Strains | Antibiotic | MICA | [A] | FICA | MICB | [B] | FICB | FICI a | Interpretation |
|---|
MDRPA | CHL | 256 | 64 | 0.25 | 16 | 0.25 | 0.0156 | 0.2656 | synergy |
OXA | 1024 | 256 | 0.25 | 16 | 0.25 | 0.0156 | 0.2656 | synergy |
CIP | 1024 | 64 | 0.0625 | 16 | 0.25 | 0.0156 | 0.0781 | synergy |
MDREC | CHL | 1024 | 512 | 0.5 | 64 | 16 | 0.25 | 0.75 | additive |
OXA | 1024 | 16 | 0.0156 | 64 | 16 | 0.25 | 0.2656 | synergy |
CIP | 1 | 0.0009 | 0.0009 | 64 | 1 | 0.0156 | 0.0165 | synergy |
- MDRPA: Multidrug-resistant Pseudomonas aeruginosa (CCARM 2109)
- MDREC : Multidrug-resistant Escherichia coli (CCARM 1229)
- CHL: chloramphenicol, OXA: oxacillin, CIP: ciprofloxacin
- MICA : MIC (μg/ml) of antibiotic alone, [A]: MIC (μg/ml) of antibiotic in combination,
- MICB : MIC (μg/ml) of SAMP-5 alone, [B]: MIC (μg/ml) of SAMP-5 in combination.
- FICA : fractional inhibitory concentration of antibiotic
- FICB : fractional inhibitory concentration of SAMP-5
- FICI : fractional inhibitory concentration index, a FICI = [A] / MICA + [B] / MICB
- FICI of ≤ 0.5 was interpreted as synergy, 0.5 < FICI ≤ 1.0 as additive, 1.0 < FICI ≤ 4.0 as indifferent, and an FICI > 4.0 as antagonism
