Table 3.
Cytotoxicity (IC50 [µg/mL]) and selectivity indexes
| Peptide | IC50 | Selectivity index (SI) | ||||||
|---|---|---|---|---|---|---|---|---|
| E. faecium | S. aureus | K. pneumoniae | A. baumannii | P. aeruginosa | K. aerogenes | C. glabrata | ||
| 1M | 4.33 ± 1.12 | 0.27 | 0.27 | - | - | - | - | - |
| 2M | 32.49 ± 4.84 | 1.02 | 2.03 | - | 0.06 | 0.25 | 0.06 | 0.13 |
| 3M | 237.60 ± 31.18 | 7.43 | 3.71 | - | 0.46 | 1.86 | 0.93 | 0.46 |
| 4M | 252.20 ± 36.68 | 15.76 | 7.88 | - | 0.49 | 0.99 | 0.99 | 0.49 |
| 1P | 1.74 ± 0.49 | 0.44 | - | - | - | - | - | - |
| 2P | 10.27 ± 1.59 | 1.28 | 2.57 | 0.08 | 0.16 | 0.64 | 0.32 | 0.64 |
| 3P | 45.40 ± 20.45 | 5.68 | 5.68 | 1.42 | 0.71 | 1.42 | 5.68 | 0.71 |
| 4P | 126.80 ± 27.26 | 31.70 | 15.85 | 3.96 | 1.98 | 3.96 | 15.85 | 1.98 |
| 1S | 8.34 ± 1.07 | - | - | - | - | - | - | - |
| 2S | 4.33 ± 0.79 | 1.08 | 2.17 | 0.07 | 0.14 | 0.03 | 0.14 | 0.54 |
| 3S | 88.51 ± 4.72 | 22.13 | 22.13 | 11.06 | 2.77 | 5.53 | 22.12 | 11.06 |
| 4S | 155.34 ± 11.20 | 38.84 | 19.42 | 19.42 | 9.71 | 19.42 | 38.83 | 9.71 |
| 1Mq | 24.81 ± 3.88 | 0.78 | 0.78 | - | 0.19 | 0.19 | 0.10 | 0.78 |
| 2Mq | 258.90 ± 35.07 | 2.02 | 2.02 | - | - | - | - | 0.51 |
| 3Mq | >512 | 2.00 | - | - | - | - | - | - |
| 4Mq | >512 | >4.00 | - | - | - | - | ||
| 1Pq | 19.25 ± 9.34 | 1.20 | 1.20 | 0.04 | 0.30 | - | 0.08 | 2.41 |
| 2Pq | 99.62 ± 9.65 | 6.23 | 6.23 | 0.19 | 0.78 | 0.19 | 0.19 | 1.56 |
| 3Pq | >512 | >16.00 | >2.00 | - | - | - | - | |
| 4Pq | >512 | >16.00 | >1.00 | - | - | - | - | |
| 1Sq | 14.13 ± 0.39 | 3.53 | 1.77 | - | - | - | - | 3.53 |
| 2Sq | 78.57 ± 5.49 | 4.91 | 9.82 | 0.61 | 1.23 | - | 1.23 | 4.91 |
| 3Sq | 474.64 ± 29.06 | 29.67 | 7.42 | 1.85 | 3.71 | 0.93 | 7.42 | 3.71 |
| 4Sq | >512 | >32.00 | >8.00 | >2.00 | >2.00 | >1.00 | >8.00 | >1.00 |
| BAC | 11.70 ± 0.76 | 2.88 | 2.88 | 0.72 | 0.72 | 0.36 | 0.72 | 2.88 |
BAC benzalkonium chloride
*Bolded values refer to compounds with MIC ≤ 32 µg/mL