title: Anti-trypanosomal activity of African medicinal plants: a review update.
abstract: BACKGROUND
  African trypanosomiasis is one of the neglected tropical diseases caused by different species of trypanosomes that affect both human and livestock with devastating consequences in the continent. Most of the affected populations commonly use traditional medicinal plants for the treatment of the disease. Consequently, this prompted ethnopharmacological research activities on the anti-trypanosomal activity of a number of these African medicinal plants in order to validate their ethnomedicinal use. Furthermore, such studies could lead to the identification of chemical leads for the development of newer anti-trypanosomal agents from those plants. This review aims to provide updated information on the ethnopharmacological evidence of African medicinal plants with anti-trypanosomal activity.
  
  
  METHODS
  Literature was collected via electronic search (PubMed, Sciencedirect, Medline and Google Scholar) from published articles that report on the in vitro or in vivo anti-trypanosomal activity of plants that were collected from different parts of Africa.
  
  
  RESULTS
  African medicinal plants investigated for in vitro and in vivo anti-trypanosomal activity from January 1993 to October 2013 are systematically compiled and all the in vivo studies are critically discussed. A total of 264 plant species belonging to 79 families were investigated for anti-trypanosomal activity. However, only 48 bioactive anti-trypanosomal compounds were successfully isolated in pure forms. Furthermore, some of the plants were investigated for possible ameliorative effects on the trypanosome-induced pathological changes out of which 18 plants were reported to be effective while a few others were not. In spite of interesting preclinical ethnopharmacological evidence for anti-trypanosomal activity, not a single African medicinal plant was investigated in a clinical study.
  
  
  CONCLUSIONS
  Several African medicinal plants have demonstrated promising anti-trypanosomal effects but the studies on the anti-trypanosomal potentials of these plants are not taken beyond proof of concept stage. It is hoped that the article would stimulate future clinical studies because of the paucity of knowledge in this area.
authors.affiliation: Department of Biochemistry, Ahmadu Bello University, Zaria, Nigeria. Electronic address: mauwalibrahim@gmail.com.
authors.forename: Mohammed Auwal
authors.initials: MA
authors.lastname: Ibrahim
authors.affiliation: Department of Biochemistry, Ahmadu Bello University, Zaria, Nigeria.
authors.forename: Aminu
authors.initials: A
authors.lastname: Mohammed
authors.affiliation: Department of Biochemistry, Umaru Musa Yaradua University, Katsina, Nigeria.
authors.forename: Murtala Bindawa
authors.initials: MB
authors.lastname: Isah
authors.affiliation: Department of Chemistry, Ahmadu Bello University, Zaria, Nigeria.
authors.forename: Abubakar Babando
authors.initials: AB
authors.lastname: Aliyu
mesh_terms: D000818:Animals; D016488:Medicine, African Traditional; D010946:Plants, Medicinal; D014344:Trypanocidal Agents / Q000494:pharmacology*; D014345:Trypanosoma / Q000187:drug effects
chemical_list: D014344:Trypanocidal Agents
keywords: Africa; Anti-trypanosomal activity; Medicinal plants; Trypanosoma brucei