CRITERION™ CORN MEAL AGAR

Cat. no. C5490 CRITERION™ Corn Meal Agar 36gm
Cat. no. C5491 CRITERION™ Corn Meal Agar 500gm
Cat. no. C5492 CRITERION™ Corn Meal Agar 2kg
Cat. no. C5493 CRITERION™ Corn Meal Agar 10kg
Cat. no. C5494 CRITERION™ Corn Meal Agar 50kg

INTENDED USE

Hardy Diagnostics CRITERION™ Corn Meal Agar is recommended for use in the cultivation of fungi and for the inducement of chlamydospore formation by Candida albicans.

This dehydrated culture medium is a raw material intended to be used in the making of prepared media products, which will require further processing, additional ingredients, or supplements.

SUMMARY

CRITERION™ Corn Meal Agar is useful in the morphologic differentiation of many yeast-like organisms and in the cultivation of fungi. It suppresses vegetative growth of many fungi while stimulating sporulation.(1) Candida albicans forms chlamydospores on certain media and this production of chlamydospores is the most important diagnostic criterion for identifying C. albicans.(2) Corn meal has shown to be successful in stimulating the production of chlamydospores by C. albicans. Kelly and Funigeillo reported that enhanced chlamydospore formation by C. albicanscan be achieved by the addition of 1% Tween® 80.(3) Corn Meal Agar, with the addition of Tween® 80, may be the most accurate routine tool available for identifying C. albicans.(4)

CRITERION™ Corn Meal Agar consists of corn meal infusion and agar. Growth nutrients are provided by the infusion product.

FORMULA

Gram weight per liter:* 18.0gm/L
Corn Meal Infusion from Solids 2.0gm
Agar 15.0gm

Final pH 6.0 +/- 0.2 at 25ºC.

* Adjusted and/or supplemented as required to meet performance criteria.

STORAGE AND SHELF LIFE

Store the sealed bottle(s) containing dehydrated culture medium at 2-30ºC. Dehydrated culture medium is very hygroscopic. Keep lid tightly sealed. Protect dehydrated culture media from moisture and light. The dehydrated culture media should be discarded if it is not free-flowing or if the color has changed from its original yellow.

Store the prepared culture media at 2-8ºC.

PRECAUTIONS

METHOD OF PREPARATION FOR DEHYDRATED CULTURE MEDIA

1. Suspend 18.0gm of the dehydrated culture media in 1 liter of distilled or deionized water.

2. Heat to boiling to dissolve completely.

3. Add 10ml of Tween ® 80 if desired.

4. Autoclave at 121ºC. for 15 minutes.

PROCEDURE AND INTERPRETATION OF RESULTS

For information on procedures and interpretation of results, consult listed references or refer to the prepared media Instructions for Use (IFU) for Cat. No. W10.

LIMITATIONS

A non-selective and selective medium should be inoculated for isolation of fungi from potentially contaminated specimens.

Repeated subculturing of some Candida strains result in a loss of their ability to produce chlamydospores.

C. stellatoidea and C. tropicalis also produce chlamydospores on Corn Meal Agar with the addition of 1% Tween® 80.

MATERIALS REQUIRED BUT NOT PROVIDED

Standard microbiological supplies and equipment such as autoclaves, incinerators, and incubators, etc., are not provided.

QUALITY CONTROL

Test Organisms Inoculation Method* Incubation Results
Time Temperature Atmosphere
Candida albicans
ATCC ® 10231
C 24-72hr 15-30°C Aerobic Growth; hyphae, budding cells and chlamydospores seen
Aspergillus brasiliensis
formerly A. niger
ATCC ® 16404

C 24-72hr 15-30°C Aerobic Growth; no chlamydospores seen
Saccharomyces cerevisiae
ATCC ® 9763
C 24-72hr 15-30°C Aerobic Growth; no chlamydospores seen

User Quality Control

PHYSICAL APPEARANCE

CRITERION™ Corn Meal Agar powder should appear homogeneous, free-flowing, and yellow in color. The prepared media should appear clear, with a slight opalescence, and light amber in color.

REFERENCES

1. Tille, P., et al. Bailey and Scott's Diagnostic Microbiology, C.V. Mosby Company, St. Louis, MO.

2. Duncan, J. and J. Floeder. 1963. A comparison of media for the production of chlamydospores by Candida albicans. Am. J. Med. Tech.; 29:199-206.

3. Kelly, J.P. and F. Funigiello. 1959. Candida albicans: A study of media designed to promote chlamydospore production. J. Lab. & Clin. Med.; 53:807-809.

4. Fordon, M.A. and G.N. Little. 1963. Effective dehydrated media with surfactants for identification of Candida albicans. J. of Int. Soc. for Human and Animal Mycol.; 2:171-175.

5. Koneman, E.W., et al. Color Atlas and Textbook of Diagnostic Microbiology, J.B. Lippincott Company, Philadelphia, PA.

6. Campbell, M.C. and J.L. Stewart. 1980. The Medical Mycology Handbook, John Wiley and Sons, New York.

7. McGinnins. 1980. Laboratory Handbook of Medical Mycology, Academic Press, New York.


ATCC is a registered trademark of the American Type Culture Collection.
Tween is a registered trademark of ICI Americas, Inc.

051616gr