pounded bark and leaves are used in soups
to treat female infertility. Extract of the bark is given to women during childbirth; in Guinea, it is
administered after delivery, whereas in Nigeria it is given to women during labor to ease pain. The
wood is reputed to be an aphrodisiac. In central Africa, infusion of the bark and roots is used as an
enema for fevers, inflammation, and stomachache.
Constituents —
The plant yields alkaloids with curariform activity, collectively known as
Erythrina
alkaloids. The major ones include α- and β-erythroidine, erysodine, erysovine, erysotrine,
and erysopine. Over 30 alkaloids have been recorded from the genus, and in
E. senengalensis
, ery-
sodine represents 50% of the total alkaloids.
78,554
Pharmacological Studies —
The
Erythrina
alkaloids have been extensively evaluated for their
curarizing effects. Earlier studies showed that, based on grams of frog curarized per gram of seed,
the species has a value of 20,000 versus 44,000 IU for the related
E. sigmoidea
.
555
The alkaloids,
which have the advantage of being active when taken orally, have been found useful as muscle
relaxants in a number of clinical applications, such as for the control of convulsions; as an adjunct
to general anesthesia, especially to relax muscles of the abdominal wall; and in electroconvulsive
t herapy.
428,556
The mechanism of action of the
Erythrina
alkaloids is similar to that of curare, the
paralyzing effect being due to synaptic blockage of the nervous impulse traveling toward the skel-
etal muscle, without CNS involvement. Unlike curare, which is excreted in the urine, alkaloids
of
Erythrina
are excreted in various ways, and the paralyzing effect is useful in various surgical
procedures in which temporary muscular relaxation is required. β-Erythroidine has been shown to
compete with acetylcholine, and its curare-like effect is inhibited if quaternization of the nitrogen
in its molecule is modified.
It has been shown that a relationship exists between the structure of
Erythrina
alkaloids and their
biological activities, with the sulfoacetic esters of erysovine and erysopine, as well as erysothiovine
