Tryptose Cycloserine Dextrose Agar Base

Tryptose Cycloserine Dextrose Agar Base

Tryptose Cycloserine Dextrose agar Base is recommended for the isolation of mesophilic spore forming anaerobes in food spoilage.

Composition**

Final pH (at 25°C): 7.6±0.2

**Formula adjusted, standardized to suit performance parameters

Directions

Suspend 23.0 grams in 500 ml. distilled water. If desired, add 0.5 to 1.0% dextrose. Heat to boiling to dissolve the medium completely. Sterilize by autoclaving at 15 lbs pressure (121°C) for 10 minutes. Cool to 50°C and aseptically add one vial of T.S.C. Supplement (FD014). Mix well and pour into sterile Petri plates.

Principle And Interpretation

Tryptose Cycloserine Dextrose Agar Base is used for isolation of mesophilic spore forming anaerobes in food spoilage (1). Tryptose cycloserine dextrose agar base has been effectively used as selective media for the isolation and enumeration of mesophilic anaerobic spore formers from environmental samples collected from cannery plant surveys (2).

Tryptose, papaic digest of soyabean meal, yeast extract provide nitrogenous compounds, carbon, vitamin B complex and trace elements essential for Clostridium growth. Incorporation of D-cycloserine in this medium effectiveley inhibits growth of most Enterococci.

Quality Control

Appearance Light yellow to light brown homogeneous free flowing powder

Gelling Firm, comparable with 2.0% Agar gel.

Colour and Clarity of prepared medium Light amber coloured clear to slightly opalescent gel forms in Petri plates.

Reaction Reaction of 4.6% w/v aqueous solution at 25°C. pH: 7.6±0.2

pH 7.40-7.80

Cultural Response

M1233: Cultural characteristics observed after an incubation at 35-37°C for 18-48 hours with added T.S.C. Supplement (FD014).

Storage and Shelf Life

Store below 30°C in tightly closed container and the prepared medium at 2-8°C. Use before expiry date on the label.

Reference

1. Downes F. P. and Ito K., (Eds.), 2001, Compendium of Methods for the Microbiological Examination of Foods, 4th Ed., APHA, Washington, D.C.
2. Lake D. E., Leseniewski R. S., Anderson J. E., Graves R. R. and Bremser J. F., 1985, J. Food Prot. 48: 794.