Tryptone Agar

Trptone Agar is used as a general purpose medium for growth of non-fastidious microorganisms.

Composition

**Formula adjusted, standardized to suit performance parameters

Directions

Suspend 33.0 grams in 1000 ml distilled water. Heat to boiling to dissolve the medium completely. Sterilize by autoclaving at 15 lbs pressure (121°C) for 15 minutes. Mix well and pour into sterile Petri plates.

Principle And Interpretation

Tryptone Agar is a general purpose nutritious medium for growth of non-fastidious microorganisms. Tryptone Agar was developed by Vera (1) for the accurate differentiation and identification of aerobes and anaerobes by means of motility and fermentation reactions. It is recommended for Clostridia, Bacillus species, Micrococci, enteric bacilli and other non-fastidious organisms (2). This is also an excellent medium for the maintenance for both aerobic and anaerobic cultures. Viability in this medium is greater than in any other broth medium or slant culture.

Casein enzymic hydrolysate provides essential growth nutrients to support the growth of organisms. Sodium chloride buffers the medium.

Quality Control

Appearance
Cream to yellow homogeneous free flowing powder

Gelling
Firm, comparable with 1.5% Agar gel

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

Cultural Response

M1365: Cultural characteristics observed after an incubation at 35-37°C for 24-48 hours.

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.

References

1. Vera, 1944, J. Bacteriol., 47:455.
2. MacFaddin J. F., 1985, Media for Isolation-Cultivation-Identification-Maintenance of Medical Bacteria, Vol. I, Williams and Wilkins, Baltimore.