Polysorbate 80 Agar (Twin Pack)

Polysorbate 80 Agar is used for the cultivation of variety of microorganisms.

Composition**

Ingredients

**Formula adjusted, standardized to suit performance parameters

Directions

Suspend 25 grams of Part A in 990 ml distilled water. Heat to boiling to dissolve the medium completely. Add 10 ml of Part B. Mix well and sterilize by autoclaving at 15 lbs pressure (121°C) for 15 minutes. Mix well and pour into sterile Petri plates.

Principle And Interpretation

Polysorbate 80 Agar is recommended for the cultivation of variety of microorganisms (1). It is a nutritional medium containing neutralizing agent. This medium thus helps in neutralizing phenolic disinfectants, hexachlorophene and formalin present in the medium thereby increasing the metabolic rate of the organisms.

The medium contains peptic digest of animal tissue, which provide the necessary nutrients for the growth of the organisms. Polysorbate 80 provides fatty acids for the metabolism of the organisms and neutralizes phenolic disinfectants, hexachlorophene and formalin (2).

Quality Control

Appearance

Part A: Cream to yellow homogeneous free flowing powder Part B: Colourless clear viscous liquid

Gelling

Firm, comparable with 1.5% Agar gel

Colour and Clarity of prepared medium

Yellow coloured clear gel forms in Petri plates

Reaction

Reaction of the medium (2.5% w/v part A + 1.0% w/v part B) at 25°C. pH: 7.2±0.2

pH

7.00-7.40

Cultural Response

M1307: Cultural characteristics observed after an incubation at 35-37°C for 18-24 hours.

Storage and Shelf Life

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

Reference

1. Atlas R. M., 1997, ln: Handbook of Microbiological Media, 2nd Edition, Lawrence C Parks (Ed.), CRC Press, London.
2. Favero M.S., (chm.) 1967, Microbiological sampling of surfaces, Biological Contamination Control Committee, American Asso. For Contamination Control.