Skip to product information
Request a Quote
↓
+ β-gur substrate cleaved → blue-indigo component
↓
= Dark blue to violet colony
↓
β-gur substrate NOT cleaved (no β-gur enzyme)
↓
= Salmon-pink to red colony
AuSaMicS ECC Agar — E. coli & Coliform Chromogenic Medium (AS-1438)
$145.00 AUD
AuSaMicS ECC Agar — E. coli & Coliform Detection Medium
Simultaneous Detection and Differentiation of E. coli and Total Coliforms in a Single Plate | Dual Chromogenic Enzyme Substrate System | Cat. No. AS-1438
Cat. No. AS-1438 pH 7.0 ± 0.2 ⚠ DO NOT AUTOCLAVE 🔵 E. coli → Blue-Violet 🔴 Coliforms → Salmon-Red ✓ ISO 9308-1:2014 ✓ AS/NZS 4276 Series 🇦🇺 Made in Melbourne ⚡ Same-Week Dispatch
E. coli
Dark blue to violet
Total Coliforms
Salmon-pink to red
Non-coliforms
Colourless / inhibited
Cat. No.
AS-1438
pH (25°C)
7.0 ± 0.2
Incubation
36±2°C / 21±3h
E. coli
Blue-Violet
Coliforms
Salmon-Red
📄 Full DocumentationCOA, TDS & SDS every batch
🇦🇺 Australian StockNo import delays
⚡ Same-Week DispatchMelbourne warehouse
🔬 Technical SupportDirect from our team
Overview
ECC Agar (AS-1438) is a selective and differential chromogenic culture medium for the simultaneous detection and enumeration of E. coli and total coliform bacteria from a single plate, without the need for confirmation steps. The medium uses a dual chromogenic enzyme substrate system — a β-D-galactosidase chromogenic substrate for all coliforms, and a β-D-glucuronidase chromogenic substrate for E. coli specifically — to produce visually distinct colony colours that allow immediate differentiation.
ECC Agar is compliant with ISO 9308-1:2014 — the current international standard for E. coli and coliform detection in water by membrane filtration — and is widely used in water quality testing, food microbiology, environmental monitoring, and pharmaceutical QC laboratories across Australia and internationally.
The Dual Chromogenic System — How It Works
Substrate 1 — β-D-galactosidase chromogenic substrate:
All coliform bacteria produce β-D-galactosidase, which cleaves this substrate to release a salmon/pink chromophore. This produces salmon-pink to red colonies for all coliforms, including E. coli.
Substrate 2 — β-D-glucuronidase chromogenic substrate:
E. coli specifically produces β-D-glucuronidase, which cleaves this substrate to release a blue-indigo chromophore. When combined with the salmon colour from the first substrate, the result is dark blue to violet colonies — a visually unambiguous signal for E. coli.
Result by colony colour:
🔵 Blue-violet = E. coli (both enzymes present)
🔴 Salmon-pink to red = other coliforms (β-gal only, no β-glucuronidase)
⚪ Colourless / no growth = non-coliforms (suppressed by Tergitol 7)
All coliform bacteria produce β-D-galactosidase, which cleaves this substrate to release a salmon/pink chromophore. This produces salmon-pink to red colonies for all coliforms, including E. coli.
Substrate 2 — β-D-glucuronidase chromogenic substrate:
E. coli specifically produces β-D-glucuronidase, which cleaves this substrate to release a blue-indigo chromophore. When combined with the salmon colour from the first substrate, the result is dark blue to violet colonies — a visually unambiguous signal for E. coli.
Result by colony colour:
🔵 Blue-violet = E. coli (both enzymes present)
🔴 Salmon-pink to red = other coliforms (β-gal only, no β-glucuronidase)
⚪ Colourless / no growth = non-coliforms (suppressed by Tergitol 7)
Colony Colour Guide
🔵 DARK BLUE TO VIOLET
E. coli
β-D-galactosidase + β-D-glucuronidase
Count separately
≥95% of E. coli strains
🔴 SALMON-PINK TO RED
Total coliforms (non-E. coli)
β-D-galactosidase only
Count separately
Klebsiella, Enterobacter, Citrobacter
⚪ COLOURLESS / NONE
Non-coliforms
Neither enzyme present
Suppressed or no colour
Do not count
How to count and report (ISO 9308-1:2014):
E. coli count = number of dark blue to violet colonies on the membrane.
Total coliform count = blue-violet colonies + salmon-pink/red colonies (sum of both colour groups).
