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Published on: January 14, 2017
Timed bacteriostatic and bactericidal activities of selected antimicrobial agents against Bacteroides fragilis
Abstract:
The activities of selected antimicrobial agents were evaluated for bacteriostatic and bactericidal activities for a large number of clinically obtained strains of Bacteroides fragilis, with special reference to the incubation time of the microbes with the drugs. If the mode of action of a drug is categorized as bactericidal when the ratio of bactericidal concentration/bacteriostatic concentration is low (less than or equal to 4), and as bacteriostatic when high (greater than or equal to 8), during given periods of incubation, then clindamycin, minocycline and chloramphenicol appeared to be bacteriostatic, and cefoxitin, cefmetazole, latamoxef (moxalactam) and metronidazole bactericidal, when the incubation time was brief (6 hours). All these drugs acted bactericidally on most of the test strains, if the time of incubation was prolonged to 24 hours.
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