Table 2.
Antibacterial activity of ent-copalic acid against multiresistant Gram-positive and Gram-negative bacteria
| Minimum Inhibitory Concentration - µg mL−1 | ||
|---|---|---|
| Multiresistant Microorganisms | Copalic acid (OC-2) | Positive Control |
| S. epidermidis (ATCC 14490) | 50.0 | 1.5 |
| S. epidermidis (clinical isolate) | 15.6 | 1.5 |
| S. capitis (ATCC 27840) | 50.0 | 0.7 |
| S. capitis (clinical isolate) | 31.25 | 0.7 |
| S. aureus (WB81-USA 400) | 25.0 | 0.7 |
| S. aureus (W7749-USA 200) | 25.0 | 0.7 |
| S. aureus (ATCC 29213) | 25.0 | 0.7 |
| S. aureus (surgical wound) | 15.6 | 1.5 |
| S. aureus (catheter) | a | 1.5 |
| E. faecalis (ATCC 19433) | 25.0 | 1.5 |
| E. faecalis (clinical isolate) | 15.6 | 5.9 |
| E. faecium (ATCC 19434) | 50.0 | 1.5 |
| E. faecium (hospital outbreak) | 50.0 | 5.9 |
| S. haemolyticus (ATCC 29970) | 100.0 | 1.5 |
| S. haemolyticus (clinical isolate) | 15.6 | 1.5 |
| S. pneumoniae (clinical isolate) | 31.25 | 2.9 |
| P. aeruginosa (clinical isolate) | a | 5.9 |
| A. calcoaceticus (clinical isolate) | a | 0.4 |
| E. coli (clinical isolate) | a | 5.9 |
| K. pneumoniae (clinical isolate) | a | 2.9 |
aInactive in the evaluated concentration (MIC values higher than 200 µg mL-1); Positive Control (PC), vancomycin and gentamicin; Negative Control (5 % DMSO solution v/v) did not affect growth of the microorganisms