[Safety evaluation of micronomicin VIII. Teratogenicity studies in rabbits after intravenous injection]

Micronomicin (MCR) is a new aminoglycoside antibiotic produced by Micromonospora sagamiensis var. nonreducans which was isolated from soil collected at Sagamihara City by Nara et al. This antibiotic shows a close similarity to gentamicin C components in physical and chemical properties. The antibacterial activity of MCR is broad-spectrum and almost equal to that of gentamicin C complex. MCR exhibits particularly high activity against Pseudomonas, Proteus, Klebsiella pneumoniae, Serratia, etc. as well as against some Pseudomonas aeruginosa strains resistant to gentamicin C1a. Teratogenicity studies of MCR in rabbits were carried out by intravenous injection for safety evaluation (Dose; 25, 50 mg/kg and 70 mg/kg). The results of studies are as follows. Fetal malformation attributable to MCR was not observed at any dose. There was no adverse effect on new borns at any dose.