* Some products require configurations and options that can affect pricing.
Yeast Glucose Chloramphenicol Agar
(YGC) is a medium used for the selective isolation and enumeration of fungi.
METHOD PRINCIPLE
Yeast extract provide basic nutrients and is a good source of vitamins,
particularly of B-group. Glucose is the fermentable carbohydrate.
Chloramphenicol is the selective agent which inhibit the accompanying bacterial
flora resulting in better recovery of injured fungal cells. Agar is the
solidifying agent.
PREPARATION
Dehydrated medium: Suspend 43.1 g of the powder in 1 liter of
distilled or deionized water. Mix well. Heat to boil shaking frequently until
completely dissolved. Sterilize in autoclave at
121°C for 15 minutes.
Medium in bottles: Melt the content of the bottle in a water
bath at 100°C (loosing the cap partially removed) until completely dissolved.
Then screw the cap and check the homogeneity of the dissolved medium, if it is
the case turning the bottle upside down. Cool at 45-50°C, mix well avoiding
foam formation and aseptically distribute into Petri dishes
TEST PROCEDURE
Prepare sample dilutions in 1/4-strength Ringer’s Solution (ref. 81059)
or other suitable diluent. Inoculate the medium by pour plating or spread
plating method.
Large volumes of sample may be concentrated by membrane filtration.
Filters are then placed on YGC agar plates of 90 mm diameter.
Incubate plates aerobically at 25 ± 2°C for up to 5 days.
INTERPRETING RESULTS
Count colonies on all plates containing 15-300 colonies. Distinguish
yeasts from molds by colony morphology. Report the count as yeasts and moulds
per gram or per milliliter of sample allowing for dilution factors.
APPEARANCE
Dehydrated medium: free-flowing, homogeneous, light beige.
Prepared medium: slightly opalescent, light amber.
STORAGE
The powder is very hygroscopic, store the powder at 10-30°C, in a dry
environment, in its original container tightly closed. Store bottles, tubes and
prepared plates 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
