Anti-tuberculosis activity of selected medicinal plants against Mycobacterium tuberculosis

Introduction: Tuberculosis (TB) remains a serious health problem in many regions of the world. The increased rate of multi-drug resistant and extensively-drug resistant strains of the organism further complicates the problem of TB control and requires developing new anti-TB drugs which can shorten the treatment period, with fewer adverse effects. Abundant research is available for the biotherapeutic potential of naturally occurring compounds in various diseases but has been lagging in the area of TB. Objectives: The current study was designed to investigate the antimycobacterial activity of three selected medicinal plants, vis Catharanthus roseus, Casia fistula, and Withania somnifera. Methods: Extraction was performed using the Soxhlet extraction method deployed at 45 o C, and the solvent was evaporated by Rota vacuum evaporator at Deshbandhu College, University of Delhi. The ethanol extracts of all three plants were assayed for their Mycobacterium tuberculosis inhibitory activity using the BACTEC MGIT960 susceptibility test method at the National Institute of TB and Respiratory Diseases (NITRD), New Delhi. The control and the test tubes were inoculated with the H37 Rv strain with a concentration of 12.5mg/ml in the test tubes. Results: The control tube showed growth after 7-10 days of incubation whereas the tubes with extract did not show any sign of growth even at prolonged incubation till 30-42 days. Conclusion: Our study exhibited that extracts of all three plants showed inhibitory activity against the Mycobacterium tuberculosis H37Rv strain. Further studies are required to investigate the mechanism of action, potential for bacterial clearance, and immunomodulatory effects. Exploring the potential of phytodrugs and other plant-based products that can reduce the side effects of standard drugs in synergistic combinations may improve the overall outcome for patients and develop sustainable, environmentally friendly treatments