Abstract
A study was undertaken on the in vitro and in vivo antibacterial activities of enduracidin, a basic, peptide antibiotic substance extracted from Streptomyces fungicidicus No. B 5477, and the following was observed.
1. Enduracidin was found to have a high antibacterial activity against Gram-positive cocci and bacilli, but no activity was observed against Gramnegative bacilli. No cross-resistance with other antibiotics was observed.
2. The antibacterial activity of enduracidin was not affected by the pH in a range of 6-8 and nor was influenced by the addition of serum; the activity, however, was considerably affected by the size of inoculum.
3. Enduracidin was found to be therapeutically more effective against experimental Staphylococcus aureus or Staphylococcus hemolyticus infection in mice than penicillin G, and most effective by the intraperitoneal route of administration. Further, the therapeutic activity of enduracidin varied with the route of inoculation in the case of staphylococcal infection.
