サルファ剤とTrimethoprim の協力作用-in vitro抗菌作用について-
1973 年 21 巻 2 号 p. 77-87
詳細
1973 年 21 巻 2 号 p. 77-87
The presence of anin vitro synergistic effect in the combination of sulfonamides and trimethoprim was investigated using two-fold agar plate dilution method recommended by the Japan Society of Chemotherapy. Each test material was cultured in MUELLER-HINTON broth overnight, and one loopful of an appropriate diluent (100 times dilution for gram-positive bacteria and 1000 times dilution for gram-negative rods) was inoculated into MUELLER-HINTON agar plate enriched with 7.5% lysed horse blood and containing increasing levels of test drugs.
In both sulfamethoxazole-sensitive and-resistant cultures a definite synergistic effect was observed, and in sulfonamide-resistant cultures much lower MIC values of sulfamethoxazole in combination were noted as compared with those of the single use of sulfonamide, whereas the decrease in the MIC values of trimethoprim in combination was not so significant chiefly due to the high antibacterial activity of trimethoprim. The combination was ineffective againstPseudomonas.
In spite of the relatively low activity of sulfadimethoxine, the combination of this and trimethoprim showed nearly the same MIC values as sulfamethoxazole- and sulfamonomethoxine-combination.
The potentiation of the activity of sulfonamide by trimethoprim was also confirmed in the growth curves of Escherichia coli culture with and without either of sulfonamide or trimethoprim and the combinations.
