The effects of
ethanol extract of Ginger and Horse eye bean on testosterone of male albino
wistar rats were investigated. Fifty male albino rats weighing 120g – 200g were
divided into 10 groups with 5 animals in each group. Group I served as the
control while Groups 2,3,4,5,6,7,8,9,10 were the experimental groups. 600 seeds
of Mucana urens and 200 rhizome of Zingiber officinale were used. The content was
extracted using 2000mls and 1000mls of ethanol for Mucuna urens and Zingiber
officinale. Filtered and concentrated in water bath at 45oc. 1000mg of the
extracts were dissolved in 10mls distill water. The extracts were administered
orally for twenty-one days. Group 1 was administered 5mls water, group 2 was
administered, 500mg/kg Mucuna urens, group 3 was administered 1000mg/kg Mucuna
urens, group 4 was administered 1500mg/kg Mucuna urens, group 5 was
administered 86.6mg/kg Ginger, group 6 was administered 173.21mg/kg Ginger,
group 7 was administered 259.81 mg/kg ginger, group 8 was administered 500mg/kg
MU + 173.21 mg/kg 20 and group 10 was 1500mg/kg + 259.81mg/kg ZO. Data were
analyzed using one-way ANOVA (p<0.05). Ethanol seed extract of Mu decreased
testosterone levels and ZO extract increases testosterone levels.
1.1 BACKGROUND OF THE STUDY
Ginger is a spice
originated from the Rhizomes of the plant Zingiber officinale. It is valued around the world as an important
cooking spice. Ginger is available fresh
and dried, as ginger extract and ginger oil and in tinctures, capsules and
lozenges. The plant is a rhizome that
has been used in traditional medicine to aid nausea, diarrhea, arthritis,
digestion and treat stomach upset for centuries. Ginger is also believed to
help the flu-like symptoms, headaches and even heart disease (Bhandari et al.,
1998) or cancer (Katiyar et al, 1996).
The important active components of the ginger root are thought to be
volatile oils and pungent phenol compounds such as gingerols, shogaols,
zingerone and gingerous (Sekiwa et al, 2000; Zancar et al, 2002).
Young ginger rhizomes are juicy and
fleshy with a mild taste. They can be
steeped in boiling water to make ginger herb tea. Mature ginger rhizomes are fibrous and nearly
dry. It is also medically used for its
immunomodulatory, anti-tunorigenic, anti-inflammatory, antiapoptotic and
antioxidant properties. In addition, it was found that Zingiber officinale is
associated with a beneficial effect on male reproductive functions in rats,
which confirmed by other studies on the increased sperm counts, motility,
testosterone and decreased malonhydialdehyde levels. It was also observed that the administration
of ginger can significantly increase testosterone level, in plasma and
Although the effectiveness of ginger
as an antioxidant agent has been exploited in animals, little human research
has been conducted on its activity on male reproductive functions.
Mucuna urens is a plant that belongs
to the family fabaceae, commonly found in home gardens in the south eastern
parts of Nigeria, West Africa, where the Efik’s, Ibibio’s and Igbo’s use the
seeds as a major soup condiment for thickening.
In Northern Nigeria, farmers incorporate the seed into the normal feed
for farm animals due to its rich protein content (Umoren et al, 2007). It is called “Ibaba” by the Efik/Ibibio’s and
“ukpor” by the Igbo’s and is usually sold in the local markets during its
harvest season which is in the month of January (Eilitta and Carsky, 2003),
though in recent times, it is cultivated near trees as support for growth to
enable production of many seeds per plant (Sridhar and Bhat, 2007). In other localities where Mucuna urens is
found, it is known as velvet bean, pica-pica, being nutritionally (Esonu et
al., 2001). Despite being nutritionally
promising, Mucuna has been reported to contain some endogenous toxic factors. Relatively high concentration of tannins, phytic
acid, cyancgenic glucoside, oxalate and gossypol have been reported in mucuna
(Laurena et al, 1994).
Toxic compounds including L-DOPA (3,
4 dihydroxy-L-phenylalanine), nicotine, physostigmine and serotinine have been
also reported in mucuna. These factors
negatively affect the nutritive value of the beans through direct and indirect
reactions; they inhibit proteins and carbohydrate digestibility; induce
pathological changes in the intestine and liver tissues, thus affecting
metabolism; inhibit a number of enzymes and bind nutrients, thus making them
unavailable (Bressani, 1993). It is
however, believed that heat treatment reduce these anti-nutritional properties
of the seeds (Umoren et al, 2007). There
are reports that the seed affect the consistency of semen and motility of sperm
cells (Udoh and Ekpenyong, 2001).
Mucuna urens is often
cracked and removed from the seed coats soaked in water and then boiled
(Osei-Bonsu et al.,1995; Elitta and Carsky, 2003), roasted or fermented to
remove most of the toxic substances, which have been implicated in poisoning
(Ose-Bonsu et al., 1995).
Horse eye bean are
reported to be rich sources of potassium, magnesium, calcium, iron, protein and
amino acids (Olaboro, 1993) as well as containing 5-hydrotryptamine, mucunine,
mucunadine proteins, carbohydrates, tannins and phytates (Udoh and Ekpenyong, 2001).
Udoh and Ekpenyong
(2001) also reported the degeneration of sperm in testicular tubules, collapse
of the villi in prostate gland and reduction of secretion in the prostate gland
and seminal vesicles of male guinea pigs treated with seeds of horse eye-bean. Horse eye bean, ox-eye bean and devil bean
are the common English name for Mucuna urens.
Infertility is the
inability to conceive after having unprotected sex for the period of 12
months. About 20 to 30% of infertility
cases are due to male infertility and 20 to 35 are due to female infertility.
25 to 40% are due to combined problems in both parts.
In about 10 to 20% of
cases, no cause is found, male infertility is most commonly due to deficiencies
in the semen, and semen quality is used as a surrogate measure of male
fecundity. (Cooper et al, 2010). Factors relating to male infertility include
Immune infertility, testicular factors, variocele, age, genetic defects on the
Y choromosome and abnormal set of chromosomes.