The antituberculous activities of TUM and TUM-N were evaluated in comparison with other aminoglucoside antibiotics in vitro by using the silicone-coated slide culture method (SSC).
The results obtained are as follows: (1) The minimum inhibitory concentrations (MIC) of TUM and TUM-N are between 1.9 to 3.9μg/ml to H37Rv-S strain. However, the MIC of these drugs to the strains resistant to Viomycin (VM) and Capreomycin (CPM) are lowered to 62.5μg/ml and 31.3μg/ml, respectively. (2) The minimum bactericidal concentrations (MBC) of TUM and TUM-N are 3.9-7.8μg/ml to H37Rv-S strain, but remarkably lowered to the strains resistant to VM and CPM. These results indicate the existence of incomplete cross-resistance among these aminoglucoside antibiotics.
