Charcoal Yeast Extract Agar (Legionella CYE Agar Base)

Application:

Charcoal Yeast Extract Agar (CYE) is used for the preparation of Buffered Charcoal Yeast Extract (BCYE) Agar, which is a selective medium for the isolation of Legionella species.

Product Specifications:

• Form: Dehydrated culture medium

• Packing Size: 250 g/bottle

• Storage: Room temperature

• Shelf Life: 3 years

Formula (per liter):

• Activated Charcoal ……………………………. 2.0 g

• Yeast Extract …………………………………….. 10.0 g

• Agar …………………………………………………. 15.0 g

Instructions for Use:

1. Dissolve 27.0 g of the medium in 900 ml of distilled or deionized water.

2. Heat to boiling until completely dissolved.

3. Sterilize by autoclaving at 121 °C for 15 minutes. Shake gently after sterilization.

4. Cool to about 50 °C and keep warm.

5. Under aseptic conditions, add supplements (such as ACES buffer, α-ketoglutarate, soluble ferric pyrophosphate, and L-cysteine hydrochloride) to adjust the final volume to 1000 ml.

6. Adjust the pH to 6.9 ± 0.2 (25 °C) if necessary.

7. Pour into sterile Petri dishes, allow to solidify, and store for use.

Colony Characteristics on BCYE Agar (prepared with CYE base):

• Legionella colonies: Typically gray-white to blue-gray, with a ground-glass appearance.

• Growth of many non-Legionella bacteria is inhibited due to the selective agents in the BCYE formulation.