Anti-tubercular activity of essential oils from Cymbopogon citratus, C. nervatus and C. proximus

Abstract

Tuberculosis (TB) remains a major global health problem, especially with the emergence of drug resistance. It ranks as the second leading cause of death from an infectious disease worldwide, after the human immunodeficiency virus (HIV). This research was conducted to evaluate in vitro anti-tubercular activity of the essential oils from three aromatic herbs belong to the Genus Cymbopogon (Family Poaceae), Cymbopogon citratus (leaves), C. nervatus (inflorescences) and C. proximus (leaves and inflorescences). The essential oils were tested in vitro for their activity against nine clinical isolates and arnreference susceptible strain (H37Rv) M. tuberculosis, using Lowenstein-Jensen (LJ) medium containing glycerol, at concentrations of 75-15 I¼l/mL. Evaluation of antitubercular activity was determined using the absolute concentration method which is expressed in terms of the minimal inhibitory concentration (MIC). The investigated essential oils from the genus Cymbopogonexhibited anti-tubercular activity, in Lowenstein-Jensen medium, towards all the tested strains of M. tuberculosis isolates, up to concentration of 15 µl/ml for each oil. Some strains showed resistance towards Rifampicin, a marker drug for MDR-TB. This research findings represents additional challenges for essential oils as promising natural products leads for tuberculosis (specially MDR) drug discovery and development.