Table 5.
Antimicrobial activity of essential oils against Brochothrix thermosphacta ATCC 11509 and Pseudomonas fluorescens ATCC 13525 using paper disk diffusion method
| B. thermosphacta ATCC 11509 | P. fluorescens ATCC 13525 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 11 | 1/21 | 1/101 | 1/201 | 1/401 | 1 | 1/2 | 1/10 | 1/20 | 1/40 | |
| Essential oils | Diameter of inhibition zone (mm)2 | |||||||||
| Cinnamomum cassia | 24.9 ± 0.4a | 22.7 ± 0.3a | 19.3 ± 0.2a | 13.3 ± 0.3a | 7.3 ± 0.5a | 23.1 ± 0.6a | 21.1 ± 1.6a | 16.1 ± 0.4a | 11.2 ± 0.7a | 8.5 ± 0.3ac |
| Cymbopogon flexuosus | 18.9 ± 0.3b | 15.8 ± 0.1b | 9.7 ± 0.4b | 8.7 ± 0.2b | 7.7 ± 0.1a | 9.4 ± 0.0b | 7.5 ± 0.1b | 7.2 ± 0.0b | – | – |
| Cymbopogon nardus | 15.4 ± 0.3c | – | – | – | – | – | – | – | – | – |
| Coriandrum sativum | 16.3 ± 0.3d | 13.5 ± 0.5c | – | – | – | 12.8 ± 0.6c | 10.5 ± 0.9c | 7.3 ± 0.2b | – | – |
| Cinnamomum verum | 24.2 ± 0.7e | 23.1 ± 0.1a | 17.2 ± 0.4c | 12.0 ± 0.3c | – | 23.6 ± 0.3d | 21.4 ± 0.3a | 12.5 ± 0.4c | 10.4 ± 0.1b | 8.5 ± 0.2ac |
| Eugenia caryophyllus | 15.6 ± 0.2c | 14.7 ± 0.1d | 12.5 ± 0.2d | 7.8 ± 0.1d | – | 9.9 ± 0.3e | 9.3 ± 0.2d | 8.5 ± 0.1d | 7.0 ± 0.1c | – |
| Kaempferia galanga | – | – | – | – | – | – | – | – | – | – |
| Origanum compactum | 27.3 ± 0.5f | 25.3 ± 0.4e | 20.8 ± 0.7e | 14.2 ± 0.9e | 8.4 ± 0.2b | 9.5 ± 0.4b | 9.2 ± 0.0d | 8.3 ± 0.2df | 7.4 ± 0.2d | 7.1 ± 0.2b |
| Origanum heracleoticum | 30.3 ± 0.8 g | 29.0 ± 0.4f | 25.8 ± 0.2f | 22.3 ± 0.8f | 11.7 ± 0.9c | 12.3 ± 0.5f | 11.8 ± 0.3e | 10.5 ± 0.2e | 9.4 ± 0.1e | 8.7 ± 0.1a |
| Origanum majorana | 16.7 ± 0.2d | 12.0 ± 0.2g | – | – | – | 15.9 ± 0.6g | 12.9 ± 0.2f | 8.1 ± 0.4f | 7.7 ± 0.2d | – |
| Salvia officinalis | 14.0 ± 0.2h | 12.0 ± 0.4g | 7.2 ± 0.1g | – | – | – | – | – | – | – |
| Salvia sclarea | 10.5 ± 0.2i | 9.4 ± 0.2h | – | – | – | – | – | – | – | – |
| Thymus capitatus | 23.5 ± 0.6j | 21.5 ± 0.5i | 18.7 ± 0.4h | 16.4 ± 0.2g | 12.8 ± 0.1d | 11.7 ± 0.3h | 11.0 ± 0.1g | 9.5 ± 0.1g | 9.2 ± 0.2e | 8.3 ± 0.1c |
| Thymus mastichina | 11.9 ± 0.4k | 10.4 ± 0.3j | 7.1 ± 0.1g | – | – | – | – | – | – | – |
| Thymus vulgaris thymoliferum | 29.6 ± 0.8 l | 27.3 ± 0.5k | 24.7 ± 0.4i | 18.2 ± 1.2h | 8.9 ± 0.2b | 11.0 ± 0.3i | 10.2 ± 0.2c | 8.4 ± 0.0df | 7.6 ± 0.2d | 7.1 ± 0.3b |
| Ampicillin3 | 31.0 ± 1.1 | ND | ND | ND | ND | – | ND | ND | ND | ND |
| Chloramphenicol3 | 29.8 ± 0.4 | ND | ND | ND | ND | – | ND | ND | ND | ND |
| Streptomycin3 | – | ND | ND | ND | ND | 12.4 ± 0.4 | ND | ND | ND | ND |
| Blank control (ethanol) | – | – | – | – | – | – | – | – | – | – |
(–)Diameter of inhibitory zone <7 mm considered as no antimicrobial activity. ND, not determined.
1
Concentrations (1, 1/2, 1/10, 1/20, 1/40) used were v/v.
2
Values are mean diameter of inhibitory zone (mm) ±SD of five replicates, followed by different letters in column are significantly different (P < 0.05). The diameter of paper disk (6 mm) is included.
3
Ampicillin (10 μg), chloramphenicol (30 μg), and streptomycin (10 μg) used as positive control.