FLUID THIOGLYCOLLATE MEDIA, USP

Cat. no. K84 Fluid Thioglycollate, USP, 20x125mm Tube, 15ml 20 tubes/box
Cat. no. K121 Fluid Thioglycollate, USP, 20x125mm Tube, 10ml 20 tubes/box
Cat. no. K212BX Fluid Thioglycollate, USP, 16x125mm Tube, 10ml 80 tubes
**ReadyRack
Cat. no. K282 Fluid Thioglycollate, USP, 16x125mm Tube with Hungate Cap, 10ml 20 tubes/box
Cat. no. U41 Fluid Thioglycollate, USP, 8oz. Wide Mouth Glass Jar, 100ml 12 jars/box
Cat. no. U43* Fluid Thioglycollate without Indicator, USP, 6oz. Glass Bottle, 100ml 20 bottles/box
Cat. no. U66 Fluid Thioglycollate, USP, 20ml Serum Vial, 15ml 50 vials/box
Cat. no. U68 Fluid Thioglycollate, USP, 20ml Serum Vial, 20ml 50 vials/box
Cat. no. U84 Fluid Thioglycollate, USP, 100ml Serum Vial, 100ml 20 vials/box
Cat. no. U121 Fluid Thioglycollate, USP, 4oz. Glass Bottle, 100ml 20 bottles/box
Cat. no. U207 Fluid Thioglycollate, USP, 200ml Serum Vial with Septum Cap, 150ml 10 vials/box
Cat. no. U273 Fluid Thioglycollate, USP, 500ml Glass Bottle with Septum Cap, 500ml 10 bottles/box
Cat. no. U427 Fluid Thioglycollate, USP, 500ml Glass Bottle with Septum Cap, 300ml 10 bottles/box
Cat. no. U434 Fluid Thioglycollate, USP, 8oz Boston Round Glass Bottle, 200ml 12 bottles/box
Cat. no. U449 Fluid Thioglycollate, USP, 20ml Serum Vial with Septum Cap, 10ml 50 vials/box

* Product does not contain resazurin indicator.

** ReadyRack is a plastic rack designed for cleanroom use and can be rinsed with alcohol.

INTENDED USE

Hardy Diagnostics Fluid Thioglycollate Media, USP is recommended for the cultivation of aerobic, microaerophilic, and anaerobic microorganisms in normally sterile materials. Fluid Thioglycollate Medium conforms to the formula stated in the United States Pharmacopeia (USP).(4)

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

SUMMARY

The Fluid Thioglycollate Medium formulation was first described in 1940 by Brewer.(1) This medium demonstrated that combining a small amount of agar and a reducing substance initiated the growth of anaerobic bacteria. The Fluid Thioglycollate formulation is the standard medium recommended by the Food and Drug Administration, National Institute of Health, the National Formulary, and the U.S. Pharmacopeia for sterility testing of clear fluid biologics and other sterile products.(2,4,5)

The addition of a small amount of agar in the media aids in the initiation and growth of small inocula and anaerobes by impeding the diffusion of oxygen into the medium. It also retards the dispersion of CO2 and the reducing substance from the microenvironment surrounding the inoculum. Sodium thioglycollate is a reducing agent which maintains a low oxygen tension by removing molecular oxygen from the environment. Peroxides, which may be lethal to many anaerobic organisms, are not formed under this condition. Cystine and casein supply carbon and nitrogenous compounds, dextrose is added as another energy source, and sodium chloride maintains osmotic equilibrium.

Certain additives can be incorporated into the Fluid Thioglycollate Medium as desired. Resazurin is an oxidation-reduction indicator that turns pink when increased oxidation has occurred. Yeast extract, papaic digest of soybean meal or beef extract are added as growth enhancers. Lecithin and Tween® 80 are added to neutralize germicidal or disinfectant residues; neutralization of these residues reduces their inhibitory effect. Quaternary ammonium compounds are neutralized by lecithin while phenolic disinfectants and hexachlorophene are neutralized by Tween® 80. Together, lecithin and Tween® 80 neutralize ethanol.

FORMULA

Ingredients per liter of deionized water:*

Pancreatic Digest of Casein 15.0gm
Dextrose 5.5gm
Yeast Extract 5.0gm
Sodium Chloride 2.5gm
Sodium Thioglycollate 0.5gm
L-Cystine 0.5gm
Agar 0.75gm

If added:
Resazurin indicator** 1.0mg

Final pH 7.1 +/- 0.2 at 25ºC.

