Cat. no. U70 TSB, DS, USP, 250ml Square Polycarbonate Bottle, 100ml 12 bottles/box
Cat. no. U205 TSB, DS, USP, 180ml Wide Mouth Jar, 50ml 12 jars/box
Cat. no. U225 TSB, DS, USP, 4oz. Glass Bottle, 25ml 12 bottles/box
Cat. no. U350 TSB, DS, USP, 500ml Polycarbonate Bottle, 150ml 10 bottles/box


Hardy Diagnostics Tryptic Soy Broth (TSB), Double Strength (DS) is recommended for use as a general purpose medium for the isolation and cultivation of a wide variety of bacteria and fungi.

This product is not intended to be used for the diagnosis of human disease.


Tryptic Soy Broth is widely used for the isolation of bacteria from clinical specimens, supporting the growth of a majority of pathogenic bacteria. This medium may be used for preparing dilutions of organism for colony counts, preparing standard inocula, and antibiotic sensitivity testing for both fastidious and non-fastidious microorganisms. Tryptic Soy Broth is also recommended for use in sterility testing for the detection of contamination with low incidence fungi and aerobic bacteria. (7) The concentration of ingredients in Tryptic Soy Broth, DS is critical to the media performance. When used to detect organisms in samples, the volume of sample being tested must be equal to the initial volume of TSB, DS. This will ensure that the ingredients in the media will be at the correct concentration after the addition of the test sample.

Tryptic Soy Broth, also known as Soybean-Casein Digest, conforms to the formula given by the U.S. Pharmacopeia. (7) It was originally developed for testing the sensitivity of pneumococci and other microorganisms to sulfonamides without adding blood or serum to the medium. (1) Hamilton and Spink in the early 1950's, reported the use of Tryptic Soy Broth as suitable for the growth of aerobic and facultative microorganisms including Brucella species. (5) Later, Garrison and Hedgecock both demonstrated the use of this medium to promote the growth of pathogenic fungi. (11)

This medium contains digests of soybean meal and casein, which provide amino acids and other nitrogenous substances, making it a highly nutritious medium for a variety of organisms, including most pathogenic bacteria. Sodium chloride is added to maintain the osmotic equilibrium. Dextrose is incorporated as an energy source. The dipotassium phosphate is included in the formulation as a buffer to maintain the pH.


Ingredients per 500ml of deionized water:*

Pancreatic Digest of Casein 17.0gm
Sodium Chloride 5.0gm
Papaic Digest of Soybean Meal 3.0gm
Dextrose 2.5gm
Dipotassium Phosphate 2.5gm

Final pH 7.3 +/- 0.2 at 25ºC.

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


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



Specimen Collection: Consult listed references for information on specimen collection. (2,4,7-10) 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.

Method of Use: The amount of sample added to Tryptic Soy Broth, DS is critical to the performance of the media. The volume of sample being tested must be equal to the initial volume of TSB, DS. For example, if a 50ml volume of TSB Double Strength formula is being utilized, then 50ml of sample should be added to the media.

Inoculate the medium as soon as possible after the specimen has been collected. Incubate with caps loosened, in the appropriate atmospheric environment and incubation temperature for 18-24 hours, or up to seven days. Refer to listed references for additional procedures using this media. (2-4,7-10)


Consult listed references for interpretation criteria and further biochemical testing of growth in Tryptic Soy Broth. (2-4,7-10)



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.


Test Organisms Inoculation Method* Incubation Results
Time Temperature Atmosphere
Aspergillus brasiliensis formerly A. niger
ATCC ® 16404
J** 1-5 days 20-25°C Aerobic Growth
Candida albicans
ATCC ® 10231
J** 1-5 days 20-25°C Aerobic Growth
Bacillus subtilis
ATCC ® 6633
J** 1-3 days 30-35°C Aerobic Growth
Pseudomonas aeruginosa
ATCC ® 9027
J** 1-3 days 30-35°C Aerobic Growth
Staphylococcus aureus
ATCC ® 6538
J** 1-3 days 30-35°C Aerobic Growth
Bacillus subtilis
ATCC ® 6633
J** 1-3 days 20-25°C Aerobic Growth

** Before inoculation, aseptically add equivalent fill amounts of sterile deionized water to each container. This will bring the ingredients in the media to the correct concentration.

User Quality Control


Tryptic Soy Broth, Double Strength should appear clear, and medium amber in color.


1. Anderson, N.L., et al. 2005. 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. Tille, P., et al. Bailey and Scott's Diagnostic Microbiology , C.V. Mosby Company, St. Louis, MO.

4. American Public Health Association. Standard Methods for the Examination of Water and Wastewater, APHA, Washington, D.C.

5. Spink, W.W. 1952. Amer. J. of Clin. Pathol. , 22:201.

6. Quality Assurance for Commercially Prepared Microbiological Culture Media , M22. Clinical and Laboratory Standards Institute (CLSI - formerly NCCLS), Wayne, PA.

7. The Official Compendia of Standards. 2012. USP-NF . United States Pharmacopeial Convention, Rockville, MD.

8. American Public Health Association. Standard Methods for the Examination of Dairy Products, APHA, Washington, D.C.

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

10. U.S. Food and Drug Administration. Bacteriological Analytical Manual. AOAC, Arlington, VA.

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

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