Report as CFU per 100 mL of sample volume filtered.
E. coli count = number of dark blue to violet colonies on the membrane.
Total coliform count = blue-violet colonies + salmon-pink/red colonies (sum of both colour groups).
Report as CFU per 100 mL of sample volume filtered.
⚠️ Aeromonas spp. false positives: Some Aeromonas species are oxidase-positive but may produce β-glucuronidase, generating blue-violet colonies on ECC Agar. ISO 9308-1:2014 recommends performing an oxidase test on suspect colonies when Aeromonas is a concern (environmental and surface water samples). Oxidase-positive blue-violet colonies should not be counted as E. coli.
Detection Pathways
🔵 E. coli Detection Pathway
β-gal substrate cleaved → salmon component↓
+ β-gur substrate cleaved → blue-indigo component
↓
= Dark blue to violet colony
🔴 Other Coliform Detection Pathway
β-gal substrate cleaved → salmon component↓
β-gur substrate NOT cleaved (no β-gur enzyme)
↓
= Salmon-pink to red colony
Applications
💧
Drinking Water
ISO 9308-1:2014 — membrane filtration, 100 mL sample
🏊
Recreational Water
Bathing water, pools, beach water compliance
🌊
Environmental Water
Rivers, lakes, stormwater, irrigation water
🍕
Food & Dairy
Process water, hygiene monitoring, product testing
💊
Pharmaceutical QC
Process water, USP/EP water testing for coliforms
🏭
Environmental Monitoring
Surface sampling, wastewater, effluent compliance
Regulatory Standards
ISO 9308-1:2014Water quality — E. coli and coliforms — Part 1: Membrane filtration (primary standard for this medium)
ISO 9308-2:2012Part 2: Most Probable Number method
ISO 7218:2007Microbiology of food — General requirements for microbiological examinations
AS/NZS 4276 seriesAustralian Standard — Water microbiology (relevant parts)
ADWG 2022Australian Drinking Water Guidelines — microbiological compliance
ISO 11133:2014Culture media performance testing — QC requirements
ECC Agar vs Other E. coli / Coliform Detection Media
| Medium | E. coli | Total Coliforms | Temp | Standard |
|---|---|---|---|---|
| ECC Agar (AS-1438) ★ | 🔵 Blue-violet | 🔴 Salmon-red | 36±2°C | ISO 9308-1:2014 |
| TBX Agar | 🟢 Blue-green (β-gur only) | No differentiation | 44°C | ISO 16649-2 |
| m-FC Agar (AS-1405) | 🔵 Blue (all thermotolerant) | No differentiation | 44.5°C | ISO 9308-1; APHA 9222D |
| m-Endo Agar | Part of total coliforms | 🔴 Red + metallic sheen | 35°C | APHA 9222B |
| Chromocult® Coliform Agar | 🔵 Blue (β-gur) | 🔴 Salmon (β-gal) | 36±2°C | ISO 9308-1:2014 (reference) |
FAQs
❓ Can I detect both E. coli and total coliforms from a single plate?
Yes — this is the key advantage of ECC Agar. A single plate after 21 ± 3 hours incubation gives you: (1) the E. coli count directly from blue-violet colonies, and (2) the total coliform count from the sum of all blue-violet + salmon-pink/red colonies. No separate plates or confirmation steps are required under ISO 9308-1:2014 for routine testing.
❓ What about E. coli strains that are β-glucuronidase negative?
Approximately 94–96% of E. coli strains are β-D-glucuronidase positive and produce the characteristic blue-violet colour on ECC Agar. The notable exception is E. coli O157:H7, which is β-glucuronidase negative in approximately 80–90% of strains — these will appear salmon-pink (counted as coliforms, not E. coli). For food safety testing specifically targeting O157:H7, a dedicated medium is required. For routine water quality monitoring per ISO 9308-1, the false-negative rate for E. coli is within acceptable method performance limits.
❓ Why must ECC Agar NOT be autoclaved?
The chromogenic substrates — Salmon-GAL and X-Glucuronide — are heat-sensitive. Autoclaving at 121°C degrades these compounds, eliminating the colour development that is the medium's primary detection mechanism. The correct preparation is: dissolve by heating to boiling (or just below boiling) with agitation until completely dissolved, then cool to 45–50°C before pouring. Some manufacturers specify a maximum of one minute at boiling. Do not over-boil.
❓ What is Tergitol 7 and why is it in this medium?
