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 stimulate spermatogenesis.
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.
1.2 Aim and Objectives
i. To investigate the effects of ginger (Zingiber officinale) on testosterone.
ii. To investigate the effects of Mucuna urens (Horse-eye beans) on testosterone.
iii. To investigate the combined effects of ginger and Mucuna urens on testosterone.
1.3 Statement of the Problem
Ginger in large doses can cause miscarriage and other complications during pregnancy. Certain experts believe that ginger could cause bleeding due to its anti-platelet (blood thinning) properties. High doses of ginger on the other hand can also aggravate hypertension. An American study reports the occurrence of heat burn in the involved subjects who were given ginger. The most common side effects occur only when it is taken in excessively large amounts. Ginger also stimulates the secretion of bile, which benefit digestion but, if the stomach is empty this can lead to enough gastric stimulation, leading to digestive distress and an upset stomach. Lastly, according to an Iranian study, the most common allergic reaction to ginger is a skin rash, skin redness and skin inflammation.
The most common side effects of Mucuna urens include nausea and a sensation of abdominal bloating, less common side effects include vomiting, abnormal body movements, and insomnia.
1.4 Significance of the Study
The result of this study will increase knowledge to the existing literature about the effect of ethanol seed extract of Mucuna urens and ginger on testosterone.
1.5 Scope of Study
The scope of this study includes:
i. Ethanol extraction of Mucuna urens seed and Zingiber officinale Roscoe
ii Concentration of ethanol extract of Mucuna urens seed and ethanol extract of Zingiber officinal in a water bath.
iii. Determination of acute toxicity (LD50) for Mucuna urens seed extract and Zingiber officinale using mice.