Illuminating Pseudomonas: A Deep Dive into the ISO 16266:2006 Procedure for Precise Detection and Enumeration

Navigating the Rigorous Protocol for Pseudomonas aeruginosa to Safeguard Water Quality and Public Health
January 25, 2024 by
Desiree Okpiaifo


​Pseudomonas aeruginosa, a widely distributed bacterium in the environment, is commonly found in soils, natural water sources, lakes, and rivers. While its presence is infrequent in drinking water, its detection is crucial in specific settings, particularly healthcare facilities, where it can pose a risk of infection. Although regular consumption of drinking water is not a typical source of P. aeruginosa infection for the general population, control measures are essential to limit the formation of biofilms and reduce the proliferation of these microorganisms.

Detection Method: ISO 16266:2006

The sample is filtered according to the specifications outlined in ISO 8199.
Presumptive Isolation:
Place the membrane post-filtration in Pseudomonas CN Agar.
Incubate at 36 ºC ± 2 ºC for 44 ± 4 hours.
Examine growth after 22 hours and at the end of incubation.
Reading under Natural Light:
a) Blue/green colonies are counted as Pseudomonas aeruginosa.
b) Red/brown colonies are considered presumptive, and confirmatory tests are required.
After subculture in Nutrient Agar, perform the following tests:
Oxidase reaction (+)
Inoculate on Acetamide broth (+) 
Inoculate on King B Medium (+) 
Reading under UV Light:
Fluorescent colonies not producing pyocyanin are considered presumptive Pseudomonas aeruginosa.
Confirmation (UV Light):
After subculture in Nutrient Agar, perform inoculation on:
Acetamide broth (+) 

The ISO 16266:2006 procedure provides a comprehensive method for the detection and count of Pseudomonas aeruginosa. By following these meticulous steps, professionals can ensure accurate identification, enabling effective control measures to minimize the risk of infection in various environments. The integration of natural and UV light readings enhances the specificity of the detection process, contributing to the overall safety and quality of water systems.

Related Products:

Condalab 1153 - Pseudomonas CN Agar Base ISO 500grams (minimum order quantity of 4)

Condalab 1532 - King B Medium (Pseudomonas F Agar) ISO 500 grams (minimum order quantity of 5 units)

Condalab 1155 - Acetamide Broth Base ISO 500grams

Condalab 1156 - Nutrient Agar ISO 500grams (minimum order quantity of 6 units)

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