Agriculture Reference
In-Depth Information
Common Names —
Fenugreek (E), fenugrec (F)
African Name —
Arabic: helba
Description —
Trigonella foenum-graecum
is an erect herbaceous annual, 10-40 cm tall, aro-
matic, smooth. It has compound leaves 7-12 cm long. The flowers are whitish or purplish blue,
blossoming solitarily or in groups of 2. The fruits occur as 2-10 cm pods that are long, thin, and
pointed and contain 10-20 seeds.
Habitat and Distribution —
It is found in temperate and Mediterranean regions of Africa. It
occurs in Egypt, northern Sudan, Libya, and Tunisia. The plant is cultivated on a small scale in the
Jos plateau of Nigeria and in the Rift valley of East Africa.
Ethnomedicinal Uses —
In North Africa, the seeds are used as an oral antidiabetic. The plant
is used as a galactagogue in the Sudan.
1043
The leaves are used in various folk remedies for the relief
of indigestion and general stomach disorders. The seeds are edible and have been used in remedies
for rheumatism, chronic cough, and enlargement of the spleen and liver and as a general tonic.
Extracts of the seeds are incorporated into several cosmetics claimed to have an effect on premature
hair loss and as skin cleanser.
Constituents —
The seeds contain trigonelline (
N-
methylnicotinic acid), choline, nicotinic
acid, and diosgenin. Essential oil, mucilage, and fixed oil are also major components of the seeds.
Fenugreek has been shown to be a feasible source of diosgenin, which occurs in the embryo of the
seeds
1044,1045
before acid hydrolysis improves the sapogenin yield.
1046,1047
It contains amino acids,
and 4-hydroxyisoleucine (4-HI) constitutes about 80% of the total content of free amino acids in
Trigonella foenum-graecum
seeds.
Pharmacological Studies —
A 2% concentration of the saponin fraction showed
in vitro
sper-
micidal action against rat and human semen.
1048
The alkaloid trigonelline has been shown to coun-
teract the hyperglycemic effect of cortisone given 2 h before or simultaneously.
78
Nicotinic acid
and coumarin, which co-occur in the plant, are also hypoglycemic. The compound was moderately
effective in alloxan diabetic rats and in human subjects.
1049-1051
Fenugreek has been shown to possess antidepressant activity, which has been attributed to the
hydroxyisoleucine content. It was found that oral acute administration of 4-HI showed the dose-
dependent reversal in forced swim-induced increased immobility behavior in normal and reserpin-
ized mice in the dose range of 3 to 30 mg/kg; the spontaneous motor activity (SMA) scores were
not affected by 4-HI in normal or reserpinized mice except for the dose of 30 mg/kg, which showed
a central rather than peripheral mechanism of 4-HI; a significant increase in the number of 5-HTP
(precursor of serotonin) -induced head twitches was shown by 4-HI. In conclusion, 4-HI showed
antidepressant-like effects in animal models of depression by brain serotonin turnover enhance-
ment.
1052
4-HI has also been found to possess antidyslipidemic and antihyperglycemic activities. It
significantly decreased the plasma triglyceride levels by 33% (
p
< 0.002), total cholesterol by 22%
(
p
< 0.02), and free fatty acids by 14%, accompanied by an increase in HDL-C/total cholesterol
ratio by 39% in the dyslipidemic hamster model.
1053
The plant has immunomodulatory, gastrointestinal protective, antioxidant, and AChEI activi-
ties, and these effects make fenugreek a very valuable herbal medicine and dietary supplement.
UNCARIA GAMBIER
Botanical Name —
Uncaria gambier
Roxb.
Synonyms —
Umcaria qabir
Roxb.,
Nauclea gambir
Hunt.
Family —
Rubiacea
Common Names —
Pale cathecu (E), gambier (f)
African Names —
Arabic: qafir hindi, fufal hindi
