Table 3.
Antibacterial activity of 6a-f compounds and ciprofloxacin against tested bacterial strains.
| Compounds μg/disc |
Zone of inhibition [mm±SD] |
||||
|---|---|---|---|---|---|
| BS | BC | SA | EC | PA | |
| 6d | |||||
| 100 | – | 9.6 ± 1.2 | 10.3 ± 0.6 | 8.3 ± 1.5 | 11.7 ± 0.6 |
| 300 | – | 11.0 ± 0.0 | 12.3 ± 0.6 | 10.3 ± 0.7 | 13.0 ± 0.3 |
| 500 | – | 13.3 ± 0.6 | 14.6 ± 1.2 | 12.6 ± 0.7 | 13.3 ± 0.6 |
| MIC (μg/ml) | >500 | >500 | 500s | >500 | 500s |
| 6b | |||||
| 100 | – | – | – | 10.6 ± 1.2 | 12.3 ± 0.7 |
| 300 | – | – | – | 13.3 ± 1.5 | 13.6 ± 0.6 |
| 500 | – | – | – | 14.7 ± 0.6 | 15.3 ± 0.3 |
| MIC (μg/ml) | >500 | >500 | >500 | 500s | 500s |
| 6a | |||||
| 100 | 11.3 ± 1.2 | 12.7 ± 0.6 | – | – | – |
| 300 | 13.1 ± 0.6 | 14.6 ± 0.3 | – | – | – |
| 500 | 14.6 ± 0.7 | 15.3 ± 0.3 | – | – | – |
| MIC (μg/ml) | 500s | 500s | >500 | >500 | >500 |
| 6e | |||||
| 100 | 9.6 ± 0.6 | 10.3 ± 0.6 | – | – | – |
| 300 | 13.1 ± 0.3 | 11.3 ± 0.6 | – | – | – |
| 500 | 14.3 ± 0.6 | 13.3 ± 0.6 | – | – | – |
| MIC (μg/ml) | >500 | >500 | >500 | >500 | >500 |
| 6f | |||||
| 100 | – | – | – | – | – |
| 300 | – | – | – | – | – |
| 500 | – | – | – | – | – |
| MIC (μg/ml) | >500 | >500 | >500 | >500 | >500 |
| 6c | |||||
| 100 | – | 12.7 ± 0.6 | 10.6 ± 1.2 | 11.3 ± 0.7 | 12.3 ± 0.6 |
| 300 | – | 13.7 ± 1.1 | 12.3 ± 0.6 | 13.6 ± 1.2 | 14.6 ± 0.6 |
| 500 | – | 15.3 ± 0.7 | 13.3 ± 0.3 | 14.6 ± 0.3 | 16.3 ± 0.6 |
| MIC (μg/ml) | >500 | 500s | >500 | >500 | 500s |
| Ciprofloxacin | |||||
| 10 | 13.33 ± 1.15 | 13.67 ± 0.58 | 9.67 ± 0.58 | 12.33 ± 1.15 | 13.33 ± 0.58 |
| 50 | 15.0 ± 0.0 | 16.0 ± 0.0 | 11.67 ± 0.58 | 16.0 ± 0.0 | 20.0 ± 1.0 |
| 100 | 18.0 ± 0.0 | 19.33 ± 0.58 | 17.33 ± 0.58 | 18.33 ± 0.58 | 23.0 ± 0.0 |
| MIC (μg/ml) | 31.25c | 31.25c | 15.6c | 15.6 | 7.8c |
BS: B. subtilis BC: B. cereus SA: S. aureus EC: E. coli PA: P. aeruginosa.
NA: not active s: bacteriostatic c: bactericidal.