Antibacterial activity of M. koenigii and A. nilagirica ethanol leaf extracts against M. smegmatis and M. bovis BCG. 4-5 × 105 M. smegmatis (A,C) and M. bovis BCG (B, D) were incubated with different concentrations of M. koenigii and A. nilagirica ethanol leaf extracts for 24 h in 7H9 medium and the number of colony forming units were counted after 72 h and 3 weeks for M. smegmatis and M.bovis BCG, respectively by plating serially diluted samples on 7H9 medium. Media containing bacteria alone was used as control. Experiments were performed in triplicates, means ± the standard deviation (SD) are shown. **,P ≤ 0.0005; *,P ≤ 0.01.