![]() Avoid overheating a medium with an acidic pH this may result in a soft medium.Antimicrobial agents added into a medium to inhibit bacteria may also inhibit certain pathogenic fungi.It does not promote the conidiation of filamentous fungi.SabHI agar yields a greater recovery of pathogenic fungi than either medium individually. ![]() SabHI Agar is formulated by combining Sabouraud Dextrose Agar and Brain Heart Infusion Agar. Aspergillus nidulans Greenish-blue with a whitish edge, yellow to brownish on reverse Trichosporon mucoides White to cream, yellowish, wrinkled Geotrichum candidum White to cream-colored, flat with aerial mycelium Modifications of Sabouraud Agar Typical Colony morphology of some fungi on SDA Fungi Colony morphology Aspergillus flavus Yellow-green, powdery, and pale yellowish on reverse Aspergillus niger The initial growth is white, becoming black later on giving “salt and pepper appearance” which results from darkly pigmented conidia borne in large numbers on conidiophores and reverse turning pale yellow Rhodotorula species pinkish-orangish creamy colonies Aspergillus fumigatus Blue-green, powdery and pale yellow on the reverse. Molds will grow as filamentous colonies of various colors. Yeasts will grow as creamy to white colonies. ![]() Additional procedures should be performed to confirm the findings. Examine plates for fungal colonies exhibiting typical color and morphology. Result and interpretation:Īfter sufficient incubation, SDA plates should show isolated colonies in streaked areas and confluent growth in areas of heavy inoculation. Cultures should be examined weekly for fungal growth and held for 4 – 6 weeks before being reported as negative.Incubate the plates at 25 – 30☌ in an inverted position (agar side up) with increased humidity.To process specimens, streak the specimen onto the medium with a sterile inoculating loop to obtain isolated colonies.Cool to 45 to 50☌ and pour into Petri dishes or tubes for slants.Heat with frequent agitation and boil for one minute to completely dissolve the medium.Suspend 65 gm of the medium in one liter of purified water.Mold colony with black pigmentation in SDA Composition of SDA Ingredients Gm/L Mycological peptone (enzymatic digest of casein and animal tissues) 10 gm Dextrose 40 gm Agar 15 gm pH adjusted to 5.6 at 25☌ Preparation of SDA Gentamicin is added to further inhibit the growth of gram-negative bacteria. The addition of antibiotics like chloramphenicol and/or tetracycline acts as broad-spectrum antimicrobials to inhibit the growth of a wide range of gram-positive and gram-negative bacteria. ![]() Sabouraud Dextrose Agar is comprised of enzymatic digest of casein and animal tissues which provide a nutritious source of amino acids and nitrogenous compounds for the growth of fungi and yeasts.ĭextrose is a fermentable carbohydrate incorporated in high concentrations as a carbon and energy source. Limitations of Sabouraud Agar Principle.Typical Colony morphology of some fungi on SDA. ![]()
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