The In Vitro Activity of Trospectomycin against Anaerobic Bacterìa

The authors evaluated the activity of trospectomycin, a new aminocyclitol which is characterized by good antibacterial and broad spectrum activity, in comparison with clindamycin and ampicillin on a sample of recent isolates: Bacteroides fragilis (15 strains), Bacteroides urealyticus (5 strains), Bcateroides vulagatus (5 strains), Bacteroides spp. (15 strains), Prevotella melaninogenica (6 strains), Porphyromonas asaccharolytica (7 strains, Mobiluncus spp. (3 strains), Peptococcus niger (3 strains), Petococcus variabilis (9strains), Peptococcus spp.(30 strains),Peptococcus asaccharalyticus (3 strains), Peptococcus spp. (25 strains) and Proprionibacterium spp. (7strains). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for all strains by microtiter serial dilutions in Wilkins-Chalgren broth in an anaerobic chamber in an atmosphere of 10% H2, 10% CO2, 80% N2) All the drugs tested exert their activity against Gram-positive and Gram-negative anaerobic isolates. In particular, trospectomycin is quite active against Gram-positive cocci (MIC90=4-8mg/l), Gram-negative rods (MIC90=8-16mg/l), Gram-positive rods (MIC90=4mg/l) and Mobiluncus spp. (MIC90=0.5mg/l).