Aside from servingas a main source of food and nutrition, plants have long been exploited as amajor source of medicine in most parts of the world. According to WHO, eighty-fivepercent of the world’s population, mostly those in developing countries,depends on plants for medicine and at least twenty-five percent of prescriptiondrugs have an active ingredient derived from a plant or herb1. These Herbalmedicines are used to treat a variety of ailments such as dysentery,cardiovascular diseases, infertility and asthma. One such plant that is used medicinally is Xylopia aethiopica.
This herb is an important plant intraditional west African culture and researchers are currently seeking toinvestigate its many medicinal properties and their effects on an array ofhealth care issues.Xylopia aethiopicacommonly known as Negro pepper or in Nigeria as Uda by the Igbo tribe, Chimbaby the Hausa tribe and Eeru alamo by the Yoruba tribe is a tall evergreenaromatic tree belonging to the Annonaceae family. Although this plant was firstdiscovered in Ethiopia, it is mostly grown and prominent through out WestAfrica especially in Ghana. The fruit ofthis plant is used as a spice or condiment in many traditional African dishessuch as stews, meats, and sauces. Apart from its culinary benefits, X. aethiopica also possess a wide arrayof uses in traditional African medicine.
Negro pepper is said to contain chemical constituents such asflavonoids, alkaloids, cineol, phytosterols, tannins, saponins, glycosides,carbohydrates, ?-pinene, paradol, ?-terpineol, terpinene-4-ol, terpenes,cryptone, verbenone, ?-phellandrene, spathulenol, bisabolene,trans-pinocarveol, limonene, linalool, and myrtenol.2 Due to these varying chemical constituents and their varyingproperties and functions, X. aethiopicais frequently used in decoction tomake tonics that aid in childbirth as well as treat a plethora of ailments includingbut not limited to, cancer, bronchitis, diabetes mellitus, skin infection, maleand female fertility. According to the Americancancer society, one in seven men will be diagnosed with prostate cancer in hislifetime. Additionally, in 2017 there was about 161,360 new cases of prostatecancer diagnosed.3 Conversely, according to the world cancerresearch fund international one in eight women will be diagnosed with breastcancer in her lifetime and there were 1.
7 million new cases diagnosed in 2017.4Given the high prevalence and mortality rate of cancer and the lack of accessto modern medication and adequate healthcare in Nigeria, identifying low costand effective ways for optimal treatment is of the utmost importance. To thisend, researchers in Nigeria conducted a preliminary study investigating the anti-proliferativeeffects of X. aethiopica on cell linesof breast and prostate cancer in vitro. The researchers extracted ethanolicacid from the fruit of the Negro pepper plant and tested it, in vitro, againstprostate cancer (LNCaP) and breast cancer (MDA-MB231andMCF7) celllines. The results from this study showed a dose-dependent anti-proliferative activity against LNCaP,MDA-MB231and MCF7 cell lines after treatment for 48 and 72 hours. According tothe researchers, the extract induced a 16.96 per cent and 93.
5 per centinhibition on MDA-MB231 cells, 29.76 per cent and 94.03 per cent on the MCF7cells and a 9.15 per cent and 94.61 per cent inhibition on the LNCaP cells atthe lowest (1?g/ml)and highest (100?g/ml) dose respectively after 48 hours. Moreover, after 72 hoursTheextract induced a 12.26 per cent and 91.
8 per cent cell growth inhibition onthe MDA-MB231 cells, 3.35 per cent and 87.36 per cent growth inhibition on theMCF7 cells and 2.28 per cent and 92.42 per cent cell growth inhibition on theLNCaP cells at the lowest (1?g/ml) and highest (100?g/ml) doses respectively.5These findings demonstrating the growth inhibition in the cancer cell lines indicatethat X. aethiopica has someanti-proliferative effects on prostate and breast cancer cells lines. Theaforementioned findings also highlight the usefulness of this plant and the need for moreresearch that will further investigate the mechanism of action of this pepperas well as the potential for the development of new cancer interventions thatcan work in conjunction with other conventional cancer treatments orinterventions that can be used independently to target these specific cancers.
Aside from cancerresearch, scientist have researched the use of X. aethiopica on other aspects of health such as contraception. Goldstandard contraceptive techniques have varying side effects ranging from weightgain to blood clots.
For this reason, it is worthwhile to explore the use andefficacy of herbs and other natural products as alternatives to conventionalmedication. According to H.M. Burkill6 in, “The useful plants ofwest tropical Africa”, X. aethiopicahas been used for centuries as an effective natural contraceptive. This herb isbelieved to cause temporary adverse effects on the reproductive system of men. Woodeet al7 conducted a research study evaluating the effects of Xylopicacid, a kaurane derivative extracted from the plant, on serum sex hormones andspermatogenesis in male rats. The Xylopic acid was administered orally to themice at varying doses (10, 30, 100 mg) over a 28 day period.
Blood samples werecollected at the 7 day and 28 day period. Xylopic acid was shown to cause adecrease in sperm count, motility and viability. Furthermore, the resultsshowed a significant decrease in serum testosterone levels at 28 days as wellas damage to the seminiferous tubules of the male mice. Normal seminiferoustubules cells and serum levels returned 2 weeks after use was discontinued.Therefore, it can be hypothesized that X.aethiopica’s primary mechanism of action as a contraceptive is throughXylopic acid and this acid may work primarily by directly disrupting thefunction of cells in the testes that are primarily used to make spermatocytesand androgens. Ultimately, the temporary antifertility properties that X.
aethiopica possess is evidence thatthis herb can be an effective and viable alternative contraceptive method.However, more research needs to be conducted into the effects of this inHumans.X. aethiopicaalso has abortifacient properties that are exploited to aid with child birthand menstrual problems. In eastern Nigeria, the Igbo tribe traditionally use X. aethiopica in addition to othermedicinal plants to make a postpartum herbal tonic. This tonic is said to helpto clear blood clots in the womb and to aid in placental discharge afterchildbirth.
Unknown chemicals in this herb causes the smooth muscle of theuterine lining to contract consequently causing shedding of the uterine lining.This mode of action of this herb is said to also aid in stimulating menstrualflow in those with irregular menstrual cycles or amenorrhea. Additionally, whentrying to induce labor, this same mode of action can be exploited when X. aethiopica is taken in small doses,although there is not a wealth of information on an exact safe dose or how safethis herb is for the mother or the fetus. Despite the supposed positivemedicinal effects of X.
aethiopica use,a research study conducted on albino rats by Obembe et al8 revealeda potentially serious negative side effect associated with the use of thisherb. The results from the study showed a significant dose dependent (100 mg/kgbody weight and 200 mg/kg per body weight) decrease in hemoglobin, white bloodcells and mean corpuscular hemoglobin concentration at 28 days of continuousingestion. Additionally, usage during this 28 day period was shown to disruptclotting factors therefore prolonging bleeding time irrespective of dosage.Given this information, individuals should be mindful of this side effect whenconsuming or using this herb medicinally. Appropriately, given theinformation from the aforementioned animal and in vitro studies, X.
aethiopica is shown to have greatpotential medicinally in the treatment of various ailments and conditionseven though there is not a wealth of published data on the use of this herb inhumans. It is important to continue to conduct research into the uses of X. aethiopica to ascertain its safetyand efficacy in humans as this herb may prove to be a great alternative and/ orgreat adjuvant to modern medication.