Table 4.
Desctruction effect of different EOs alone and in combination with norfloxacin on mature biofilm.
| EO mg/mL | Norfloxacin µg/mL | Synergism | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Strains | Essential Oil | sMIC50 a | % Destr. ± SD b | sMIC50 c | % Destr. ± SD d | AB ug/mL e | EO mg/mL f | AB ± EO% Destr. ± SD g | FICI |
| E. faecalis ATCC 29212 | Cinnammonum zeylanicum | 50.4 | 52.5 ± 0.70 | 256 | 49.2 ± 0.90 | 8.0 | 2.5 | 53.2 ± 1.00 | 0.08 |
| S. aureus Ig22 | Cinnammonum zeylanicum | 6.3 | 52.1 ± 0.70 | 512 | 37.0 ± 0.39 | 16.0 | 0.3 | 60.2 ± 0.77 | 0.08 |
| S. epidermidis IG4 | Cinnammonum zeylanicum | 12.6 | 60.0 ± 1.00 | 64 | 56.0 ± 0.50 | 2.0 | 0.6 | 64.5 ± 0.04 | 0.08 |
| S. aureus ATCC 29213 | Cinnammonum zeylanicum | 12.6 | 48.0 ± 1.00 | 256 | 52.2 ± 1.00 | 8.0 | 0.6 | 66.9 ± 0.90 | 0.08 |
| E. faecalis ATCC 29212 | Mentha piperita | 11.4 | 50.0 ± 1.00 | 256 | 49.2 ± 0.80 | 16.0 | 0.6 | 53.5 ± 0.90 | 0.11 |
| S. aureus Ig22 | Mentha piperita | 11.4 | 51.1 ± 0.60 | 512 | 37.0 ± 0.10 | 16.0 | 2.3 | 47.7 ± 0.12 | 0.23 |
| S. epidermidis IG4 | Mentha piperita | 45.5 | 44.8 ± 0.70 | 64 | 56.0 ± 0.59 | 2.0 | 2.3 | 58.9 ± 0.90 | 0.08 |
| S. aureus ATCC 29213 | Mentha piperita | 22.7 | 45.1 ± 1.00 | 256 | 52.2 ± 0.70 | 8.0 | 1.1 | 50.1 ± 1.00 | 0.08 |
| E. faecalis ATCC 29212 | Origanum vulgare | 5.5 | 49.2 ± 0.60 | 256 | 49.2 ± 0.70 | 8.0 | 0.3 | 53.2 ± 0.20 | 0.08 |
| S. aureus Ig22 | Origanum vulgare | 11.0 | 57.3 ± 1.00 | 512 | 37.0 ± 0.88 | 32.0 | 0.6 | 47.7 ± 0.55 | 0.11 |
| S. epidermidis IG4 | Origanum vulgare | 5.7 | 61.9 ± 0.60 | 64 | 56.0 ± 1.00 | 2.0 | 0.3 | 59.4 ± 0.90 | 0.08 |
| S. aureus ATCC 29213 | Origanum vulgare | 5.7 | 56.8 ± 1.00 | 256 | 52.2 ± 0.05 | 32.0 | 0.3 | 55.6 ± 0.32 | 0.18 |
| E. faecalis ATCC 29212 | Thymus vulgaris | 21.7 | 47.8 ± 0.80 | 256 | 49.2 ± 0.77 | 8.0 | 1.1 | 65.7 ± 0.80 | 0.08 |
| S. aureus Ig22 | Thymus vulgaris | 43.5 | 50.5 ± 0.50 | 512 | 37.0 ± 0.90 | 16.0 | 2.2 | 63.9 ± 0.80 | 0.08 |
| S. epidermidis IG4 | Thymus vulgaris | 10.9 | 54.1 ± 0.30 | 64 | 56.0 ± 0.33 | 4.0 | 0.5 | 52.4 ± 1.00 | 0.11 |
| S. aureus ATCC 29213 | Thymus vulgaris | 10.9 | 59.4 ± 0.40 | 256 | 52.2 ± 0.80 | 8.0 | 0.5 | 58.4 ± 0.90 | 0.08 |
a: sMIC50: sessile minimal inhibitory concentration 50; b: % biofilm destruction ± standard deviation; c: concentration of the antibiotic in the combination; d: Concentration of the EO in the combination; e: concentration of antibiotic in the mixture; f: concentration of essential oil in the mixture; g: biofilm combination mixture inhibition rate; FICI: fractional inhibitory concentration; AB: antibiotic; EO: essential oil.