Sabouraud agar

Sabouraud Agar is a type of agar medium used extensively in microbiology for the cultivation of fungi, particularly dermatophytes. It was created by Raymond Sabouraud in 1892, primarily for the study of skin fungal pathogens. The medium's low pH (approximately 5.6) inhibits the growth of most bacteria while allowing fungi to thrive, making it an ideal environment for mycological studies.

Composition

Sabouraud Agar consists of:

• Peptones: Provide nitrogen and vitamins necessary for fungal growth.
• Glucose: Serves as the primary energy source.
• Agar: A gelatinous substance that provides the medium's solid structure.
• Adjusted pH: Typically around 5.6, achieved through the addition of acids or buffers.

Uses

The primary use of Sabouraud Agar is in the isolation, cultivation, and identification of fungi, including both yeasts and filamentous fungi. It is particularly useful in the diagnosis of fungal infections in clinical specimens. The medium can also be supplemented with antibiotics to inhibit bacterial growth or with compounds like Cycloheximide to suppress the growth of saprophytic fungi, thus facilitating the isolation of pathogenic fungi.

Variants

Several variants of Sabouraud Agar exist, tailored for specific microbiological needs. These include:

• Sabouraud Dextrose Agar with Chloramphenicol
• Sabouraud Dextrose Agar with Cycloheximide
• Sabouraud Chloramphenicol Cycloheximide Agar

Each variant includes additives that either inhibit bacterial growth or select for specific types of fungi.

Limitations

While Sabouraud Agar is highly effective for the cultivation of fungi, it does have limitations. Its acidic pH may inhibit the growth of some fungi, and the medium does not differentiate between different fungi species. Further identification tests are necessary to accurately identify the fungal species present.

See Also

• Microbial culture
• Dermatophyte Test Medium
• Mycology

Sabouraud agar gallery

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  Trichophyton rubrum var. rodhaini
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  Sporothrix schenckii
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  Candida albicans
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  Trichophyton terrestre