EC Broth
Also known as：EC · EC Medium · E. coli Broth · Escherichia coli Broth
For the detection of fecal coliforms and Escherichia coli in water, food, and shellfish by the multiple-tube fermentation technique at elevated temperature.
- Category
- Dehydrated Culture Media
- Dissolve per litre
- 37 g
- Pack sizes
- 500 g · 5 kg · 25 kg
- Certifications
- Halal
Data updated：2026-11-06
Brand cross-reference：BD Difco EC Medium · Oxoid EC Broth · Merck EC Broth（ISO 7251、FDA BAM） Brand cross-reference
Overview
EC Broth is the standard confirmation broth for coliforms and E. coli: bile salts suppress Gram-positive organisms and lactose lets coliforms produce gas. Incubation at 35 °C detects coliforms, while 44.5 °C detects thermotolerant (faecal) coliforms and E. coli, making it the usual confirmation step in MPN methods for food and water. With MUG added, E. coli can be confirmed rapidly by fluorescence.
Principle
EC Broth was developed by Hajna and Perry for the differentiation of fecal coliforms from coliforms of non-fecal origin.¹ Tryptose supplies nitrogen, amino acids, and growth factors, and lactose serves as the fermentable carbohydrate. Bile salts inhibit Gram-positive bacteria, including spore-formers, while the phosphate buffer maintains the pH and sodium chloride the osmotic equilibrium. Tubes inoculated from positive presumptive cultures are incubated at 44.5°C, a temperature at which thermotolerant (fecal) coliforms, principally Escherichia coli, ferment lactose with the production of gas, whereas most coliforms of non-fecal origin do not. Gas production in the Durham tube constitutes a positive result, and fecal coliform densities are calculated using most probable number tables.²
How selective media fit into the testing workflow
Pathogen testing normally runs in three stages: a pre-enrichment medium such as Buffered Peptone Water repairs injured cells and raises numbers, a selective enrichment then suppresses competing flora, and finally a selective differential agar isolates the target colonies. Selective agents are typically bile salts, dyes, or antibiotics; differential agents make target colonies develop a characteristic colour or morphology. Choose the combination specified by the method you follow.
Directions
Suspend 37 g of powder in 1 L of purified water. Heat with continuous stirring and bring to the boil for 1 minute. Dispense into tubes containing inverted Durham tubes. Sterilize by autoclaving at 121°C for 15 minutes. Test the finished medium for performance using stable, standard control cultures.
Cultural response
| Test organism | ATCC | Growth |
|---|---|---|
| Escherichia coli | 25922 | good-luxuriant |
| Klebsiella aerogenes | 13048 | poor to none |
| Enterococcus faecalis | 29212 | inhibited |
Product highlights
- Halal certified, suitable for the Malaysian, Indonesian, and Middle Eastern markets
- Manufactured to the standard formulation, 37 g per litre
- Performance verified against standard control strains before release (Escherichia coli, Klebsiella aerogenes, Enterococcus faecalis)
- Available in 500 g / 5 kg / 25 kg, from laboratory to industrial scale
- COA, specification sheet, and technical data sheet available; samples on request
- Manufactured in Taiwan with reliable supply
FDA BAM methods
This product corresponds to a medium used in the chapters of the US FDA Bacteriological Analytical Manual (BAM), the reference methods for FDA regulatory testing. Follow the current online edition of each chapter.
- FDA BAM Chapter 4: Enumeration of Escherichia coli and the Coliform BacteriaBAM Chapter 4Confirmation / biochemicalNamed in the method as：EC broth (45.5 °C)
BAM specifies methods and media formulations; it does not certify brands. Add supplements as the chapter requires, and verify media against reference strains under your quality system.
Frequently asked questions
01Does this medium meet FDA BAM methods?
BAM specifies methods and formulations, not brands. This product corresponds to a medium used in: FDA BAM Chapter 4: Enumeration of Escherichia coli and the Coliform Bacteria（BAM Chapter 4）: Confirmation / biochemical. It is manufactured to the standard formulation and ships with a COA per batch; add supplements as the chapter requires and follow the current online edition.
02Can selective media be autoclaved?
Not always. Some media containing dyes or selective inhibitors lose their selectivity if overheated and should only be heated until fully dissolved, without autoclaving. Follow the preparation instructions for this product, and contact us if you are unsure.
03How much powder per litre?
Use 37 g per litre of deionised water; preparation and sterilisation conditions are given on the specification sheet.
04Which organisms is it suitable for?
Coliforms, Gram-negative, E. coli, Escherichia coli, Klebsiella aerogenes, Enterococcus faecalis. See the cultural response table and the specification sheet.
05What are the equivalent brand products and standard methods?
Cross-reference: BD Difco EC Medium, Oxoid EC Broth, Merck EC Broth. Standard methods: ISO 7251, FDA BAM. Formulations may differ slightly between makers; refer to the specification sheet.
06How is this product prepared?
Suspend 37 g of powder in 1 L of purified water. Heat with continuous stirring and bring to the boil for 1 minute. Dispense into tubes containing inverted Durham tubes. Sterilize by autoclaving at 121°C for 15 minutes. Test the finished medium for performance using stable, standard control cultures.
07Is there a non-Halal version?
Yes. This is the Halal certified version; an equivalent standard version is also available.
08How do I request a bulk quotation, and can you provide a COA?
Yes. This product is available in 500 g, 5 kg, 25 kg. Tell us your application and volume when requesting a quotation; we reply within one working day and can supply the COA, specification sheet, and technical data sheet.
Used in these applications
Further reading
- FDA BAM Culture Media Cross-Reference: Which Media Each BAM Chapter Uses and the STBIO EquivalentAerobic plate count, coliforms and E. coli, Salmonella, Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, Vibrio, Clostridium perfringens, yeasts and moulds and Cronobacter: the media named in each FDA Bacteriological Analytical Manual chapter, matched to Taiwan-made dehydrated media for US laboratories qualifying a second source.
- Which Culture Media Do Taiwan FDA Food Microbiology Methods Specify? Cross-Reference for 21 Announced MethodsAerobic plate count, coliforms, E. coli, Enterobacteriaceae, Salmonella, Staphylococcus aureus, Listeria monocytogenes, lactic acid bacteria, yeasts and moulds, Bacillus cereus, Vibrio parahaemolyticus, Clostridium perfringens and Cronobacter: the media named in each Taiwan FDA (TFDA) announced method, matched to Taiwan-made products.
References
- 1. Hajna A. A. and Perry C. A., 1943. Comparative study of presumptive and confirmative media for bacteria of the coliform group and for fecal streptococci. Am. J. Public Health, 33:550-556.
- 2. American Public Health Association, Standard Methods for the Examination of Water and Wastewater, current edition, APHA Press, Washington, D.C.