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

** For those products that do not contain resazurin indicator, final pH is 7.2 +/- 0.2 at 25ºC.

Formulated in accordance with USP <71>.(8)

STORAGE AND SHELF LIFE

Storage: Upon receipt store at 2-25ºC 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 and freezing.

PRECAUTIONS

PROCEDURE

In some tubes, the media may become oxidized within the tube during shipment. Resazurin, an oxidation-reduction indicator causes the entire medium to turn pink when oxidation has occurred. These tubes may be restored to their proper condition by bringing the media up to 100ºC in a boiling waterbath. Loosen screw caps slightly before heating, and tighten during cooling to room temperature. The boiling serves to reduce media intended for the culture of anaerobic organisms.

Method of Use: Consult the U.S. Pharmacopeia for sterility testing procedures.(4)

Note: Fluid Thioglycollate contains a resazurin indicator which will cause the upper 1/3 layer of this broth to be pink, due to exposure to oxygen. Containers that have been agitated recently (as during shipping) will turn pink throughout. This can be reversed by allowing the container to stand still for a few hours or by putting the containers in a boiling waterbath for 10 minutes with loosened caps. The caps are then tightened firmly before the media cools. Also note that it is common for a whitish precipitate to form in this medium due to the agar content. This does not effect the performance of this medium.

INTERPRETATION OF RESULTS

Consult U.S. Pharmacopeia for interpretation guidelines for testing.(4)

LIMITATIONS

In test samples, the proper surface to volume ratio of the Fluid Thioglycollate Medium must be maintained to avoid oxidation of the medium, making it unsuitable for microaerophilic and anaerobic growth.(4)

A slight turbidity of haziness may be present due to the small amount of agar in the medium. When the media has been boiled it appears clear.

Do not boil the media more than once, as frequent boiling may lead to toxic products forming in the medium.(3) If it is suspected that the medium has more than 30% oxidation after boiling, it should be discarded.

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 indicators, serological and biochemical reagents, are not provided.

QUALITY CONTROL

Test Organisms Inoculation Method* Incubation Results
Time Temperature Atmosphere
Staphylococcus aureus
ATCC® 6538
J 24-72hrs 30-35°C Aerobic Growth
Pseudomonas aeruginosa
ATCC® 9027
J 24-72hrs 30-35°C Aerobic Growth
Clostridium sporogenes
ATCC® 19404
J 24-72hrs 30-35°C Aerobic** Growth

** Tubes, bottles and jars are incubated in an aerobic incubator with the caps screwed down tightly to create an atmosphere of low oxygen tension within the tube.

*** Tested in accordance with USP <61> and <62>.(6,7)

User Quality Control

Physical Appearance

Fluid Thioglycollate Medium should appear translucent, and light amber in color. Containers with oxygen present will have a pink layer at the medium-air interface. If the media appears pink in color, follow the instructions given in the above "Procedure" section to restore and reduce the media.

S. aureus growing in Fluid Thioglycollate Media, USP

Clostridium sporogenes (ATCC® 19404) growing in Fluid Thioglycollate Media, USP (Cat. no. K121). Incubated aerobically with tightened cap for 24 hours at 35ºC.

Fluid Thioglycollate Media, USP

Uninoculated tube of Fluid Thioglycollate Media, USP (Cat. no. K121).

REFERENCES

1. Brewer, J.H. 1940. J. Amer. Med. Assoc.; 115:598.

2. Federal Security Agency, Food and Drug Administration, Compilation of Regulations for Test and Methods of Assay and Certification of Antibiotic Drugs.

3. MacFaddin, J.F. Biochemical Tests for Identification of Medical Bacteria, Lipincott Williams & Wilkins, Philadelphia, PA.

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

5. National Institutes of Health Circular: Culture Media for the Sterility Test, 2nd rev. Feb. 5, 1946.

6. The Official Compendia of Standards. USP General Chapter <61> Microbiological Examination of Nonsterile Products: Microbial Enumeration Tests. USP-NF. United States Pharmacopeial Convention Inc., Rockville, MD.

7. The Official Compendia of Standards. USP General Chapter <62> Microbiological Examination of Nonsterile Products: Tests for Specified Microorganisms. USP-NF. United States Pharmacopeial Convention Inc., Rockville, MD.

8. The Official Compendia of Standards. USP General Chapter <71> Microbiological Examination of Nonsterile Products: Tests for Specified Microorganisms. USP-NF. United States Pharmacopeial Convention Inc., Rockville, MD.

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

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