[Antibacterial and bactericidal activity of tinidazole against anaerobic bacteria comparing with metronidazole (author's transl)].
Antibacterial activity of tinidazole (1-2-(ethylsulfonyl)-2-methyl-5-nitroimidazole) against anaerobic bacteria including Peptococcus, Peptostreptococcus, Eubacterium, Propionibacterium, Bacteroides and Fusobacterium was studied by agar dilution method comparing with metronidazole. In addition to this work, bactericidal effect of tinidazole and metronidazole against P. prevotii, B. fragilis ss. fragilis and F. varium was examined by quantitative culture method after incubation in GAM broth containing of 4 MIC, 2 MIC, 1 MIC and 1/2 MIC of both drugs against each of three strains for 1, 3, 6, 12 and 24 hours. All the strains of Peptococcus and Peptostreptococcus including P. anaerobius, P. saccharolyticus, P. prevotii and Ps. anaerobius and others were susceptible to a concentration of 6.25 mcg/ml of this drug. A concentration of 3.13 mcg/ml inhibited all strains of Bacteroides including B. fragilis ss. fragilis (12 strains), ss. vulgatus (5 strains), ss. thetaiotaomicron (4 strains) and ss. distasonis (2 strains). To this concentration all strains of Fusobacterium including F. varium (20 strains), F. mortiferum (2 strains) and other Fusobacterium sp. (5 strains) were susceptible. On the contrary, Propionibacterium acnes (6 strains) was resistant to 100 mcg/ml or more of tinidazole and metronidazole. The antibacterial activity of tinidazole was stronger against Bacteroides than that of metronidazole, while almost equal against Peptococcus, Peptostreptococcus, Eubacterium and Fusobacterium. Tinidazole was bactericidal against F. varium in a concentration of 2 MIC till 24 hours of incubation but did not show such an activity on B. fragilis ss. fragilis in same concentration even after 12 hours of incubation. On the other hand, metronidazole was bactericidal against B. fragilis ss. fragilis while was not against F. varium. Against P. prevotii bactericidal activity of both drugs was similar. Tinidazole as well as metronidazole is an excellent chemotherapeutic agent against anaerobic bacteria excluding Propionibacterium acnes and Bifidobacterium adolescentis.
D000191:Actinomycetaceae / Q000187:drug effects; D001419:Bacteria / Q000187:drug effects*; D001439:Bacteroides / Q000187:drug effects; D005051:Eubacterium / Q000187:drug effects; D005673:Fusobacterium / Q000187:drug effects; D008795:Metronidazole / Q000494:pharmacology*; D009593:Nitroimidazoles / Q000494:pharmacology*; D010460:Peptococcus / Q000187:drug effects; D010462:Peptostreptococcus / Q000187:drug effects; D011424:Propionibacterium / Q000187:drug effects; D014011:Tinidazole / Q000494:pharmacology*; D014678:Veillonella / Q000187:drug effects; D045854:Veillonellaceae
D009593:Nitroimidazoles; D014011:Tinidazole; D008795:Metronidazole