E. coli · QC reference strain
E. coli QC Strain – reference strain for media testing
Escherichia coli CMCC(B) 44102 is a qualitative reference strain for growth-promotion testing of culture media, positive controls and method verification in food, water and pharmaceutical microbiology.
- Lyophilised, single use
- For growth-promotion and positive controls
- Rehydration fluid included
How E. coli QC Strain is used
The lyophilised culture is rehydrated with the supplied fluid, spread on a non-selective plate and subcultured before use. Working cultures are kept within five passages from the reference strain.
Technical data
| Preparation | Add 1.0 mL supplied recovery fluid, vortex; spread 0.1 mL on non-selective plate or into broth |
| Incubation | Most bacteria 36 ± 1 °C 24-48 h; moulds/yeasts 26 ± 1 °C 2-5 d; Campylobacter 42 °C microaerophilic; clostridia anaerobic 48-96 h |
| Storage | Per label; opened/unused and reconstituted at 2-8 °C, use reconstituted within 8 h |
Applications and practical notes
Reference strains of E. coli are used for growth-promotion and selectivity testing of culture media according to ISO 11133 and for positive controls in routine methods. Typical applications include:
- Growth-promotion testing of new media lots
- Positive controls for coliform and E. coli methods
- Proficiency and method-verification studies
- Pharmacopoeial microbial limit tests
Working with E. coli QC Strain: Subculture two to three times before use, and do not use more than five passages from the original vial.
Good practice with rapid tests: store the kit as stated on the label, let the components reach room temperature before use and use each item only once. Record the lot number and the result, and confirm positive results according to the reference method when this is required.
About coliform and E. coli methods: coliforms and E. coli are counted either by the multiple-tube (MPN) method, with a presumptive broth followed by confirmation broths, or by colony counts on selective agars. FDA BAM Chapter 4 describes both approaches for food and water, and ISO 16649-2 gives the colony-count method for β-glucuronidase-positive E. coli on TBX Agar. E. coli O157 and other STEC need dedicated media, serology and PCR. COLO.Science offers media, supplements, rapid tests, identification kits and QC strains for every step.
Complete sets from one supplier: COLO.Science supplies culture media, supplements, rapid tests, identification kits and QC strains as complete sets for the method you follow. Send us your sample types and standards, and we will prepare an offer with the matching products and documentation.
E. coli QC Strain is supplied by COLO.Science in the pack sizes listed under Ordering information. For larger quantities, regular deliveries or method-specific sets that include E. coli QC Strain, please send us a request. With every delivery of E. coli QC Strain you receive the lot number and expiry date, and on request we send the available documentation for E. coli QC Strain.
Where E. coli QC Strain fits in coliform and E. coli testing
- Presumptive test – Lauryl Sulfate Tryptose Broth (MPN) or VRBL / chromogenic agar (colony count)
- Confirmation – BGLB Broth for coliforms; EC or EC-MUG Broth at 44.5 °C for E. coli
- Isolation – EMB, MacConkey, TBX or chromogenic E. coli agar
- Identification – IMViC kit; for O157 and STEC: SMAC or chromogenic O157 agar, latex and PCR
Ordering information
| Product | COLO code | Pack |
|---|---|---|
| E. coli QC Strain CMCC(B) 44102 | PRO7841 | 1 vial |
Product notice: preparation, storage conditions and shelf life are given on the label. Technical data on this page are for orientation; the label and the lot documentation apply. B2B prices are quoted net, excluding VAT.
Sales and technical support
COLO LabExperts
Polje ob Sotli 4, SI-3255, Slovenia
Quotations and technical support for culture media and microbiology products across our international sales territory. B2B prices are net, excluding VAT.
COLO.SCIENCE | MICROBIOLOGY SUPPORT
Need the complete set for your method?
Send the sample type, target organism and the standard you follow. COLO.Science will put together the media, supplements, QC strains and confirmation tests for the whole procedure.
