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Catalase test

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    Catalase  test– this test determines bacterial production of catalase enzymes.

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1.      Place a drop of hydrogen peroxide (3% H2O2 - reagent grade) on a microscope slide or in the concave surface of a hanging drop slide.

2.      With a sterile loop, collect a sample of 18-24 hour old pure bacterial culture.

 3.      Place the loop in the hydrogen peroxide.

 4.      If the test is positive, there will be immediate bubbling or foaming, and liberation of O2 gas.


5.      Record results.
Positive : If the mixture produces bubbles or froth, the organism is said to be 'catalase-positive

( Staphylococcus and Micrococcusare catalase-positive. Other catalase-positive organisms 

include Listeria, Corynebacterium diphtheriae, Burkholderia cepacia, Nocardia, the family 

Enterobacteriaceae 

(Citrobacter, E.coli, Enterobacter, Klebsiella, Shigella, Yersinia, Proteus, Salmonella, Serratia), Pseudom

onas, Mycobacterium tuberculosis, Aspergillus, Cryptococcus, and Rhodococcus equi).

Negative:If it is not produces bubbles, the organism is 'catalase-negative ( Streptococcus and Enterococcus spp. are catalase-negative ).

    QUALITY CONTROL:
Positive : Staphylococcus sp
Negative: Streptococcus sp 
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