Evaluation of the antibacterial activity of three types of Vernonia amygdalina Del. leaf extract sold in the markets of Lomé-Togo

Abstract

Nowadays, the emergence of multi-resistant bacteria and the absence of new antibiotics are an increasing risk of therapeutic impasse. Nutraceuticals are plants which are reputed to have therapeutic properties and which are consumed as food. One of these plants consumed as a leafy vegetable, having amoebicidal properties and very popular among togolese populations is Vernonia amygdalina. The objective of this work was to evaluate the antibacterial activity of three types of V. amygdalina leaf extracts. The extracts were obtained by maceration of dried leaf powder (hydroethanolic 30:70), by decoction of fresh leaves and crushed boiled leaves (FEBEVA). The evaluation of the antibacterial activity of the extracts was carried out by the diffusion method and microdilution. The decoctate had a bactericidal effect on S. aureus and K. pneumoniae. FEBEVA was only activated on day 7 and only with a concentration of 400 mg. Phytochemical screening revealed secondary metabolites such as saponosides, tannins, triterpenes, polyphenols, sterols, alkaloids. This work has provided a scientific basis for the use of Vernonia amygdalina in traditional pharmacopoeia, particularly in the treatment of bacterial pathologies.