Oxoid MAC-CONKEY AGAR NO 3 CM0115B

Oxoid Mac-Conkey Agar No. 3 CM0115B

Oxoid Mac-Conkey Agar No. 3 CM0115B is a selective and differential medium designed for the isolation and enumeration of coliform organisms and enteric bacteria, particularly from clinical, water, dairy, and food samples. It differentiates lactose fermenters (typically coliforms) from non-lactose fermenters through color changes, making it a widely used medium in microbiological diagnostics and food safety testing.

Features

• selective medium – contains bile salts and crystal violet to inhibit Gram-positive bacteria

• differential formulation – lactose and neutral red indicator differentiate lactose fermenters (pink/red colonies) from non-fermenters (colorless)

• high clarity – transparent medium for easy observation of colony morphology

• supports rapid results – clear differentiation within 18–24 hours

• broad application – suitable for a wide range of sample types including food, clinical, and water samples

• reliable performance – consistent and reproducible results across different laboratories

Application

• clinical diagnostics – used to isolate and identify enteric pathogens such as E. coli and Salmonella

• water analysis – detection of coliform bacteria in drinking and wastewater

• food safety – monitoring contamination in dairy, meat, and ready-to-eat foods

• dairy industry – assessment of coliform content in milk and dairy products

• pharmaceutical microbiology – used in quality control testing of non-sterile products

• education and research – a common tool for training in microbiology and research labs

Specification

• product name: Oxoid MacConkey Agar No. 3 CM0115B

• format: dehydrated culture medium

• typical composition per liter:

  • peptone: 20.0 g

  • lactose: 10.0 g

  • bile salts No. 3: 1.5 g

  • sodium chloride: 5.0 g

  • neutral red: 0.03 g

  • crystal violet: 0.001 g

  • agar: 12.0–15.0 g

• final pH: 7.1 ± 0.2 at 25 °C

• preparation: dissolve 50.5 g in 1 liter of distilled water, boil to dissolve completely, sterilize by autoclaving at 121 °C for 15 minutes

• storage conditions: store tightly closed in a dry place at 10 – 30 °C, protect from moisture and light

• shelf-life: use before expiry date indicated on the packaging

Conclusion

Oxoid MacConkey Agar No. 3 CM0115B is a fundamental medium in microbiology labs, offering reliable isolation and differentiation of coliforms and other enteric bacteria. With its selective and differential capabilities, it is ideal for routine testing and surveillance across clinical, environmental, and industrial applications.