Warburgia ugandensis – family Canellaceae – is also known as the ‘Uganda Green Heart Tree’. This evergreen tree is a dominant species in Uganda, Kenya and in some parts of Ethiopia. It is considered an integral part of African traditional medicine by many traditional healers or herbalists across the continent.
The tree can grow to 5-30 mtr tall and 70 cm in diameter at breast height. Its bark is scaly with pale green to brown colour while its leaves are alternate, simple, dotted with petiole that are 1-5 mtr long. The flowers are small 3-4 flowered cymes with white or greenish-yellow colour. The fruits are berries that are first green when young that later turn purplish with a size of about 3-5 cm in diameter as they mature. The seeds are two or more with oily endosperms that are yellow-brown in colour and about 1.0-1.5 cm long. Warbugia ugandensis is propagated by stem cutting and also by seeds. Since it is a wild tree species, the saplings in most cases are protected from within their natural habitats or transferred to the farms for more intense management.
Warbugia ugandensis is considered an integral part of African traditional medicine by many traditional healers or herbalists across the continent. All the plant parts of Warburgia ugandensis are used by the herbalists in traditional medicine to treat a number of health conditions. Although the bark is the most often used part for the various herbal formulations, the leaves and roots are also highly medicinal.
In African traditional medicine, the bark of Warburgia ugandensis is boiled with water to make a decoction or infusion which is taken orally to treat a myriad of diseases ranging from stomach ache to epilepsy to erectile dysfunction to skin infections and malaria. Patients are advised to chew the bark and swallow its juice for the treatment of constipation, venereal diseases, cough, fever, weak joints and general body pains. Just a pinch of bark powder mixed with a spoonful of water taken orally at a prescribed interval can treat dry cough. Patients can also rub the powdered bark of Warburgia ugandensis to the temple of the head to treat headaches. The stem bark of Warburgia ugandensis is also powdered and added to porridge to prevent and treat gastric ulcers.
In some instances, the bark of Warburgia ugandensis is taken as tea to manage epilepsy while the powdered dry bark can be added to milk and soups and, when taken orally to manage viral infections in the body like flu and influenza virus. In some cultures for example, among the Maasai pastoralists of Kenya, the scraped bark of Warburgia ugandensis is soaked in milk or water and taken orally to treat tuberculosis.
The leaves are boiled with bathing water to treat skin conditions such as scabies, ring worms, and fungal infections among others. A mixture of leaves and stem barks of Warburgia ugandensis boiled with water are culturally used to treat asthma and bronchitis, while the powdered root is applied to cavities in the teeth for treatment of toothache. Similarly, a mixture of the leaves, bark and roots is boiled with water to prepare a decoction that is taken orally to treat and prevent diarrhea, malaria, chest pains, worm infections and headaches. However, high dosages of this mixture have been reported to induce vomiting in patients. Apart from boiling with water or adding in milk and soup, there are other alternative modes of preparation and administration of Warburgia ugandensis to patients, such as smoke snuffing. In smoke snuffing, the plant part is burnt in a room and the patient must inhale the smoke coming out of the fire at prescribed intervals to cure a given condition.
Scientific studies show that Warbugia ugandensis is rich in bioactive compounds like alkaloids, sterol, triterpenes, flavanoids, cardiac glycoside, saponins and tannins that have antimicrobial activity. Its use in the treatment of infectious diseases is associated with these bioactive compounds. Its bitter taste is also attributed to the presence of alkaloid bioactive compound in the plant.
Since it is often the bark or the roots of Warburgia ugandensis that are used for their curative or medicinal properties, a steady decline in the wild populations is emerging in African countries due to over harvesting and the use of destructive harvesting techniques of the bark and roots. Consequently, this important medicinal tree is now listed on the International Union for Conservation of Nature (IUCN) red list and categorised as a species vulnerable to extinction. Currently, people are encouraged to establish private commercial plantations of Warburgia ugandensis to prevent over exploitation of the wild population.
In conclusion, Warburgia ugandensis has an illustrious history in African traditional medicine for a variety of health condition and the traditional healers regard products from this plant very highly. Indeed Warburgia ugandensis is described as a miraculous plant in a wide range of communities across Africa.
– Komakech Richard & Omujal Francis
