Algae & Fungi – Yeast & Molds
HiCrome™ Candida Differential Agar is recommended for rapid isolation and identification of Candida species from mixed cultures in clinical and non-clinical samples.
Ingredients Gms / Litre
Peptone, special 15.000
Yeast extract 4.000
Dipotassium hydrogen phosphate 1.000
Chromogenic mixture 7.220
Final pH ( at 25°C) 6.3±0.2
**Formula adjusted, standardized to suit performance parameters
Suspend 42.72 grams in 1000 ml distilled water. Heat to boiling to dissolve the medium completely. DO NOT AUTOCLAVE. Cool to 45-50°C. Mix well and pour into sterile Petri plates.
Principle And Interpretation
Perry and Miller (3) reported that Candida albicans produces an enzyme b -N-acetyl- galactosaminidase and according to Rousselle et al (4) incorporation of chromogenic or fluorogenic hexosaminidase substrates into the growth medium helps in identification of C.albicans isolates directly on primary isolation. HiCrome™ Candida Differential Agar is a selective and differential medium, which facilitates rapid isolation of yeasts from mixed cultures and allows differentiation of Candida species namely C.albicans, C.krusei, C.tropicalis and C.glabrata on the basis of colouration and colony morphology. On this medium results are obtained within 48 hours and it is useful for the rapid and presumptive identification of common yeasts in Mycology and Clinical Microbiology Laboratory. Peptone special and yeast extract provides nitrogenous, carbonaceous compounds and other essential growth nutrients. Phosphate buffers the medium well. Chloramphenicol suppresses the accompanying bacterial flora. C.albicans appear as light green coloured smooth colonies, C.tropicalis appear as blue to metallic blue coloured raised colonies. C.glabrata colonies appear as cream to white smooth colonies, while C.krusei appear as purple fuzzy colonies.
Type of specimen
Clinical samples – skin scrapings, urine.
Specimen Collection and Handling
For clinical samples follow appropriate techniques for handling specimens as per established guidelines (3,4). After use, contaminated materials must be sterilized by autoclaving before discarding.
Warning and Precautions
In Vitro diagnostic Use only. Read the label before opening the container. Wear protective gloves/protective clothing/eye protection/ face protection. Follow good microbiological lab practices while handling specimens and culture. Standard precautions as per established guidelines should be followed while handling clinical specimens. Safety guidelines may be referred in individual safety data sheets.
1. Variations in colour intensity may be observed for Candida isolates depending on the presence of enzymes.
2. Other Candida species may produce light mauve coloured colonies which is also produced by other yeast cells. This must be confirmed by further biochemical tests.
3. Other filamentous fungi also exhibit colour on this medium.