Willis (1973) classified Garcinia kola (Heckel) taxonomically
as follows:-
Kingdom
: plant ordor . Guttiferales.
Family:
Guttiferales . sub -family clusiudeae
Tribe:
Garcinieae: Garcinia
Species:
Kola
Botanical
name: Garcinia Kola (Heckel)
Common
name: Bitter Kola
Local
name:
Igbo
: Agbi-ilu, Aki-ilu
Yoruba:
Orobo
Ibibio:
Efiat
Efik:Efiari
Bini:
Edun
Hausa:
Namijin gor
HISTORY
The seeds of several
plants have been used either
wholly as a substitute for, or as
adulterants of, true kola. All of these, however, lack
the characteristic principles of the true kola. Among these plants
is Garinia Kola (Heckel). The fruit of
this plant is rarely found as an adulterant
of kola, as their external features are entirely different. However,
it bears the name of false kola, male kola, and bitter kola. It is
highly esteemed by the native of Africa, though devoid of marked stimulant
properties of true kola. Negroes
chewed it as a powerful aphrodisiac and,
as masticatory, they employ them in
common colds. They contain tannin, colour matter, and a brown and a yellowish-
white resin but no alkaloids (Harvey
Wickes, 1898).
The flowers of Garcinia kola are greenish white, with reddish
hair on both the sepals and petals. The flowers have very short
stalk, while its ovaries are hairy and the stigmas are four lobed. The
fruits is reddish-yellow, about 6.25cm in diameter, and each fruit
contains two to four brown seeds embedded in orange- coloured pulp (Atilad Akanmu 1997 pg 121). Garinia species
is a wide forest tree, height varies considerable but can grow up to
30m.
Garcinia kola is endemic in the humid lowland
rainforest vegetation of the west and central African subregions. It is found in
coastal areas and lowland plains up to
300m above sea level with an average of 2, 500mm of rainfall per annum. The
trees are abundant in densely
populated areas of natural and secondary forests where the predominant
land use system is tree crop plantation farming
(Aiyelagbe and Adeola 1993). Temperature ranges from 32.150C
to 21.40C and a minimum relative humidity of 76.343% (Atilad Akanmu
1997 pg 117).
An important and ancient trade product, the nuts of Garcinia kola are
available in markets throughout west and
central Africa, from Senega town
in Sierra Leone to South-West Cameroon (Atilad Akanmu 1997 pg 116). In Nigeria,
its trade is as important as that of kolanut in major towns and cities in the
Southern parts of the country, where the
tree is endemic. It is favoured by the three major ethnic groups in Nigeria, the yorubas, Igbos
and Hausas. Its domestic trade thus
extends beyond the Southern production areas
to the Northern parts of the country.
GERMINATION
There is long gestation period before
flowering and fruiting. However, many of the germinating difficulties have been overcome by methods
developed by (Okafor 1998, Atilad Akanmu
1997 pg 121), and interest is developing
to cultivate the tree species
in plantations. CULTIVATION
They require temperature range from
32.150C to 21.40C and a minimum relative humidity of
76.34% (Atilad Akanmu 1997 pg 117). The seed is raise in nurseries. Fruiting in
the tree commences in July and ends in October.
Fruit harvest continues intermittently as ripe fruit fall and are
then collected for the extraction of seeds.
STORAGE
When
ripe, the green pericarp turns to a reddish yellow colour, and the fruit falls from the tree. The fruit are collected and kept in an open, cool
place till the pericarp and the pulpy musocarp become soft. Once softened,
the fruits are threshed to
released the nuts, which are thoroughly washed to remove sticky mucilaginous
material that sheaths the nut. Nuts that are not sold fresh are
then spread out and air- dried in preparation for storage, which is
provided by wrapping the nuts in leaves and storing them in a basket lined with jute bag materials. This process is repeated as fruits ripens and is collected throughout the harvesting period.
CHEMICAL
HISTORY AND COMPOSITION
The constituents of Garcinia kola include: biflavonoids
xanthones and benzophenones. The
antimicrobial properties of this
plant
are attributed to the benzophenone, flavanones (Iwu, 1993). Dimethylamine, methylamine, ethylamine and
Isopentylamine in three varieties
of kola nut, cola acuminates, C. nitida and Garcinia cola (Atawodi; 1995) , Lipid
composition of the seeds of Garcinia Kola, Chrysophyllum
albidum, and Dennettia tripelattia range from 32-69 gm/kg (Akintonwa A, and A.R.
Essien, 1995). The biflavanones GB1, GB2 and kolaflavanone
were isolated as the active constituents (Iwu 1985).
ACTION,
MEDICAL USES AND DOSAGE
Medicinal uses of Garcinia kola, include purgative, antiparasitic, antimicrobal . The
seeds are used in the treatment of
bronchitis and throat infections. They are also used to prevent and relieve colic, cure head or chest colds
and relieve cough. Also the plant
is used for the treatment of liver disorders and as a chewing
stick (Iwu 1993). Studies show very
good antmicrobial and antiviral properties.
In addition, the plant possesses antidiabetic;
and antihepatotoxic activities (Iwe
1993).
Garcinia
kola seeds are considered a poison antidote in Africa. Kolaviron at 100mg/kg orally reduced thiopental-
induced sleep in CCL4- poisoned rats and
protected microsomal enzymes against
phalloodin (Iwu 1987). Paracetamol-
induced hepatotoxicity in rats was
reduced by Garcinia kola seed extract. Protection might be due to inhibiting P-450 activation of the toxin
(Akintonwa 1990). Blood sugar was lowered
from 115mg/dL to 65mg/dL by Kolaviron, a mixture of C-3/C-8 linked
biflavonoids obtained from Garcinia
kola, at 100mg/kg in rabbits. It
also inhibited rate lens aldose reductase IC50 =5.4 x10(-6) (Iwu
1990). Lipid peroxidation of rat liver
was inhibited by G.Kola in a dose dependent manner; possibly due to isoflavones
(Adegoke, 1998).
