HEART INFUSION Agar

Cat. no. Q59 Heart Infusion Agar, 20x125mm Tube, 20ml 20 tubes/box

INTENDED USE

Hardy Diagnostics Heart Infusion Agar is a general purpose growth medium. It is recommended for the cultivation of nutritionally fastidious microorganisms and as a basal medium with a variety of applications.

SUMMARY

Heart Infusion Agar can be used as the base in various formulations. The medium can be used to determine hemolytic reactions, as a base in carbohydrate fermentation tests, and for the mass cultivation of microorganisms in the preparation of vaccines. (2,3,6) Heart Infusion Media have also been specified for the isolation of Vibrio cholerae and Vibrio species. (4,5) The deep agar fill can be used an oxygen gradient to determine the oxygen requirements of the inoculum by observing where in the tube the growth is prominant.

A medium containing meat infusion was one of the first media used for the cultivation of bacteria. Huntoon prepared a "hormone" broth using fresh beef heart and peptone. (7) He found that the medium, without enrichments, could support the growth of a variety of microorganisms, including nutritionally fastidious organisms, such as, meningococci and pneumococci. (7) Hardy Diagnostics Beef Heart Infusion is an improved revision to this original formula. It contains beef heart infusion and peptones, which provide the nitrogen, vitamins, and carbon source to meet the nutritional growth requirements of a variety of organisms. Yeast Extract is added to the medium to provide additional vitamins to stimulate organism growth. Sodium chloride is added to the formulation to maintain osmotic balance in the medium.

FORMULA

Ingredients per liter of deionized water:*

Agar 14.0gm
Pancreatic Digest of Casein 9.0gm
Peptic Digest of Animal Tissue 5.0gm
Sodium Chloride 5.0gm
Yeast Extract 4.0gm
Beef Heart Infusion 2.0gm

Final pH 7.4 +/- 0.2 at 25ºC.

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

STORAGE AND SHELF LIFE

Storage: Upon receipt store at 2-30ºC. away from direct light. Media should not be used if there are any signs of deterioration (shrinking, cracking, or discoloration), contamination, or if the expiration date has passed. Product is light and temperature sensitive; protect from light, excessive heat, moisture, and freezing.

PRECAUTIONS

PROCEDURE

Specimen Collection: Consult listed references for information on specimen collection. (1,2,4,5,8) Infectious material should be submitted directly to the laboratory without delay and protected from excessive heat and cold. If there is to be a delay in processing, the specimen should be inoculated onto an appropriate transport media and refrigerated until inoculation.

As there are multiple uses of Heart Infusion Agar, consult listed references for specific testing procedures. (2,4-8)

Pour Plate Method:

1. Melt the agar by heating in boiling water.

2. Cool to 45ºC.

3. Add supplements as desired and pour into a sterile petri dish.

INTERPRETATION OF RESULTS

As there are multiple uses of Heart Infusion Broth, consult listed references for specific testing results. (2,4-8)

LIMITATIONS

Due to the various nutritional requirements of some organisms, occasional isolates may be encountered which fail to grow or grow poorly on this medium.

MATERIALS REQUIRED BUT NOT PROVIDED

Standard microbiological supplies and equipment such as loops, other culture media, swabs, applicator sticks, incinerators, and incubators, etc., as well as serological and biochemical reagents, are not provided.

QUALITY CONTROL

Test Organisms Inoculation Method* Incubation Results
Time Temperature Atmosphere
Escherichia coli
ATCC ® 25922**
A 24-48hr 35°C Aerobic Growth
Staphylococcus aureus
ATCC ® 25923**
A 24-48hr 35°C Aerobic Growth
Streptococcus epidermidis
ATCC ® 12228
A 18-24hr 35°C Aerobic Growth

** Recommended QC strains for User Quality Control according to the CLSI document M22 when applicable.

User Quality Control

PHYSICAL APPEARANCE

Heart Infusion Agar should appear clear, slightly opalescent and light amber in color with no precipitate, chips or debris.

REFERENCES

1. Anderson, N.L., et al. Cumitech 3B; Quality Systems in the Clinical Microbiology Laboratory, Coordinating ed., A.S. Weissfeld. American Society for Microbiology, Washington, D.C.

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

3. Atlas, R.M. 2010. Handbook of Microbiological Media, 4th ed. CRC Press, Inc., Boca Raton, FL.

4. APHA Technical Committee on Microbiological Methods for Foods. Compendium of Methods for the Microbiological Examination of Foods, APHA, Washington, D.C.

5. U.S. Food and Drug Administration. Bacteriological Analytical Manual. AOAC, Arlington, VA. www.fda.gov/Food/ScienceResearch/LaboratoryMethods/BacteriologicalAnalyticalManualBAM/default.htm

6. MacFaddin, J.F. 1985. Media for Isolation, Cultivation, Identification, Maintenance of Bacteria, Vol. I. Williams & Wilkins, Baltimore, MD.

7. Huntoon, F.M. 1918. "Hormone" Medium. A simple medium employable as a substitute for Serum Medium. The Journal of Infectious Disease. 23:169-172.

8. Isenberg, H.D. Clinical Microbiology Procedures Handbook, Vol. I, II & III. American Society for Microbiology, Washington, D.C.


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

030116gr