Cultural characteristics

CULTURAL CHARACTERISTICS
  • Both yeast and mycelial forms can be cultivated if suitable media, temperature of incubation and carbon dioxide tenson are provided.
  • The organism grows slowly when the yeast phase is grown on media rich in protein and in an atmosphere enriched with CO2.
  • Several culture media have been used, but the most satisfactory were Sabouraud's dextrose agar enriched with 2.5% glycerol; brain heart infusion agar enriched with 10% horse blood; nutrient agar supplemented with 2% dextrose; mycobiotic agar and mycoplasma-like organism medium.
  • Growth on all media is very slow and appears after four to eight weeks of incubation at 25°C.
  • Colonies of the mycelial form are a yellowish/light brown to deep brown, convoluted, waxy and cauliflower-like.
  • In body tissues, the ability of H. farciminosum to convert from the mycelial form to the yeast form appears to be dependent on temperature and nutrition as well as the strain, However, in vitro, conversion of the mycelial form to the yeast form of H. farciminosum can be achieved by incubating at 35°C to 37°C.
  • Complete conversion to the yeast form is achieved only after four to five repeated serial transfers onto fresh media every eight days.
Last modified: Monday, 4 June 2012, 6:37 AM