Table 3.
FICI for the synergistic effect of PapMA-3 in combination with antibiotics against CRABs.
| PapMA-3 with Antibiotics |
MIC (μg·mL−1) | MIC in Combination (μg·mL−1) | ||||
|---|---|---|---|---|---|---|
| Strain | PapMA-3 | Antibiotics | PapMA-3 | Antibiotics | FICI # | |
| PapMA-3 + Imipenem | CRAB C1 | 16 | 64 | 4.0 | 4.0 | 0.31 * |
| CRAB C2 | 16 | 64 | 4.0 | 8.0 | 0.38 | |
| CRAB C3 | 16 | 64 | 8.0 | 1.0 | 0.52 | |
| CRAB C4 | 32 | 64 | 8.0 | 8.0 | 0.38 | |
| CRAB C5 | 16 | 64 | 8.0 | 16 | 0.75 | |
| PapMA-3 + Meropenem | CRAB C1 | 16 | 128 | 4.0 | 32 | 0.50 |
| CRAB C2 | 16 | 64 | 8.0 | 32 | 1.00 | |
| CRAB C3 | 16 | 64 | 8.0 | 16 | 0.75 | |
| CRAB C4 | 32 | 128 | 8.0 | 32 | 0.50 | |
| CRAB C5 | 16 | 64 | 8.0 | 16 | 0.75 | |
| PapMA-3 + Rifampin | CRAB C1 | 16 | 128 | 4.0 | 8.0 | 0.31 |
| CRAB C2 | 16 | 64 | 2.0 | 8.0 | 0.25 | |
| CRAB C3 | 16 | 128 | 4.0 | 16 | 0.38 | |
| CRAB C4 | 32 | 128 | 2.0(8.0) | 8.0(4.0) | 0.13(0.27) | |
| CRAB C5 | 16 | 256 | 4.0 | 64 | 0.50 | |
| PapMA-3 + Erythromycin | CRAB C1 | 16 | >512 | 4.0 | 128 | 0.38 |
| CRAB C2 | 16 | 512 | 8.0 | 128 | 0.75 | |
| CRAB C3 | 16 | 512 | 8.0 | 64 | 0.63 | |
| CRAB C4 | 32 | >512 | 4.0(8.0) | 64(16) | 0.19(0.27) | |
| CRAB C5 | 16 | >512 | 4.0 | 256 | 0.50 | |
| PapMA-3 + Vancomycin | CRAB C1 | 16 | 256 | 2.0(4.0) | 32(16) | 0.25(0.31) |
| CRAB C2 | 16 | 256 | 2.0 | 32 | 0.25 | |
| CRAB C3 | 16 | 256 | 8.0 | 4.0 | 0.52 | |
| CRAB C4 | 32 | 512 | 4.0(8.0) | 64(16) | 0.25(0.28) | |
| CRAB C5 | 16 | 256 | 4.0 | 64 | 0.50 | |
| PapMA-3 + Linezolid | CRAB C1 | 16 | 256 | 4.0 | 64 | 0.50 |
| CRAB C2 | 16 | 256 | 4.0 | 64 | 0.50 | |
| CRAB C3 | 16 | 256 | 8.0 | 128 | 1.00 | |
| CRAB C4 | 32 | 512 | 8.0 | 64 | 0.38 | |
| CRAB C5 | 16 | 512 | 4.0 | 128 | 0.50 | |
# The fractional inhibitory concentration index (FICI) was calculated according to Equation (1). If the MIC value was not obtained at the highest concentration measured due to poor antibacterial activity, the FICI was considered to be twice the value of the measurement limit. * Combinations that showed synergistic effects are shaded in gray. Where there were multiple sets of combinations with low FICI values, they are listed in parentheses.