Ethnobotanical survey and phyto-anatomical studies of some common plants used for the treatment of epilepsy in some rural areas of South west Nigeria

Aim: To survey some areas in the southwest Nigeria where epilepsy is treated with plant extracts and determine the commonest plant species that are used, for pharmacognostic analysis. Materials and Methods: Open-ended and semi-structured interviews were conducted for information from traditional medicine practitioners. Plant names given were authenticated in the herbarium and phytochemical and anatomical analyses were conducted on the plant parts that are used for treatment using standard approaches. Results: Fifty practitioners were interviewed and they gave 17 different plants; out of these, the 5 commonest ones were investigated. The plants are either used individually or in combination with other plant(s). Services may be rendered freely or by collecting a token which is supernaturally believed to have negative consequences. The practitioners engaged in out-patient and in-patient services and patients are usually totally cured. There are also some inexplicable practices such as oracle visitation, incantations etc. A total of 30 patients have been cured in the last decade by each practitioner. Saponin, steroids, tannins, flavonoids, phlobatannins and alkaloids were isolated using three different media (methanol, petroleum ether and water) and diagnostic anatomical characters of the leaf epidermis, fruit wall, bark and root of the plants are presented in a single account for the first time in the country. The plants studied were Newbouldia laevis, Securidaca longipedunculata, Tetrapleura tetraptera, Nicotiana tabacum and Senna occidentalis. Conclusion: The phytochemicals found are suggestive of the underlying medicinal potency of the plants and future work will help to establish the most active principles which will lead to development of drugs for treating the disease. The diagnostic anatomical characters can be employed in resolving doubts especially when the plant materials are in fragments. The least mentioned plant species can be saved from harvesting to conserve the rich flora diversity in the country.

Key words: Epilepsy, phytochemistry, plant anatomy, south-west Nigeria, tropical forest.