Gentamicin-Based Medium for the Isolation of Group D Streptococci and Application of the Medium to Water Analysis †

摘要: Gentamicin-thallous-carbonate (GTC) medium contained (per liter): 40.0 g of Trypticase soy agar, 5.0 KH2PO4, 2.0 NaHCO2, 1.0 glucose, esculin, 0.5 thallous acetate (TA), ferric citrate, 0.75 ml Tween 80, and 2.5 mg gentamicin sulfate. The NaHCO3 (20 a 10% solution that had been heated to boiling) was added after sterilization the basal medium. spread plate technique used compare GTC agar with Pfizer selective enterococcus, TA, KF agars by using sewage as well bovine swine fecal samples. Significantly greater numbers group D streptococci were recovered on than enterococcus or agars, within over all Higher counts also obtained TA but differences not statistically significant. percentage false positives about same for four media. Samples riverwater plated GTC, significantly higher recoveries agar. superior other media examined primarily because increased Streptococcus bovis S. equinus; advantages large colony size short (24-h) incubation period. from 13% 0% agars; therefore, confirmation would be necessary when is some types environmental