Table 1.
Interactions between 1,3,4-thiadiazoles (C1, NTBD, Et-NTBD, and C1-NTBD) and amphotericin B (AmB) in terms of activity against reference strains in vitro after 48-h incubation: MIC—minimal inhibiting concentration of the compound, ∑FIC—coefficient, which is the sum of partial concentrations inhibiting the growth of the pathogens. The interactions were determined based on the specified ranges: synergy (∑FIC ≤ 0.5), indifferent (∑FIC ≥ 0.5 to 4), antagonism (∑FIC > 4); ** = synergy.
|
Strain |
1,3,4-thiadiazole | Separate Treatment | Combinatory Treatment 1,3,4-thiadiazole +AmB | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2 (µg/mL) of 1,3,4-thiadiazole |
4 (µg/mL) of 1,3,4-thiadiazole |
8 (µg/mL) of 1,3,4-thiadiazole |
16 (µg/mL) of 1,3,4-thiadiazole |
32 (µg/mL) of 1,3,4-thiadiazole |
64 (µg/mL) of 1,3,4-thiadiazole |
||||||||||
| MIC 1,3,4-thiadiazole (µg/mL) |
MIC AmB (µg/mL) | MIC AmB (µg/mL) | ƩFIC | MIC AmB (µg/mL) | ƩFIC | MIC AmB (µg/mL) | ƩFIC | MIC AmB (µg/mL) | ƩFIC | MIC AmB (µg/mL) | ƩFIC | MIC AmB (µg/mL) | ƩFIC | ||
|
C. albicans
NCPF 3153 |
C1 | 128 | 0.5 | 0.25 | 0.52 |
0.125 | 0.29 ** | 0.125 | 0.33 ** | 0.0625 | 0.29 ** | 0.0312 | 0.40 ** | 0.0312 | 0.73 |
| NTBD | >128 | 0.5 | 0.25 | 0.51 | 0.25 | 0.52 | 0.25 | 0.53 | 0.125 | 0.31 ** | 0.25 | 0.62 ** | 0.25 | 0.75 | |
| Et-NTBD | >128 | 0.5 | 0.5 | 1.01 | 0.5 | 1.02 | 0.5 | 1.03 | 0.5 | 1.06 | 0.5 | 1.13 | 0.25 | 0.625 | |
| C1-NTBD | 128 | 0.5 | 0.5 | 1.01 | 0.5 | 1.03 | 0.5 | 1.06 | 0.5 | 1.13 | 0.5 | 1.25 | 0.25 | 1 | |
|
C. parapsilosis
ATCC 22019 |
C1 | 64 | 1 | 0.5 | 0.53 | 0.25 | 0.31 ** | 0.125 | 0.25 ** | 0.0625 | 0.31 ** | 0.0312 | 0.53 | - | - |
| NTBD | >128 | 1 | 0.5 | 0.51 | 0.25 | 0.26 ** | 0.25 | 0.28 ** | 0.25 | 0.31 ** | 0.25 | 0.38 ** | 0.25 | 0.5 ** | |
| Et-NTBD | 16 | 1 | 1 | 1.125 | 0.5 | 0.75 | 0.5 | 1 | - | - | - | - | - | - | |
| C1-NTBD | 64 | 1 | 1 | 1.03 | 1 | 1.06 | 1 | 1.13 | 1 | 1.25 | 0.5 | 1 | - | - | |