Dehydrated culture media
Mossel EE Broth EP/USP
For the selective enrichment of Enterobacteriaceae.
- Cat. No.
- LC-1202
- Category
- Dehydrated culture media
- Format
- 500 g
- Storage
- 2 to 25 °C
- Minimum guaranteed shelf life
- 15 months
- Standards
- European PharmacopoeiaUSP
- Also available
- Ready-to-use medium, 2 formats (LC-4043)
Mossel EE (Enterobacteriaceae Enrichment) Broth is an enrichment broth, used to promote the growth of the Enterobacteriaceae group, microorganisms which contaminate foods. The European Pharmacopoeia, USP in paragraph 2.6.13: "Microbiological examination of non-sterile products: test for specified microorganisms" recommends this medium for the testing of bile-tolerant Gram-negative bacteria in products.
Key features
Applications
Selective enrichment of enterobacteria.
Industry
Final product quality control, food, pharmaceutical/veterinary.
Standards
European Pharmacopoeia, USP.
Preparation
45 g in one liter of distilled water; boil for one minute, heat at 100 °C for 30 minutes, do not autoclave.
Principles and uses
The enumeration of Enterobacteriaceae is of great importance when controlling the sanitary condition of food. Microorganisms can be injured in food processing, including exposure to low temperatures, submarginal heat, drying, radiation, preservatives or sanitizers. Recovery depends on the adequate resuscitation of damaged cells. Escherichia coli, even though present in small numbers as a contaminant in foods, grows easily in this medium.
Pancreatic digest of gelatin provides nitrogen, vitamins, minerals and amino acids essential for growth. Glucose is the fermentable carbohydrate providing carbon and energy. Disodium phosphate and monopotassium phosphate act as a buffer system. Brilliant green and ox bile are selective agents, inhibiting Gram-positive microorganisms.
Technical specifications
| Solubility | Without residues |
|---|---|
| Appearance | Fine powder |
| Color of the dehydrated medium | Beige |
| Color of the prepared medium | Green |
| Final pH (25 °C) | 7.2 ± 0.2 |
| Amount per litre | 45 g |
| Storage | 2 to 25 °C |
Formula
| Ingredient | g/L |
|---|---|
| Brilliant green | 0.015 |
| Gelatin pancreatic digest | 10 |
| Glucose monohydrate | 5 |
| Potassium dihydrogen phosphate | 2 |
| Disodium hydrogen phosphate dihydrate | 8 |
| Dehydrated ox bile | 20 |
Typical formula in g/L, adjusted and/or supplemented as required to meet performance criteria.
Preparation and use
Preparation
Suspend 45 grams of the medium in one liter of distilled water. Mix well and dissolve by heating with frequent agitation. Boil for one minute until complete dissolution. Heat at 100 °C for 30 minutes. Cool immediately. AVOID OVERHEATING. DO NOT AUTOCLAVE. Dispense into appropriate containers.
Instructions for use
For the test of specified microorganisms (bile-tolerant Gram-negative bacteria) according to the European Pharmacopoeia:
- Prepare the sample using a 1 in 10 dilution of not less than 1 g of the product in Trypticasein Soy Broth (TSB) (LC-1224) and incubate at 20-25 °C for 2-5 hours.
- For the absence test, use the dilution made previously corresponding to 1 g of the product to inoculate in Mossel EE Broth and incubate at 30-35 °C for 24-48 hours.
- Subculture on plates of Violet Red Bile Agar with Glucose (VRBG) (LC-1092) and incubate at 30-35 °C for 18-24 hours. The product complies with the test if there is no growth of colonies.
- For the quantitative test, use the dilution made previously corresponding to 0.1, 0.01 and 0.001 g of the product to inoculate in Mossel EE Broth and incubate at 30-35 °C for 24-48 hours.
- Subculture on plates of Violet Red Bile Agar with Glucose (VRBG) (LC-1092) and incubate at 30-35 °C for 18-24 hours.
- Growth of colonies constitutes a positive result.
Quality control
According to European Pharmacopoeia
Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538 and Pseudomonas aeruginosa ATCC 9027.
Incubation conditions: 30-35 °C / 24-48 h.
Inoculation conditions: productivity (≤ 100 CFU) / inhibitory (≥ 100 CFU).
Rest of strains
Incubation conditions: 35 ± 2 °C / 18-48 h.
| Microorganism | Specification | Characteristic reaction |
|---|---|---|
| Escherichia coliATCC 8739 + Enterococcus faecalis ATCC 19433 | ≥ 10 colonies on VRBG | Pink to red colonies with or without precipitation halo |
| Enterococcus faecalisATCC 29212 | Total inhibition (0) | |
| Staphylococcus aureusATCC 6538 | Total inhibition (0) | |
| Escherichia coliATCC 8739 | Good growth, turbidity | |
| Pseudomonas aeruginosaATCC 9027 | Good growth, turbidity |
Bibliography
- Mossel D.A.A., Visser M. and Cornelissen A.M.R. J. App. Bact. 24:444. 1963.
- Mossel D.A.A. et al. J. Bact. 84:381. 1982.
- European Pharmacopoeia 9.0
What you receive
The product
Shipped under controlled temperature when the product requires it.
Lot certificate
Every lot comes with its certificate.
Tracked shipment
Follow your shipment live, from our warehouse to your lab.
Related products
Frequently asked questions
Can I ask for formats other than those listed?
Yes: custom formats and OEM packs are available on request. Tell us the quantities you need.
How do I see the prices?
Prices are shown after you sign in to the customer area, with your account discount already applied.
How long does delivery take?
We give you the availability with the quote, within 24 hours of your request.