Table 2.
Minimum bactericidal concentration (MBC) (mg/mL), minimum inhibitory concentration (MIC) (mg/mL), and MBC/MIC ratio for the antimicrobial agents and catechin against E. coli isolates.
| Bacteria | Effect | Rifampin | Tetracycline | Erythromycin | Clindamycin | Azithromycin | Vancomycin | Gentamycin | Catechin |
|---|---|---|---|---|---|---|---|---|---|
| Escherichia coli ATCC 25922 # | MBC | 8 | 32 | 32 | 8 | 8 | 64 | 4 | 2 |
| MIC | 4 | 16 | 8 | 4 | 4 | 16 | 2 | 1 | |
| MBC/MIC | 2(+) | 2(+) | 4(+) | 2(+) | 2(+) | 4(+) | 2(+) | 2(+) | |
| Escherichia coli ATCC 8739 # | MBC | 4 | 32 | 32 | 16 | 1 | 32 | 4 | 4 |
| MIC | 2 | 16 | 16 | 8 | 0.5 | 16 | 2 | 2 | |
| MBC/MIC | 2(+) | 2(+) | 2(+) | 2(+) | 2(+) | 2(+) | 2(+) | 2(+) | |
| Escherichia coli ATCC 43895 # | MBC | 8 | 32 | 16 | 8 | 16 | 16 | 4 | 2 |
| MIC | 4 | 16 | 8 | 4 | 8 | 8 | 2 | 1 | |
| MBC/MIC | 2(+) | 2(+) | 2(+) | 2(+) | 2(+) | 2(+) | 2(+) | 2(+) | |
|
Escherichia coli
(isolate 1) |
MBC | 32 | 32 | 32 | 32 | 2 | 32 | 8 | 4 |
| MIC | 16 | 8 | 4 | 4 | 0.5 | 8 | 4 | 1 | |
| MBC/MIC | 2(+) | 4(+) | 8(−) | 8(−) | 4(+) | 4(+) | 2(+) | 4(+) | |
|
Escherichia coli
(isolate 2) |
MBC | 16 | 32 | 16 | 32 | 2 | 32 | 8 | 4 |
| MIC | 8 | 4 | 4 | 4 | 1 | 8 | 4 | 1 | |
| MBC/MIC | 2(+) | 8(−) | 4(+) | 8(−) | 2(+) | 4(+) | 2(+) | 4(+) | |
|
Escherichia coli
(isolate 3) |
MBC | 16 | 32 | 32 | 32 | 1 | 16 | 8 | 4 |
| MIC | 8 | 8 | 4 | 4 | 0.5 | 2 | 4 | 1 | |
| MBC/MIC | 2(+) | 4(+) | 8(−) | 8(−) | 2(+) | 8(−) | 2(+) | 4(+) | |
|
Escherichia coli
(isolate 4) |
MBC | 32 | 64 | 32 | 32 | 1 | 32 | 8 | 4 |
| MIC | 16 | 4 | 8 | 8 | 0.5 | 8 | 4 | 1 | |
| MBC/MIC | 2(+) | 16(−) | 4(+) | 4(+) | 2(+) | 4(+) | 2(+) | 4(+) | |
|
Escherichia coli
(isolate 5) |
MBC | 16 | 64 | 32 | 32 | 1 | 32 | 8 | 4 |
| MIC | 8 | 4 | 8 | 2 | 0.5 | 8 | 4 | 1 | |
| MBC/MIC | 2(+) | 16(−) | 4(+) | 16(−) | 2(+) | 4(+) | 2(+) | 4(+) | |
|
Escherichia coli
(isolate 6) |
MBC | 16 | 32 | 16 | 32 | 2 | 64 | 4 | 4 |
| MIC | 8 | 4 | 4 | 8 | 1 | 16 | 1 | 1 | |
| MBC/MIC | 2(+) | 8(−) | 4(+) | 4(+) | 2(+) | 4(+) | 4(+) | 4(+) | |
|
Escherichia coli
(isolate 7) |
MBC | 32 | 32 | 64 | 32 | 2 | 64 | 16 | 4 |
| MIC | 8 | 8 | 8 | 2 | 1 | 8 | 8 | 1 | |
| MBC/MIC | 4(+) | 4(+) | 8(−) | 16(−) | 2(+) | 8(−) | 2(+) | 4(+) | |
|
Escherichia coli
(isolate 8) |
MBC | 64 | 32 | 32 | 32 | 4 | 32 | 32 | 4 |
| MIC | 8 | 8 | 4 | 4 | 1 | 16 | 16 | 1 | |
| MBC/MIC | 8(−) | 4(+) | 8(−) | 8(−) | 4(+) | 2(+) | 2(+) | 4(+) | |
|
Escherichia coli
(isolate 9) |
MBC | 64 | 32 | 32 | 32 | 2 | 32 | 4 | 2 |
| MIC | 16 | 8 | 8 | 4 | 1 | 8 | 2 | 0.5 | |
| MBC/MIC | 4(+) | 4(+) | 4(−) | 8(−) | 2(+) | 4(+) | 2(+) | 4(+) | |
|
Escherichia coli
(isolate 10) |
MBC | 64 | 32 | 32 | 32 | 4 | 64 | 4 | 2 |
| MIC | 32 | 8 | 4 | 4 | 1 | 16 | 2 | 0.5 | |
| MBC/MIC | 2(+) | 4(+) | 8(−) | 8(−) | 4(+) | 4(+) | 2(+) | 4(+) | |
|
Escherichia coli
(isolate 11) |
MBC | 64 | 32 | 16 | 32 | 2 | 16 | 8 | 4 |
| MIC | 32 | 8 | 4 | 4 | 0.5 | 4 | 2 | 1 | |
| MBC/MIC | 2(+) | 4(+) | 4(+) | 8(−) | 4(+) | 4(+) | 4(+) | 4(+) | |
|
Escherichia coli
(isolate 12) |
MBC | 64 | 32 | 64 | 32 | 4 | 32 | 8 | 4 |
| MIC | 32 | 8 | 8 | 4 | 1 | 8 | 2 | 1 | |
| MBC/MIC | 2(+) | 4(+) | 8(−) | 8(−) | 4(+) | 4(+) | 4(+) | 4(+) | |
|
Escherichia coli
(isolate 13) |
MBC | 64 | 32 | 16 | 16 | 2 | 32 | 8 | 4 |
| MIC | 32 | 4 | 8 | 4 | 0.5 | 8 | 4 | 1 | |
| MBC/MIC | 2(+) | 8(−) | 2(+) | 4(+) | 4(+) | 4(+) | 2(+) | 4(+) | |
|
Escherichia coli
(isolate 14) |
MBC | 16 | 64 | 32 | 32 | 2 | 32 | 8 | 4 |
| MIC | 8 | 32 | 4 | 4 | 1 | 4 | 4 | 1 | |
| MBC/MIC | 2(+) | 2(+) | 8(−) | 8(−) | 2(+) | 8(−) | 2(+) | 4(+) | |
|
Escherichia coli
(isolate 15) |
MBC | 32 | 64 | 32 | 32 | 1 | 32 | 8 | 4 |
| MIC | 16 | 32 | 4 | 4 | 0.5 | 16 | 4 | 1 | |
| MBC/MIC | 2(+) | 2(+) | 8(−) | 8(−) | 2(+) | 2(+) | 2(+) | 4(+) |
“#” means statistical data are unavailable. All the data were obtained from three independent experiments. For the MBC/MIC ratio, (+) bactericidal; (−) bacteriostatic.