Tergitol 7 (Sodium Heptadecyl Sulphate, 0.15 g/L) is the primary selective agent in ECC Agar. It inhibits the growth of Gram-positive organisms (enterococci, staphylococci) and some Gram-negative non-coliforms, without significantly affecting the growth of the target coliforms and E. coli. It was specifically chosen for ISO 9308-1:2014 because it provides clean selectivity without suppressing stressed or injured coliform cells, which is important for water samples that may contain chlorine-stressed organisms.
❓ What incubation temperature does ISO 9308-1:2014 specify?
36 ± 2°C for 21 ± 3 hours. Note that the original fayel اصلی in this document incorrectly stated 35–37°C. ISO 9308-1:2014 specifies 36°C as the target, with ±2°C tolerance (34–38°C) — not the narrower 35–37°C range. The 21 ± 3h incubation time is also specifically stated in the ISO method. Verify your incubator calibration before routine use.
Cross-Reference / Equivalents
| Manufacturer | Product Name | Cat. No. | Notes |
|---|---|---|---|
| CHROMagar | CHROMagar ECC | ECC011 | Original CHROMagar formulation; reference brand |
| Merck / Sigma-Aldrich | Chromocult Coliform Agar | 110426 | ISO 9308-1:2014 validation medium |
| HiMedia | HiCrome ECC Agar | M1831 | Same dual chromogenic principle |
| Thermo Scientific / Oxoid | Chromogenic Coliform Agar | CM1046 | CCA equivalent |
Related Products
Product Specifications
| Product Name | ECC Agar — E. coli & Coliform Chromogenic Medium |
| Catalogue Number | AS-1438 |
| Synonyms | ECC Agar; E. coli Coliform Detection Medium; Chromogenic Coliform Agar (CCA); E. coli & Coliform Chromogenic Medium |
| Standards | ISO 9308-1:2014 | ISO 9308-2:2012 | ISO 7218:2007 | AS/NZS 4276 series | ISO 11133:2014 |
| Medium Type | Selective differential chromogenic agar — dual enzyme substrate system |
| Final pH at 25°C | 7.0 ± 0.2 |
| Sterilisation | DO NOT AUTOCLAVE — heat to boiling to dissolve, then cool to 45–50°C |
| Appearance (powder) | Beige to light tan, free-flowing homogeneous powder |
| Appearance (prepared) | Light amber to pale yellow, slightly opalescent gel |
| Incubation | 36 ± 2°C for 21 ± 3 hours (ISO 9308-1:2014) — aerobically |
| Storage (powder) | 2–25°C, dry, tightly sealed, away from direct light |
| Storage (prepared plates) | 2–8°C; use within 2 weeks. Protect from light — chromogenic substrates are light-sensitive. |
| HS Tariff Code | 3821.00.00 |
Formula — Per Litre (CHROMagar ECC / ISO 9308-1 CCA Reference)
| Ingredient | g / L | Role |
|---|---|---|
| Peptone (Enzymatic Digest of Casein) | ~15.0 | Primary nitrogen — amino acids, peptides, growth factors |
| Yeast Extract | ~3.0 | B-vitamins, trace elements, growth co-factors |
| Sodium Pyruvate | ~1.0 | Energy source; supports recovery of stressed/injured coliform cells |
| Sorbitol | ~1.0 | Carbohydrate; supports coliform growth and recovery |
| Sodium Chloride | 5.0 | Osmotic balance |
| Disodium Hydrogen Phosphate (Na₂HPO₄) | ~2.7 | pH buffer component |
| Sodium Dihydrogen Phosphate (NaH₂PO₄) | ~2.2 | pH buffer component |
| Tergitol 7 (Sodium Heptadecyl Sulphate) | 0.15 | Primary selective agent — suppresses Gram-positive organisms without affecting coliforms |
| β-D-galactosidase chromogenic substrate | Chromogenic | Cleaved by β-D-galactosidase — produces salmon-red colour in ALL coliforms (E. coli and non-E. coli) |
| β-D-glucuronidase chromogenic substrate | Chromogenic | Cleaved by β-D-glucuronidase — produces blue-indigo colour in E. coli specifically (not present in most other coliforms) |
| IPTG (Isopropyl-β-D-thiogalactopyranoside) | 0.1 | Inducer — enhances β-D-galactosidase expression, improves detection of weakly positive coliforms |
| Agar | ~12–15 | Solidifying agent |
| Total dissolution | ~36–42 g/L | pH 7.0 ± 0.2 at 25°C | DO NOT AUTOCLAVE — heat to boiling to dissolve | Cool to 45–50°C before pouring |
Preparation Protocol
⚠️ DO NOT AUTOCLAVE. Chromogenic substrates (Salmon-GAL, X-Glucuronide) are degraded by autoclaving. Use boiling water bath or direct heat only.
