Table 2 Antibiotic resistances of Listeria monocytogenes isolates from raw fresh vegetable samples
Antimicrobial class | Antimicrobial agent (disk content, μg or U) | Critical value (mm) | Sample number(%) | ||||
|---|---|---|---|---|---|---|---|
S | I | R | S | I | R | ||
Aminoglycosides | Kanamycin(30) | ≥18 | 14–17 | ≤13 | 26 (86.7) | 2 (6.7) | 2 (6.7) |
Gentamicin(10) | ≥15 | 13–14 | ≤12 | 28 (93.3) | 0 | 2 (6.7) | |
Streptomycin(10) | ≥15 | 12–14 | ≤11 | 19 (63.3) | 9 (30) | 2 (6.7) | |
Fluoroquinolones | Levofloxacin(5) | ≥19 | 16–18 | ≤15 | 28 (93.3) | 2 (6.7) | 0 |
Ciprofloxacin(5) | ≥21 | 16–20 | ≤15 | 22 (73.3) | 7 (23.3) | 1 (3.3) | |
Folate pathway inhibitors | Sulfamethoxazole /trimethoprim (23.75/1.25) | ≥16 | 11–15 | ≤10 | 30 (100) | 0 | 0 |
β-lactam group | Sulbactam/ampicilin(10/10) | ≥15 | 12–14 | ≤11 | 29 (96.7) | 1 (3.3) | 0 |
Macrolides | Erythromycin(15) | ≥23 | 14–22 | ≤13 | 27 (90) | 2 (6.7) | 1 (3.3) |
Ansamycins | Rifampin(5) | ≥20 | 17–19 | ≤16 | 22 (73.3) | 6 (20) | 2 (6.7) |
Lincosamides | Clindamycin(2) | ≥21 | 15–20 | ≤14 | 4 (13.3) | 7 (23.3) | 19 (63.3) |
Tetracyclines | Tetracycline(30) | ≥19 | 15–18 | ≤14 | 29 (96.7) | 0 | 1 (3.3) |
Doxycycline(30) | ≥16 | 13–15 | ≤12 | 29 (96.7) | 0 | 1 (3.3) | |
Glycopeptides | Vancomycina(30) | ≥17 | 15–16 | ≤14 | 25 (83.3) | 3 (10) | 2 (6.7) |
Phenicols | Chloramphenicol (30) | ≥18 | 13–17 | ≤12 | 28 (93.3) | 2 (6.7) | 0 |
β-Lactam | Ampicillin | <2 μg/mL | – | ≥2 μg/mL | 30 (100.0) | 0 (0) | 0 (0) |
β-Lactam | Penicillin | <2 μg/mL | – | ≥2 μg/mL | 30 (100.0) | 0 (0) | 0 (0) |