Liofilchem® Listeria Oxford Supplement, 10 Vials

​The Listeria Oxford Supplement from Liofilchem® is a selective antimicrobial supplement specifically formulated to support the selective isolation of Listeria monocytogenes when used in combination with Listeria Oxford Agar. It enhances the selectivity of the medium by inhibiting competing background flora while allowing the growth and differentiation of Listeria species.

This supplement is widely used in food microbiology, environmental monitoring, and public health laboratories, particularly for the detection of Listeria monocytogenes in food products, raw materials, and processing environments.

Principle of Use

Listeria Oxford Supplement contains selective antibiotics that suppress the growth of Gram-negative bacteria and many competing Gram-positive organisms, thereby improving the recovery of Listeria monocytogenes on Oxford selective agar.

When incorporated into Listeria Oxford Agar, the supplement enables the formation of typical Listeria colonies, which appear as small grey colonies with black halos due to esculin hydrolysis and ferric ion reaction, facilitating presumptive identification.

Composition (per vial)

• Cefotetan: 1 mg
• Phosphomycin: 5 mg

These antibiotics act synergistically to enhance selectivity without compromising Listeria recovery.

Instructions for Use

1. Aseptically reconstitute the contents of one vial with 5 mL of sterile distilled water.
2. Mix until the supplement is completely dissolved.
3. Aseptically add the reconstituted supplement to 500 mL of Listeria Oxford Agar (Code 610167 or 620167), previously autoclaved and cooled to 50 °C.
4. Mix thoroughly to ensure uniform distribution.
5. Pour into sterile Petri dishes and allow to solidify.

Key Features

• Selective supplement for Listeria monocytogenes isolation
• Optimized for use with Listeria Oxford Agar
• Contains cefotetan and phosphomycin for effective suppression of competing flora
• Lyophilized format for stability and ease of handling
• Consistent performance for routine and regulatory testing
• Suitable for food, environmental, and public health microbiology

Applications

• Detection of Listeria monocytogenes in food samples
• Environmental monitoring in food processing facilities
• Public health and regulatory microbiology
• Quality control in food and dairy industries
• Research and reference laboratories

Storage & Stability

• Storage Temperature: 5–12 °C
• Shelf Life: 3 years
• Store in original packaging, protected from light and moisture.

Packaging & Ordering Information

Standards & References

• Compendium of Methods for the Microbiological Examination of Foods (APHA)
• Curtis et al., Applied Microbiology, 1989
• Donnelly et al., Listeria, 1992

The Liofilchem® Listeria Oxford Supplement is a reliable, well-validated selective supplement essential for the accurate isolation of Listeria monocytogenes. When used with Listeria Oxford Agar, it delivers high selectivity, reproducibility, and compliance with standard microbiological methods, making it an indispensable tool for food safety and public health laboratories.