1
Suspend the required amount of dehydrated ECC Agar (AS-1438) in purified or distilled water per the label dissolution (g/L). Mix well.
2
Heat with frequent agitation to boiling. Continue heating for 1 minute to dissolve completely. Avoid prolonged boiling.
3
Cool to 45–50°C in a water bath. Do not allow to set — pour while still molten.
4
Pour 10–15 mL per 90 mm Petri dish. Allow to solidify on a level surface.
5
Dry the agar surface — leave lids ajar at room temperature for 30–60 minutes, or dry at 37°C for 30 min. Surface moisture causes colony spreading.
6
For membrane filtration (water testing): place membrane filter grid-side up on ECC Agar. Incubate at 36 ± 2°C for 21 ± 3 hours. Count blue-violet (E. coli) and salmon-red (coliforms) colonies separately.
QC Organisms & Expected Results
| Organism (ATCC) | Expected Growth | Colony Colour | Interpretation |
|---|---|---|---|
| Escherichia coli ATCC 25922 | Good growth; ≤100 CFU | Dark blue to violet | E. coli ✓ |
| Escherichia coli ATCC 8739 | Good growth; ≤100 CFU | Dark blue to violet | E. coli ✓ |
| Enterobacter aerogenes / Klebsiella aerogenes ATCC 13048 | Good growth; ≤100 CFU | Salmon-pink to red | Coliform (non-E. coli) ✓ |
| Citrobacter freundii ATCC 43864 | Good growth | Salmon-pink to red | Coliform ✓ |
| Enterococcus faecalis ATCC 19433 | Inhibited / partial growth | No colour | Non-coliform — inhibited ✓ |
| Staphylococcus aureus ATCC 25923 | Inhibited / no growth | No colour | Non-coliform — inhibited ✓ |
Literature & References
| # | Reference |
|---|---|
| 1 | ISO 9308-1:2014. Water quality — Enumeration of Escherichia coli and coliform bacteria — Part 1: Membrane filtration method for waters with low bacterial background flora. Geneva: ISO; 2014. [Primary standard] |
| 2 | Farnleitner AH, et al. Performance validation of chromogenic coliform agar for the enumeration of E. coli and coliform bacteria. J Appl Microbiol. 2004. [CCA ISO 9308-1 validation study] |
| 3 | Manafi M, Kneifel W. A combined chromogenic-fluorogenic medium for the simultaneous detection of total coliforms and E. coli in water. Zentralbl Hyg Umweltmed. 1990;189:225–234. |
| 4 | ISO 7218:2007. Microbiology of food and animal feeding stuffs — General requirements and guidance for microbiological examinations. Geneva: ISO; 2007. |
| 5 | ISO 11133:2014. Performance testing of culture media. Geneva: ISO; 2014. |
📄 Full 16-section GHS SDS available (Australian WHS Regulations 2023 / GHS 7th Edition) — support@ausamics.com.au
Section 1 — Identification
| Product Name | ECC Agar — E. coli & Coliform Chromogenic Medium |
| Catalogue No. | AS-1438 |
| Intended Use | Selective differential chromogenic culture medium for detection and enumeration of E. coli and total coliforms. Laboratory and environmental testing use only. |
| Supplier | AuSaMicS Pty Ltd | ABN 56 676 640 467 |
| Address | 31 Longview CT, Thomastown VIC 3074, Australia |
| Emergency | Poisons Information Centre: 13 11 26 (24 hr) |
| Phone | +61 412 520 598 | support@ausamics.com.au |
Section 2 — Hazard Identification (GHS 7th Ed / WHS 2023)
| GHS Classification | NOT classified as a hazardous substance under Australian WHS Regulations 2023 at intended use concentrations. GHS07 (irritant) may apply for dust exposure during bulk weighing — apply precautionary handling. |
| Signal Word | Warning (dust inhalation precautionary only) |
| Hazard Statement | H335 — may cause respiratory irritation (precautionary; bulk powder handling) |
| Other Hazards | Combustible powder. Chromogenic substrates at 0.1–0.2 g/L level: not classified hazardous. Tergitol 7 at 0.15 g/L: mild irritant at use level. |
