Pseudomonas Oxidase test: Principle, Procedure, Reagents

Oxidase test helps to identify the vibro, Neisseria and Pseudomonas.

Principle of oxidase test

Pseudomonas Aurogenosa produced Oxidase Enzyme, which oxidizes the Phenylene Diamine to purple-colored compound.

Reagent for Oxidase test

Oxidase reagent is freshly prepared. It is a 1% solution of Tetramethyl-p-Phenylene Diamine Dihydrochloride.

Oxidase Test Procedure

Following steps are performed for oxidase test procedure.

1. Place a clean filter paper in a clean petri dish.
2. Add 3 to 4 drops of freshly prepared Oxidsae reagent on the filter paper.
3. Pick the colony of the test organism with the help of a gloss rod and smear it on that filter paper.
4. Examine the color of the colony on filter paper.

If blue purple color identified, the result will be oxidase positive.

What is the positive color of oxidase test?

Blue purple color on the filter paper after smearing colony is the positive color of oxidase test.

Why is the oxidase test important?

Oxidase test is important in the biochemical identification of bacteria. With the help of oxidase, we easily identify the colony of Pseudomonas and bacteria.

List of Oxidase Positive Bacteria

Pseudomonas oxidize the oxidase reagent (Tetramethyl-p-Phenylene Diamine Dihydrochloride), therefore it is oxidase-positive bacteria.

List of Oxidase Negative Bacteria

Eschrechia Coli is oxidase negative bacteria.