Extension of the EU "Traditional Herbal Medicine" concept to an oral transmission context: the traditional uses of the five anti-infectious medicinal plants most widely used in Burundi

Abstract

Background: In Burundi, five plants, namely Urtica massaica Mildbr., Mikania natalensis DC., Senecio maranguensis O. Hoffm., Justicia nyassana Lindau and Helichrysum congolanum Schltr. & O. Hoffm., are widely cited for the treatment of infectious diseases. The present work aims to compare the local knowledge and uses of these five popular anti-infectious plants.

Methods: A survey was carried out among 43 traditional healers from different regions of Burundi to fully repertory the uses of these five medicinal plants and define consensus in their uses through their fidelity levels and use values for each cited disease. Phytochemical analyses of these plants allowed to identify their main classes of secondary metabolites.

Results: For the five investigated plants, the leaves and aerial parts are the organs mainly used. Preparation methods include maceration, decoction and squeezing of juice, powdering and calcination. From their fidelity levels and use values, the studied plants appear extensively reported for infectious diseases, except for U. massaica, that is mainly used in inflammatory conditions. The phytochemical classes we detected in these plants [terpenoids, (poly)phenolic compounds including flavonoids and tannins, saponins] may explain their uses and warrant further studies.

Conclusions: The survey indicates that the five plants studied are widely used in the treatment of infectious diseases. The convergence of some usages indicates a plausibility of efficacy and safety, coherent with the EU concept of "Traditional Herbal Medicine", which points to possible rational recommendations of treatments. A study of the antimicrobial activities of these plants would complete this work.

Keywords: Medicinal plants, traditional medicine, infectious diseases, phytochemistry, Burundi.