Page 43 - MNU PM502 Ph. Micreo practical
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Pharm D- Clinical Pharmacy Program Third Level Pharmaceutical Microbiology& Antimicrobials (PM 502)
Chick – Martin test
Conditions of the test
1- The concentration of the test disinfectant and standard phenol is changed, but
the extinction time is fixed.
2- Used microorganism: Salmonella typhi, Staphylococcus aureus
3- This test evaluates the activity of the disinfectant in presence of organic matter.
The original test used 3% of sterilized human feces as organic matter, sterile yeast
extract is used instead of feces.
4- Time for subculture is fixed at 30 minutes
Pc: Lowest concentration of phenol showing no microbial growth (complete killing
of microorganism population).
Tc: Lowest concentration of test disinfectant showing no microbial growth
(complete killing of microorganism population).
C. M. coefficient = Lowest conc of phenol that kill M.O (Pc) / Lowest conc of test
disinfectant that kill M.O (Tc).
Practical mission:
You are provided with two flasks, one containing 5% phenol (Standard
Disinfectant) and the other one containing 100 ml of 2% of test disinfectant &
required to evaluate the test disinfectant according to Chick - Martin method.
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