Protocol for catalase and Oxidase test for bacterial cells
1.
Catalase
Test:
Procedure:
1. Transfer a small amount of bacterial colony to
a surface of clean, dry glass slide using a loop or sterile wooden stick
2.
Place a drop of 3% H2O2 on to the
slide and mix.
3. A positive result is the rapid evolution of
oxygen (within 5-10 sec.) as evidenced by bubbling.
4. A negative result is no bubbles or only a few
scattered bubbles.
5. Dispose of your slide in the biohazard glass
disposal container.
Reagent:
1.
3% H2O2
-Take 1 ml
30-35% H2O2 and add 9 ml D/w.
 |
| Catalse test |
2. Oxidase Test:
Procedure:
(Wet Filter Method)
1.
A strip of filter paper
is soaked with a little freshly made 1% solution of tertramethyl-p-phenylene-diamine dihydrochloride reagent.
2.
A speck of culture is
rubbed on it with a platinum loop.
3.
A positive reaction is
indicated by an intense deep-purple hue, appearing within 5-10 seconds, a
“delayed positive” reaction by colouration in 10-60 seconds, and a negative
reaction by absence of colouration or by colouration later than 60 seconds.
 |
| Oxidase test |
Procedure:
(Dry Filter Method)
1.
Strip of Whatman’s No. 1
filter paper are soaked in a freshly prepared 1% solution of
tertramethyl-p-phenylene-diamine dihydrochloride.
2.
After draining for about
30 seconds, the strips are freeze dried and stored in a dark bottle tightly
sealed with a screw cap.
3.
For use, a strip is
removed, laid in a petri dish and moistened with distilled water.
4.
The colony to be tested
is picked up with a platinum loop and smeared over the moist area.
5.
A positive reaction is
indicated by an intense deep-purple hue, appearing within 5-10 seconds, a
“delayed positive” reaction by colouration in 10-60 seconds, and a negative
reaction by absence of colouration or by colouration later than 60 seconds.
Reagents: 1%
tetramethyl-p-phenylene-diamine dihydrochloride
-1 g
tetramethyl-p-phenylene-diamine dihydrochloride and add 100 ml d/w
