Product Specifications
- Product Name: Pseudomonas Agar Medium for Pyocyanin Detection (PAP)
- Format: Powder Medium
- Net Weight: 250 g / bottle
- Storage: Store in a cool and dry place at room temperature
- Shelf Life: 3 years
- Application: Pyocyanin detection test for Pseudomonas aeruginosa
Composition (g/L)
(The formulation may vary depending on laboratory standards)
Peptone
Magnesium Chloride
Potassium Sulfate
Agar
Principle of the Test
Pseudomonas aeruginosa produces pyocyanin pigment, which can be extracted with chloroform. The pigment has higher solubility in water than in chloroform and undergoes reversible oxidation-reduction reactions.
In alkaline conditions, the pigment appears blue, while in acidic conditions it appears red. When hydrochloric acid is added after extraction, pyocyanin transfers from the chloroform layer to the acidic aqueous layer, producing a pink to red color, which indicates a positive result.
Test Procedure
- Pick a suspected colony and inoculate onto the Pseudomonas Agar Medium slant.
- Incubate for 24 hours.
- Observe pigment production on the slant surface.
- If pigment appears, add 3–5 mL chloroform to the tube.
- Shake thoroughly to extract the pigment into the chloroform layer.
- When the chloroform extract becomes green, add approximately 1 mL of 1 mol/L hydrochloric acid.
- Shake and allow to stand briefly.
Result Interpretation
- Upper hydrochloric acid layer turns pink to red → Positive
- No color change → Negative
Preparation Instructions
- Weigh 46.4 g of the medium powder.
- Add 10 g glycerol.
- Dissolve in 1000 mL distilled water.
- Dispense into suitable containers.
- Sterilize at 121°C for 15 minutes.
- Cool and use as required.
Note:
The medium contains a small amount of magnesium chloride, and slight precipitation may appear after sterilization.