CRITERION™ STAPH SELECTIVE AGAR

Cat. no. C7000 CRITERION™ Staph Selective Agar 202gm
Cat. no. C7001 CRITERION™ Staph Selective Agar 500gm
Cat. no. C7002 CRITERION™ Staph Selective Agar 2kg
Cat. no. C7003 CRITERION™ Staph Selective Agar 10kg
Cat. no. C7004 CRITERION™ Staph Selective Agar 50kg

INTENDED USE

Hardy Diagnostics CRITERION™ Staph Selective Agar is a selective medium used for the isolation and differentiation of pathogenic staphylococci.

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

Staph Selective Agar is an agar medium used for the selective isolation and differentiation of pathogenic staphylococci. The formulation contains a lower concentration of salt (4.0%) than Mannitol Salt Agar (7.5%). The lower salt concentration enhances the growth of most staphylococci. However the addition of selective agents is required to inhibit gram-negative and non-pathogenic staphylococci. The medium also contains bromcresol purple indicator which imparts a violet color to the prepared medium. Pathogenic staphylococci produce yellow colonies surrounded by yellow zones in a violet background.

FORMULA

Gram weight per liter: 101.0gm/L
Sodium Chloride 40.0gm
Selective Agents 14.0gm
Pancreatic Digest of Casein 10.0gm
Peptic Digest of Animal Tissue 10.0gm
Mannitol 10.0gm
Beef Extract 2.0gm
Bromcresol Purple 2.0mg
Agar 15.0gm

Final pH 7.4 +/- 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 bluish-beige.

Store the prepared culture media at 2-8ºC.

PRECAUTIONS

METHOD OF PREPARATION FOR DEHYDRATED CULTURE MEDIA

1. Suspend 101.0gm of the dehydrated culture media in 1 liter of distilled or deionized water.

2. Heat to boiling and mix to dissolve completely.

3. Sterilize in the autoclave at 121ºC. for 15 minutes.

4. Dispense into sterile containers as desired.

PROCEDURE AND INTERPRETATION OF RESULTS

For information on procedures and interpretation of results, cosult listed references.

LIMITATIONS

Additional serological and biochemical tests are required for complete identification, please see listed references for more information.(1-3)

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
Staphylococcus aureus
ATCC ® 25923
A 24-48hr 35°C Aerobic Good growth; yellow colonies
Staphylococcus epidermidis
ATCC ® 12228
A 24-48hr 35°C Aerobic Poor growth; clear colonies
Escherichia coli
ATCC ® 25922
B 24-48hr 35°C Aerobic Inhibited

User Quality Control

PHYSICAL APPEARANCE

CRITERION™ Staph Selective Agar powder should appear homogeneous, free-flowing, and bluish-beige in color. The prepared media should appear clear to slightly opalescent, and violet in color.

REFERENCES

1. Jorgensen., et al. Manual of Clinical Microbiology, American Society for Microbiology, Washington, D.C.

2. Vanderzant, Carl. 1992. Compendium of Methods For the Microbiological Examination of Foods, 3rd ed. American Public Health Association, Washington, D.C.

3. Marshall, R.T., et al. 1992. Standard Methods for the Examination of Dairy Products, 16th ed. American Public Health Association, Washington, D.C.


ATCC is a registered trademark of the American Type Culture Collection.

062116gr