Method for the enumeration of Pseudomonas spp.
ISO / TS 11059 (2009) method: Pseudomonas spp.
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1 Quantitative process control with CRM-PF
- Use a quantitative reference material (CRM-PF) with a known number of Pseudomonas fluorescens.
- Defrost the material at room temperature for 30 minutes.
- Mix well before use and dilute the material so countable numbers are inoculated on the media (PPA) by spread plate method.
- Best results are obtained when a practicable range of 80 cfu to 120 cfu per plate with a minimum number of 50 cfu per plate is used.
- Incubate at (25 ± 1) °C for (48 ± 2) h.
- Count the colony forming units and register in a control chart.
- The characteristic reaction is: Growth.
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2 Quantitative process control with RM-PA
- Use a quantitative reference material (RM-PA) with a known number of Pseudomonas aeruginosa.
- Defrost the material at room temperature for 30 minutes.
- Mix well before use and dilute the material so countable numbers are inoculated on the media (PPA) by spread plate method.
- Best results are obtained when a practicable range of 80 cfu to 120 cfu per plate with a minimum number of 50 cfu per plate is used.
- Incubate at (25 ± 1) °C for (48 ± 2) h.
- Count the colony forming units and register in a control chart.
- The characteristic reaction is: Growth.
Best Practice
The single strain CRM-PF is used for the enumeration of Pseudomonas spp.
Best Practice
The single strain RM-PA is used for the enumeration of Pseudomonas spp.