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R2A Broth | Low-Nutrient Water Enrichment Medium | Ausamics
$35.00 AUD
Product Identification
| Catalog Number | AS-1397 |
| Product Name | R2A Broth (Reasoner's 2A Broth) |
| Format | Dehydrated powder — reconstitute as liquid broth |
| Medium Type | Low-nutrient, non-selective liquid medium |
| Final pH (prepared) | 7.2 ± 0.2 at 25 °C |
| Preparation | Dissolve 3.4 g per litre of purified water |
| Intended Use | For Laboratory Use Only — Not for human, animal, or food use |
Overview
R2A Broth (Reasoner's 2A Broth) is a low-nutrient, non-selective liquid culture medium originally formulated by Reasoner and Geldreich (1985) for the recovery and cultivation of heterotrophic bacteria from treated drinking water and environmental samples. Its deliberately diluted nutrient composition supports the growth of oligotrophic, stressed, and slow-growing microorganisms that are frequently inhibited in conventional nutrient-rich media.
AS-1397 is the internationally recognised broth format for heterotrophic plate count (HPC) enrichment, Most Probable Number (MPN) assays, biofilm studies, and environmental microbial ecology. It is validated per APHA Standard Methods 9215, US EPA Method 9215, ISO 8245, and ASTM D9217.
Key Features
- Low-nutrient formulation (3.4 g/L total) — promotes recovery of oligotrophic and stressed bacteria
- Non-selective — supports a wide variety of environmental and water-borne microorganisms
- Liquid broth format — ideal for enrichment cultures, MPN assays, suspension cultures, and biofilm systems
- Balanced 8-component formula — includes pyruvate, soluble starch, and amino acid sources for diverse metabolic types
- Standardised — validated per APHA 9215, US EPA 9215, ISO 8245, and ASTM D9217
- Compatible with 7–14 day incubation — formulated for extended oligotrophic culture without medium deterioration
Composition (per litre of prepared medium)
| Ingredient | Amount (g/L) | Function |
|---|---|---|
| Proteose Peptone | 0.5 | Complex nitrogen, amino acid, and growth factor source |
| Casamino Acids | 0.5 | Defined amino acid mixture; supports fastidious organisms |
| Yeast Extract | 0.5 | B-vitamins, nucleotides, and accessory growth factors |
| Dextrose (D-Glucose) | 0.5 | Readily metabolisable carbon and energy source |
| Soluble Starch | 0.5 | Complex carbohydrate; mimics environmental polysaccharides |
| Dipotassium Phosphate (K₂HPO₄) | 0.3 | Phosphate buffer and essential phosphorus source |
| Magnesium Sulfate (MgSO₄·7H₂O) | 0.05 | Essential magnesium cofactor; sulfur source |
| Sodium Pyruvate | 0.3 | Rapidly catabolised carbon source; supports stressed-cell recovery |
| Purified Water | q.s. 1 L | — |
Preparation (Summary)
- Dissolve 3.4 g in 1 L of purified water. Mix with gentle agitation until fully dissolved.
- Dispense into flasks, tubes, or containers as required.
- Autoclave at 121 °C for 15 minutes. Do not over-autoclave.
- Cool to 20–28 °C before inoculation. Inspect: clear to slightly hazy, light straw colour expected.
Incubation & Interpretation
| Temperature | 20–28 °C (environmental/water organisms); 35 °C for faecal indicators |
| Duration | 7–14 days for oligotrophic bacteria; 24–72 h for faster-growing strains |
| Positive Result | Turbidity, visible biomass, pellicle, or sediment formation |
| Negative Result | Clear broth throughout full incubation period |
| Further Testing | Plate onto R2A Agar; Gram stain; microscopy; molecular identification |
⚠ For Laboratory Use Only. Environmental water samples and inoculated media may contain pathogenic organisms. Handle in accordance with applicable Biosafety Level (BSL) requirements. Neutralise residual chlorine in water samples with sodium thiosulfate before inoculation.
Performance Specifications
| Parameter | Specification | Method |
|---|---|---|
| Appearance (powder) | Beige to pale cream powder | Visual inspection |
| Final pH (prepared, 25 °C) | 7.2 ± 0.2 | Calibrated pH electrode |
| Appearance (prepared broth) | Clear to slightly hazy; light straw colour | Visual inspection |
| Sterility (prepared) | No turbidity after 14 d at 28 °C | USP <71> |
| Productivity — E. coli ATCC 25922 | Growth within 24–48 h at 35 °C | APHA 9215 / ISO 8245 |
| Productivity — P. aeruginosa ATCC 27853 | Growth within 48–72 h at 28 °C | APHA 9215 / ISO 8245 |
| Productivity — B. diminuta ATCC 19146 | Growth within 7 days at 28 °C | ISO 8245 |
| Moisture Content (powder) | < 5.0% | Loss on drying, 105 °C |
Preparation Protocol
Dissolution:
Dissolve 3.4 g in 1 L of purified (Milli-Q or Type 1) water with gentle agitation at room temperature. Solution should be clear to slightly hazy. Do not boil.
Sterilisation:
Autoclave at 121 °C for 15 minutes. Do not over-autoclave — excessive heat will caramelise carbohydrate components, causing browning and performance degradation.
Inoculation:
Cool to 20–28 °C. Neutralise residual disinfectants in water samples (e.g. 0.1 mL of 3% sodium thiosulfate per 100 mL sample) before inoculation.
