Easy DryTM are absorbent pads saturated with a sterile, dehydrated culture medium. Each pad is pre-plated in a Petri dish and is immediately ready to use after pouring sterile distilled or deionized water on it. Easy DryTM are optimal for the examination of large sample volumes by the membrane filter method.
Easy DryTM Pseudomonas CN is a selective isolation medium used for the detection and enumeration of Pseudomonas aeruginosa in water, based on the promotion of pigment production, following the procedure given by EN ISO 16266.
PREPARATION
1.
Cut open a bag and remove the number of Easy Dry plates needed.
2.
Moisten the pad contained
in the Petri dish with 2.2 ml of sterile distilled or deionized water.
3.
Wait 5 minutes before
using.
TEST PROCEDURE
Filter the sample through a filter membrane
(0.45 µm pore diameter). Transfer
the membrane onto a plate containing a just
rehydrated pad. Incubate aerobically at 36 ± 2°C for 40-48 hours.
INTERPRETING RESULTS
Examine the membrane for growth and fluorescence under UV light at 360 nm after 20-24 h and 40-48 h.
• Count all colonies producing the green-blue pigment as confirmed Pseudomonas aeruginosa.
• Non-pyocyanin producing colonies that fluoresce under UV should be confirmed by the acetamide test.
• All other reddish-brown non-pigmented colonies that do not fluoresce should be submitted to further testing such as ammonia production from acetamide, oxidase production and fluorescence on King’s B medium.
For confirmation, select as many colonies as possible (all colonies if possible). Streak each colony onto a Nutrient Agar (NA) plate and incubate at 36 ± 2°C for 22 ± 2 h. Select one well isolated colony from each NA plate for the confirmatory tests.
APPEARANCE OF THE MEDIUM
Whitish pad. Yellowish once rehydrated.
STORAGE
Store at 10-25°C away from light. Do not
use the product beyond its expiry date on the label or if product shows any
evidence of contamination or any sign of deterioration.
SHELF LIFE
2 years.
