Liofilchem® LISTERIA OXFORD Supplement w CEF-FOS-COL-CYC-ACR, 10 Vials

​The LISTERIA OXFORD Supplement w CEF-FOS-COL-CYC-ACR from Liofilchem® is a highly selective antimicrobial supplement specifically designed for the isolation of Listeria monocytogenes from food and environmental specimens when used in combination with Listeria Oxford Agar Base (codes 610231 or 620231).

This supplement is supplied as a freeze-dried (lyophilized) formulation containing a carefully balanced combination of five selective agents that work synergistically to suppress competing bacterial and fungal flora while allowing optimal growth and recovery of Listeria monocytogenes.

Principle of the Method

The selectivity of Listeria Oxford Supplement w CEF-FOS-COL-CYC-ACR is achieved through the combined antimicrobial action of its components:

• Cycloheximide – inhibits the growth of saprophytic fungi
• Acriflavine – suppresses competing Gram-positive bacteria
• Phosphomycin – inhibits a wide range of contaminating bacteria
• Cefotetan – enhances selectivity against non-Listeria organisms
• Colistin sulphate – provides bactericidal activity against Gram-negative bacteria

When added to Listeria Oxford Agar Base, the supplement creates a selective medium that promotes the growth of Listeria monocytogenes while inhibiting background flora commonly present in food and environmental samples.

Composition

Per Vial / Per Litre of Medium

Kit Contents

Each kit contains:

• 10 freeze-dried vials of LISTERIA OXFORD Supplement w CEF-FOS-COL-CYC-ACR
• 1 instruction sheet

One vial is sufficient to prepare 500 mL of selective medium.

Procedure for Use

1. Aseptically reconstitute the contents of one vial with 5 mL of a 1:1 mixture of sterile distilled water and ethanol.
   • Shake gently until fully dissolved
   • Avoid foam formation
2. Aseptically add the entire 5 mL solution to 500 mL of Listeria Oxford Agar Base (code 610231 or 620231) that has been:
   • Autoclaved
   • Cooled to 45–50 °C
3. Mix carefully and pour into sterile Petri dishes.

Performance & Interpretation

Interpretation of results should be carried out in accordance with the technical documentation for Listeria Oxford Agar Base. Typical Listeria colonies appear as grey-green colonies with black halos due to esculin hydrolysis.

Quality Control

Appearance

• Freeze-dried, yellow in colour

Microbiological Performance

Applications

• Detection of Listeria monocytogenes in food products
• Environmental monitoring in food processing facilities
• Dairy, meat, and ready-to-eat food testing
• Public health and regulatory microbiology
• Quality control laboratories

Storage & Stability

• Storage Temperature: 2–8 °C
• Store in original packaging, protected from heat and temperature fluctuations
• Shelf life: Until expiry date on label
• Once reconstituted, the supplement may be stored for up to 30 days at –20 °C, protected from light

Safety & Precautions

• Contains substances classified as dangerous under EU Directives 1999/45/CE and 2001/60/CE
• Intended for professional laboratory use only
• Must be handled by trained personnel using appropriate biosafety and aseptic techniques

Standards & References

• TIL-IDF (1988): Detection of Listeria monocytogenes in milk and milk products
• ISO 10560: Milk and milk products – Detection of Listeria monocytogenes

Packaging & Ordering Information

Liofilchem® LISTERIA OXFORD Supplement w CEF-FOS-COL-CYC-ACR provides a robust, highly selective, and well-validated solution for the isolation of Listeria monocytogenes from complex food and environmental samples. Its multi-agent formulation ensures excellent inhibition of competing flora, consistent performance, and compliance with recognized international microbiological standards, making it an essential component of food safety and public health testing workflows.