Key Limitations
- Non-selective — strict aseptic technique is essential to avoid environmental contamination.
- May not support growth of copiotrophic (high-nutrient-requiring) organisms.
- Residual disinfectants (chlorine, chloramine) in water samples will inhibit recovery — neutralise before inoculation.
- Turbidity alone is not definitive; assess all visual cues and use uninoculated controls.
- Over-autoclaving will degrade carbohydrate components.
Storage
| Dehydrated Powder | 15–30 °C; dry; original tightly sealed container |
| Prepared Broth | 2–8 °C; protected from light; use within 4 weeks |
| Shelf Life (powder) | As stated on label (typically 3 years from manufacture) |
Technical Data Sheet represents typical values. AuSaMiCS Pty Ltd reserves the right to update specifications without notice. Issue Date: March 2025 | Version 1.0
Section 1 — Identification
| Product | R2A Broth (Reasoner's 2A Broth) |
| Catalog No. | AS-1397 |
| Use | Low-nutrient microbiological liquid medium — laboratory research only |
| Supplier | AuSaMiCS Pty Ltd, 31 Longview CT, Thomastown VIC 3074 |
| Emergency | Poisons Information Centre: 13 11 26 (Australia, 24 hr) |
Section 2 — Hazard Identification
GHS Classification: NOT classified as a hazardous substance under Australian WHS Regulations 2017 at typical laboratory quantities.
Precautionary Statements
P260 Do not breathe dust | P264 Wash hands after handling | P270 Do not eat/drink/smoke | P501 Dispose per local regulations
Biological Hazard Note
Environmental water samples and inoculated media may contain pathogenic or opportunistic microorganisms. Handle all inoculated media in accordance with applicable Biosafety Level (BSL) requirements and institutional biosafety guidelines.
Sections 4–8 — First Aid, Fire, Spill, Handling & PPE (Summary)
| Topic | Key Guidance |
|---|---|
| Inhalation | Remove to fresh air. Seek medical attention if symptoms persist. |
| Skin Contact | Wash with soap and water ≥ 15 min. Remove contaminated clothing. |
| Eye Contact | Irrigate with water ≥ 15 min. Seek immediate medical attention. |
| Ingestion | Do not induce vomiting. Rinse mouth. Seek medical attention. |
| Fire | Not flammable. Use CO₂ or dry chemical powder. |
| Spill (powder) | Sweep up; avoid dust generation. Collect in sealed labelled container. |
| Spill (inoculated) | Treat as biological hazard. Decontaminate per institutional biosafety protocol. |
| PPE | Nitrile gloves, safety goggles, lab coat. Biosafety cabinet for inoculated work. |
Section 13 — Disposal
Uninoculated medium: Dispose via licensed chemical waste contractor or as general laboratory waste per local EPA regulations.
Inoculated / used broth: Autoclave at 121 °C for 30 minutes to inactivate biological material before disposal. Dispose of decontaminated liquid per institutional policy.
Section 15 — Regulatory
| WHS Regulations 2017 | Compliant — not classified as hazardous |
| ARTG / TGA | Not registered — laboratory use only |
| Transport | Not classified as dangerous goods (ADG / IATA / IMDG) |
Summary SDS preview only. Full GHS-compliant 16-section SDS available for download. Issue Date: March 2025 | Version 1.0 | Prepared per Australian WHS Regulations 2017.
Lot & Product Details
| Product Name | R2A Broth (Reasoner's 2A Broth) |
| Catalog Number | AS-1397 |
| Lot Number | AS1397-250301 |
| Format | Dehydrated powder, 500 g |
| Date of Manufacture | March 2025 |
| Expiry Date | March 2028 |
| Storage | 15–30 °C, dry, tightly sealed original container |
Quality Test Results
| Test Parameter | Specification | Result | Method |
|---|---|---|---|
| Appearance (powder) | Beige to pale cream powder | CONFORMS | Visual inspection |
| Final pH (prepared, 25 °C) | 7.2 ± 0.2 | 7.2 | Calibrated pH electrode |
| Appearance (prepared broth) | Clear to slightly hazy; straw colour | CONFORMS | Visual inspection |
| Moisture Content (powder) | < 5.0% | 1.9% | Loss on drying, 105 °C |
| Sterility (prepared) | No turbidity after 14 d at 28 °C | CONFORMS | USP <71> |
| Productivity — E. coli ATCC 25922 | Growth within 24–48 h at 35 °C | CONFORMS | APHA 9215 / ISO 8245 |
| Productivity — P. aeruginosa ATCC 27853 | Growth within 48–72 h at 28 °C | CONFORMS | APHA 9215 / ISO 8245 |
| Productivity — B. diminuta ATCC 19146 | Growth within 7 days at 28 °C | CONFORMS | ISO 8245 |
| Label / Packaging Integrity | Correct label; intact seal | CONFORMS | Visual inspection |
Authorisation
| Analysed By | AuSaMiCS Quality Control Laboratory |
| Authorised By | Hassan Salimi, Founder & Technical Director, AuSaMiCS Pty Ltd |
| Date of Issue | March 2025 |
| COA Reference | AS1397-250301-COA-001 |
This COA is specific to Lot AS1397-250301 only. Not transferable to other lots. © 2025 AuSaMiCS Pty Ltd. Unauthorised reproduction prohibited.