Isolation Methods PDF

ISOLATION METHODS Culture Media Few types of standard media are needed for primary isolation. -can be poured in petri dishes or large test tubes. - can be sealed with tape or parafilm or sealed in semipermeable bag to minimize dehydration and prevent spread of fungal spores. -tubed med...

ISOLATION METHODS Culture Media Few types of standard media are needed for primary isolation. -can be poured in petri dishes or large test tubes. - can be sealed with tape or parafilm or sealed in semipermeable bag to minimize dehydration and prevent spread of fungal spores. -tubed media – safer to handle and less susceptible to drying ISOLATION METHODS Incubation -Incubate at room temp, 40-50% humidity. -If dimorphic: 37°C - Maintained 4-6 weeks, examine twice weekly. ISOLATION METHODS Media 1. Sabourad dextrose agar Primary isolation and maintenance of culture Addition of thiamine enhances the growth of dermatophytes 2. Mycosel (BBL) or Mycobiotic (difco) Isolation of pathogenic fungi from contaminated material chloramphenicol to inhibit bacterial growth, and cycloheximide to inhibit saprophytic fungi and ISOLATION METHODS Media 3. Brain heart infusion (BHI) blood agar – for yeast phase of systemic fungi at 35°C. Fastidious dimorphic fungi. Blood inhibits conidiation. more enriched than Sab-Dex. For recovery of H. capsulatum. ISOLATION METHODS Media 4. SABHI blood agar – Recovery of Blastomyces and Histoplasma for yeast phase Fastidious dimorphic fungi. Blood inhibits conidiation. ISOLATION METHODS Media 5. Yeast extract agar Identidfication of Blastomyces, Coccidiodes and Histoplasma 6. DTM (Dermatophyte Test Medium) Indicator medium for dermatophytes most saprophytes yeast and bacteria do not grow or produce no color change