Table 3.
The OD of LYS, AZM, and their combinations with PIP/SBT on the mature biofilms of MRSA.
| Groups | MRSA 31 | MRSA 33 | MRSA 62 | |||
|---|---|---|---|---|---|---|
| Values | Percentage (%) | Values | Percentage (%) | Values | Percentage (%) | |
| Control | 0.658 ± 0.0877 | 100.0 | 0.499 ± 0.0927 | 100.0 | 0.685 ± 0.0843 | 100.0 |
| LYS | 0.407 ± 0.0183 | 61.9∗ | 0.585 ± 0.0640 | 117.2 | 0.753 ± 0.0959 | 109.9 |
| AZM | 0.749 ± 0.0400 | 113.8 | 0.592 ± 0.0755 | 118.6 | 0.676 ± 0.0447 | 98.7 |
| PIP/SBT | 0.631 ± 0.0490 | 95.9 | 0.464 ± 0.0245 | 93.0 | 0.753 ± 0.0608 | 109.9 |
| A: PIP/SBT+LYS | 0.425 ± 0.0217 | 64.6∗ | 0.314 ± 0.0212 | 62.9 | 0.629 ± 0.0436 | 91.8 |
| B: PIP/SBT+AZM | 0.596 ± 0.0742 | 90.6 | 0.371 ± 0.0390 | 74.3 | 0.455 ± 0.0938 | 66.4 |
| Comparison between different groups | ||||||
| A1: A and LYS | — | 104.4 | — | 53.7 | — | 83.5∗∗ |
| B1: B and AZM | — | 146.4 | — | 63.4∗ | — | 60.4∗ |
| A2: A and PIP/SBT | — | 56.7 | — | 53.0∗ | — | 93.0∗∗ |
| B2: B and PIP/SBT | — | 94.5 | — | 80.0∗∗ | — | 60.4 |
The values of OD are shown in mean ± standard deviation (SD). The percentage was defined as (OD value of the treatment group/OD value of the control) × 100%. MRSA 31, MRSA 33, and MRSA 62 represented three different clinical isolates. ∗P < 0.05, ∗∗P < 0.01, and ∗∗∗P < 0.001 compared with the control. MRSA: methicillin-resistant Staphylococcus aureus; OD: optical density; MTT: methylthiazolyldiphenyl-tetrazolium bromide; LYS: lysozyme; AZM: azithromycin; PIP/SBT: piperacillin/sulbactam; –: not tested.