Bacillus subtilis · Quantitative QC strain
Bacillus subtilis Quantitative QC Strain – 10–100 CFU per inoculum
The Bacillus subtilis Quantitative QC Strain contains a defined number of cells (110–1100 CFU per vial). After rehydration, 0.1 mL gives 10–100 CFU, the inoculum required for pharmacopoeial growth promotion tests.
- Defined count: 110–1100 CFU per vial
- 10–100 CFU per 0.1 mL after rehydration
- For growth promotion tests
How Bacillus subtilis Quantitative QC is used
Add 1.1 mL of the supplied rehydration fluid, shake for 5 seconds and inoculate 0.1 mL directly onto the plate or into the broth. No dilution series is needed.
Technical data
| Preparation | Add 1.1 mL rehydration fluid, shake 5 s; 0.1 mL contains 10–100 CFU |
| Storage | −18 °C or below; rehydrated suspension 2–8 °C, use within 8 h |
| Shelf life | 18–24 months |
Applications and practical notes
Reference strains are used for media quality control according to ISO 11133 and for pharmacopoeial growth promotion tests. Typical applications include:
- Growth promotion and selectivity tests of media
- Positive and negative controls for biochemical tests
- Pharmacopoeial microbiological tests
- Method verification and proficiency testing
Working with Bacillus subtilis Quantitative QC: Store unopened vials at −18 °C or below and use the rehydrated suspension within 8 hours.
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 media quality control: ISO 11133 requires that each batch of culture medium is tested for productivity, selectivity and specificity with defined reference strains, and the pharmacopoeias require a growth promotion test with fewer than 100 CFU. General reference strains such as Bacillus subtilis, Proteus, Enterobacter, Serratia and Micrococcus serve as positive or negative controls on many media and in biochemical tests. COLO.Science supplies qualitative and quantitative reference strains together with the media.
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.
Bacillus subtilis Quantitative QC is supplied by COLO.Science in the pack sizes listed under Ordering information. For larger quantities, regular deliveries or method-specific sets that include Bacillus subtilis Quantitative QC, please send us a request. With every delivery of Bacillus subtilis Quantitative QC you receive the lot number and expiry date, and on request we send the available documentation for Bacillus subtilis Quantitative QC.
Where Bacillus subtilis Quantitative QC fits in media quality control
- Growth promotion – productivity of each new lot of medium
- Selectivity – inhibition of non-target organisms on selective media
- Biochemical controls – positive and negative controls for confirmation tests and ID kits
- Quantitative tests – defined-count strains for growth promotion with 10–100 CFU
See all QC reference strains in the Microbiology Catalogue →
Ordering information
| Product | COLO code | Pack |
|---|---|---|
| Bacillus subtilis Quantitative QC Strain 10^3 (CMCC 63501) | PRO7865 | 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.




