Table 6.
Antimicrobial activity of hemp essential oil and extracts.
| Extract | HEO | HSE | HTE | HWE | Antibiotics |
|---|---|---|---|---|---|
| Microorganism | MIC [mg/L] | ||||
| Gram-positive bacteria | |||||
| Staphylococcus aureus | 62.5 a | 0.98 b | 0.98 b | 31.3 c | 0.98 # |
| Staphylococcus aureus * | 1000 a | 3.9 b | 3.9 b | 125 c | 0.98 # |
| Staphylococcus epidermidis | 1000 a | 3.9 b | 3.9 b | 125 c | 0.12 # |
| Micrococcus luteus | 15.6 a | 1.95 b | 3.9 c | 62.5 d | 1.95 # |
| Enterococcus faecalis | 2000 a | 7.8 b | 7.8 b | 250 c | 0.24 # |
| Bacillus cereus | 500 a | 1.95 b | 3.9 c | 62.5 d | 0.98 # |
| Streptococcus pneumoniae | 125 a | 31.3 b | 62.5 c | 62.5 c | 0.24 # |
| Streptococcus pyogenes | 250 a | 31.3 b | 62.5 c | 1000 d | 0.24 # |
| Streptococcus mutans | 250 a | 125 b | 125 b | 2000 c | 0.98 # |
| Gram-negative bacteria | |||||
| Helicobacter pylori | 15.6 a | 7.8 b | 7.8 b | 62.5 c | 0.98 $ |
| Salmonella Typhimurium | >2000 | >2000 | >2000 | >2000 | 0.06 § |
| Escherichia coli | >2000 | >2000 | >2000 | >2000 | 0.02 § |
| Proteus mirabilis | >2000 | >2000 | >2000 | >2000 | 0.03 § |
| Klebsiella pneumoniae | >2000 | >2000 | >2000 | >2000 | 0.12 § |
| Pseudomonas aeruginosa | >2000 | >2000 | >2000 | >2000 | 0.49 § |
| Yeasts | |||||
| Candida albicans | 1000 a | 2000 b | 250 c | >2000 | 0.49 ß |
| Candida parapsilosis | 500 a | 2000 b | 250 c | 2000 b | 0.24 ß |
| Candida glabrata | 500 a | >2000 | 250 b | >2000 | 0.24 ß |
| Trichophyton rubrum | 125 a | 125 a | 31.3 b | 1000 c | 0.0049 & |
| Trichophyton mentagrophytes | 125 a | 31.3 b | 31.3 b | 250 c | 0.0012 & |
# vancomycin; $ ofloxacin; § ciprofloxacin; ß nystatin; & terbinafine; sample codes as in Table 1; * methicillin-resistant strain; different letters within rows indicate significant differences (p < 0.05); MIC, minimum inhibitory concentration.