Abstract
Treatment of tuberculosis has become a challenge due to the rapid increase of multidrug and extensive drug resistant Mycobacterium tuberculosis. Medicinal plants might represent a possible source for new potent antibacterials to which pathogen strains are not resistant. In this study, five Combretum plant species-Combretum imberbe, Combretum zeyheri, Combretum hereroense, Combretum elaeagnoides and Combretum platypetalum used in traditional medicine were exposed to susceptibility tests to determine the effects of drug accumulation in avirulent M. smegmatis and M. aurum. The MIC values of the potent plant species was then determined. Using the agar disc diffusion assay, it was found out that the only the ethanolic extract from Combretum imberbe was active on M. smegmatis and it had an MIC of 125 μg/ml in the broth microdilution assay. However, using Sabouraud dextrose broth, Combretum platypetalum was found to have antimycobacterial effects which were not detected when using the agar disc diffusion assay. MIC of 63 and 125 μg/ml and MBCs of 250 and 500 μg/ml were obtained for C. platypetalum for M. smegmatis and M. aurum respectively. C. imberbe extract gave an MIC of 125 μg/ml but did not produce MBCs suggesting that it is bacteriostatic and not bactericidal. Drug accumulation transport assays were performed on C. imberbe, C. hereroense and C. platypetalum and results show that extracts from two plants are efflux pump inhibitors. Determination of the IC50 for the transport process was as conducted on Combretum imberbe using CCCP as the standard inhibitor. Both plants extract in addition to C. hereroense maybe potential sources for leads for efflux pump inhibitor in mycobacteria.
Highlights
Tuberculosis (TB) has threatened humanity for thousands of years and remains one of the deadliest diseases on planet earth [1]
The current study showed that two plant extracts from Combretum imberbe and Combretum platypetalum had antimycobacterial activity against the two species of mycobacteria, with C. imberbe having an effect only on M. smegmatis
Combretum imberbe ethanolic extracts was found to be bacteristatic to Mycobacterium smegmatis and both Combretum imberbe and Combretum hereroense are potential efflux pump inhibitors in Mycobacterium smegmatis
Summary
Tuberculosis (TB) has threatened humanity for thousands of years and remains one of the deadliest diseases on planet earth [1]. It is the leading cause of death worldwide from a single pathogen, claiming more lives than AIDS, malaria, diarrhea, leprosy, and all other tropical diseases combined [2]. The increase in TB incidence in Africa is strongly associated with the prevalence of HIV infection among TB patients, exceeding 60% in South Africa, Botswana, Zambia, and Zimbabwe [4]. It has indicated that Zimbabwe had 71,961 tuberculosis cases in 2007 and an estimated incidence rate of 540 cases per 100,000 populations [5]. The mycobacterium is aerobic, pathogenic and usually establishes its infection in the lungs [2]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
