In-vitro postantibiotic effects of miocamycin and erythromycin on gram-positive cocci.

SummaryThe capability of miocamycin to induce a postantibiotic effect (PAE) on a Group A Streptococcus β-haemolyticus clinical isolate and on Staphylococcus aureus ATCC 29213 has been studied. Erythromycin was chosen as a reference molecule. The exposure time to antibiotics was 90 min.The removal technique of the antibiotic agents consisted of a 1:200 dilution in cultural broth.Miocamycin displayed a PAE of 2h 30min in relation to the minimum inhibitory concentration (MIC) of Streptococcus and a PAE of 2h 30min in relation to the MIC of Staphylococcus. The PAE value lasting longer than the others was of 5h 40min towards Streptococcus and of 4h 18min towards Staphylococcus at a concentration eightfold the MIC.Erythromycin showed a PAE of 1h 36min in relation to the MIC of Streptococcus and a PAE of 1h 30min in relation to the MIC of Staphylococcus. The PAE value lasting longer than the others was of 3h 15min against Streptococcus and of 2h 30min against Staphylococcus at a concentration eightfold the MIC.I...