Anti-tuberculosis activity of bio-active compounds from Lantana camara L., Euphorbia hirta L., Mukia maderaspatana (L.) M. Roem, and Abutilon indicum (L.)

Introduction: Tuberculosis (TB) is a major cause of morbidity and mortality and deserves global attention to identify new effective drugs. The present in-vitro study is an attempt to explore the anti-TB potential of selected, commonly available, and well-known medicinal plants, namely, Lantana camara L., Euphorbia hirta L., Mukia maderaspatana (L.) M. Roem, and Abutilon indicum (L.) Sweet known to have proven antimicrobial activity. Methods: The cold extraction procedure was adopted for preparing the methanolic crude extracts from the four selected medicinal plants.The anti-tuberculosis activity of methanolic crude extracts of the plants was tested against multi-drug resistant (MDR) clinical isolates of Mycobacterium tuberculosis ( Mtb ) and Mtb H37Rv using luciferase reporter phage (LRP) assay. The minimum inhibitory concentration (MIC) of the selected potent compounds was estimated using the broth dilution method. Results: The phytochemical and gas chromatography-mass spectrometry (GC-MS) analyses showed that phy-tocompounds that have been reported earlier exhibit anti-TB activity are abundant. The LRP assay revealed the heightened inhibitory activity of methanolic crude extracts and individual fractions against the tested clinical and laboratory Mtb strains. MICs of the selected plant fractions against Mtb strains were found to be in a range of 400-1600 mu g/mL in which Mukia maderaspatana (L.) M. Roem showed the lowest MIC of 400 mu g/mL and this was validated by two different methods. Conclusion: The four medicinal plants examined as potential sources for anti-TB drug formulations initially look promising. Further investigation combining these plants should be considered as they may provide the basis for developing future treatment for TB.