Composition
| Component | g/L | CAS | Hazard |
|---|---|---|---|
| Peptone | ~15 | 73049-73-7 | Not hazardous |
| Yeast Extract | ~3 | 8013-01-2 | Not hazardous |
| Sodium Chloride | 5.0 | 7647-14-5 | Not hazardous at use level |
| Sodium Pyruvate | ~1 | 113-24-6 | Not hazardous |
| Phosphate buffer salts | ~5 | Various | Not hazardous at use level |
| Tergitol 7 (Sodium Heptadecyl Sulphate) | 0.15 | 1462-54-0 | Mild skin irritant at high concentrations; not significant at 0.15 g/L |
| Salmon-GAL + X-Glucuronide + IPTG | Trace | Various | Not classified hazardous at use concentrations |
| Agar | ~12–15 | 9002-18-0 | Not hazardous |
| PPE | P1 respirator when weighing bulk powder; safety glasses; nitrile gloves; lab coat |
| Waste | Autoclave 121°C / 15 min before disposal as microbiological waste |
| Storage | Store dry, cool (2–25°C), protected from direct sunlight and moisture |
| Transport | Not dangerous goods — ADG, IMDG, IATA |
Quality Specifications
| Parameter | Specification | Method |
|---|---|---|
| Appearance (powder) | Beige to light tan, free-flowing, homogeneous powder | Visual |
| Appearance (prepared) | Light amber, slightly opalescent; firm agar gel | Visual after dissolution |
| pH (prepared, 25°C) | 7.0 ± 0.2 | pH meter (calibrated) |
| Moisture Content | ≤8.0% (w/w) | Loss on drying |
| Growth — E. coli ATCC 25922 | Good growth; dark blue to violet; 36°C; 21–24h; ≤100 CFU | ISO 11133:2014 |
| Growth — E. coli ATCC 8739 | Good growth; dark blue to violet; 36°C; 21–24h | ISO 11133:2014 |
| Growth — K. aerogenes ATCC 13048 | Good growth; salmon-pink to red; 36°C; 21–24h; ≤100 CFU | ISO 11133:2014 |
| Inhibition — E. faecalis ATCC 19433 | Inhibited / no typical colour; ≤100 CFU inoculum | Selectivity check |
| Inhibition — S. aureus ATCC 25923 | Inhibited / no typical colour | Selectivity check |
| Recovery | ≥70% vs reference medium (TSA) | ISO 11133:2014 |
| Batch COA | Available every production lot | Included with every order |
Pack Sizes
| 100 g | Method validation, small laboratory |
| 500 g | Routine water testing laboratory — most popular |
| 1 kg | High-throughput testing laboratory |
| 5 kg, 10 kg, 25 kg | Large facility, bulk procurement, government contract |
| Custom | Contact support@ausamics.com.au for institutional/tender quantities |
Manufacturing & Documentation
Manufactured by AuSaMicS Pty Ltd
31 Longview CT, Thomastown VIC 3074, Australia | ABN 56 676 640 467
✓ Formulated per CHROMagar ECC / ISO 9308-1:2014 CCA reference specification
✓ Dual chromogenic substrate system: β-D-galactosidase substrate (coliforms → salmon-red) + β-D-glucuronidase substrate (E. coli → blue-violet)
✓ Batch QC per ISO 11133:2014 — pH, growth promotion, inhibition, colony colour
✓ COA, TDS, SDS included with every order
✓ Australian stock — same-week dispatch, no import delays
✓ Incubation per ISO 9308-1:2014: 36 ± 2°C / 21 ± 3h
31 Longview CT, Thomastown VIC 3074, Australia | ABN 56 676 640 467
✓ Formulated per CHROMagar ECC / ISO 9308-1:2014 CCA reference specification
✓ Dual chromogenic substrate system: β-D-galactosidase substrate (coliforms → salmon-red) + β-D-glucuronidase substrate (E. coli → blue-violet)
✓ Batch QC per ISO 11133:2014 — pH, growth promotion, inhibition, colony colour
✓ COA, TDS, SDS included with every order
✓ Australian stock — same-week dispatch, no import delays
✓ Incubation per ISO 9308-1:2014: 36 ± 2°C / 21 ± 3h
⚠️ For laboratory, water quality testing, food microbiology, environmental testing, and research use only. Not for food, therapeutic, veterinary, or direct human use. Autoclave all inoculated material before disposal.