This test is used to differentiate catalase-producing bacteria such, as Staphylococci from non-catalase-producing bacteria such as Streptococci.

    v   Principle:-

          Catalase produced by the organisms acts on hydrogen peroxide to produce water and oxygen (It is                     indicated by bubbles).

    v  Requirements:-

          1.      3% (v/v) Hydrogen peroxide

             2.       Test tubes (15 x 125 mm)

    v Procedure:-

1.       Pour 2 to 3 ml of hydrogen peroxide solution into a test tube.

2.       Immerse the growth of organisms in the test tube solution by using a
sterile wooden stick (or a sterile glass rod).

3.       Look for immediate bubbling.

    v   Observations:-

          1.      Appearance of bubbles: Presence of catalase-producing organisms.

             2.      No formation of bubbles: Presence of non-catalase-producing organisms.

    v   Precautions:-

          1.      The culture should not be for more than 24 hours.

             2.      This test should be performed from a blood-free culture medium (nutrient agar) since catalase is                      also  present in red blood cells

             v Quality control:-

Use the following
microorganisms to confirm the reliability of reagents:

1.      Positive control: Staphylococcus species

2.      Negative control: Streptococcus species