Page 74 - MNU PM502 Ph. Micreo practical

Pharm D- Clinical Pharmacy Program Third Level Pharmaceutical Microbiology& Antimicrobials (PM 502)

Surface-Spread Method

1. A measured volume of 0.1 mL of the diluted samples, prepared as in pour plate

method, were spread over the surface of the media using glass spreader.

2. Two petri dishes were used for each medium and each level of dilution.

3. The plates were incubated at 30–35 °C and five days for bacteria and 20–25 °C,

seven days for fungi.

4. Plates corresponding to a single dilution showing the highest number of colonies

less than 300 (100 for fungi) were selected for counting. The arithmetic average

of the counts was taken and the number of CFU per gm or ml was calculated.

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