Antimycobacterial activities of selected plants used in the management of tuberculosis in Sekhukhune (Limpopo Province), South Africa

Abstract

Tuberculosis (TB) continues to be a devastating disease of the world affecting more than two million people annually with one-third of the world’s populations suffering from the menace. The management of TB was in the use of orthodox medicines which are not only expensive but presents severe side effects. Thus, efforts are recently geared towards the use of alternative therapy from natural sources which could offer a lasting solution to the treatment of the diseases with little or no side effects. The study investigated the antimicrobial potentials of four medicinal plants used by Bapedi tribe of Sekhukhune area, Limpopo Province of South Africa. The antimycobaceterial efficacy of Aloe marlothii, Maerua angolensis, Drimia elata and Elephantina elephantorrhiza which were selected based on ethnobotanical study carried-out in the study was tested in four solvents such as ethanol, methanol, hydroethanol and dichlrormethane against four mycobacterium species such as M. tuberculosis, M. smegmatis, M. peregrinum, M. haemophilus and other gram positive and gram negative bacteria isolates using agar well dilution method and streak plate disc diffusion assay as a way of validating the anti-tuberculosis potentials of the plants. The results revealed the anti TB activity of the four plants particularly M. angolensis, D. elata and E. elephantorrhiza which were reported for the first time in this study. Similarly, the results revealed varied degrees of antimycobacterial activities of most of the screened extracts (particularly ethanolic and methanol) going by the zone of inhibition values (10 – 32 mm) as well as minimum inhibitory concentration (MIC) values that fell within the range of 0.098 - 1.56 μg/mL and as such, could be adjudged to possess anti TB potentials. Conclusively, the anti TB activity witnessed by the four plants could be attributed to the presence of the secondary metabolites which are responsible for the elicited effect. The study also validates the use of these plants in the management of tuberculosis by the Sekhukhune people of Limpopo Province, South Africa.