Assuntos
Ácidos e Sais Biliares/metabolismo , Ceco/microbiologia , Clostridium/metabolismo , Eubacterium/metabolismo , Intestinos/microbiologia , Streptococcus/metabolismo , Anaerobiose , Animais , Técnicas Bacteriológicas , Contagem de Células , Cromatografia em Camada Fina , Corynebacterium/metabolismo , Fusobacterium/metabolismo , Vida Livre de Germes , Glicina , Lactobacillus/metabolismo , Pasteurella/metabolismo , Ratos , TaurinaRESUMO
A selective agar medium (medium J(1)) is proposed for the quantitative enumeration of egg yolk-positive (EYP) and egg yolk-negative (EYN) Staphylococcus pyogenes from the digestive tract and feces of the rat. This medium, buffered at pH 5.0, is composed of acid casein hydrolysate and yeast extract with 7.5% sodium chloride, 1.6% sodium pyruvate, 0.0008% 2,3,5-triphenyltetrazolium chloride (TTC), and 6% egg yolk emulsion. Inoculation is by the pour-plate method and incubation is at 38 C in a water-jacketed incubator for 36 hr. Colonies of S. pyogenes reduce TTC; EYP strains are surrounded by a halo of opacity; and EYN strains may be surrounded by a red halo, but no opacity. Small, white colonies of S. epidermidis may develop, but Micrococcus, and all other groups of Staphylococcus recognized in the rat intestinal flora, are inhibited. Other bacterial genera, notably Bacillus, Corynebacterium, Proteus, and Streptococcus, are also inhibited.
