Skip to product information
Request a Quote
Mueller Hinton Broth AS‑1439 | Microbiology Culture Medium | Ausamics Life Science
$35.00 AUD
Mueller Hinton Broth (MHB)
General-Purpose Microbiological Culture Medium | Low Thymidine Formulation | Cat. No. AS-1439
Cat. No. AS-1439 pH 7.3 ± 0.2 21 g/L Beef Infusion + Casein Hydrolysate + Starch ✓ Low Thymidine / Thymine ✓ Sigma 70192 Equivalent Boil Before Autoclaving 🇦🇺 Made in Melbourne ⚡ Same-Week Dispatch
Cat. No.
AS-1439
pH (25°C)
7.3 ± 0.2
Dissolution
21 g/L
Preparation
Boil → Autoclave
Incubation
35 ± 2°C / 18–24h
📄 Full DocumentationCOA, TDS & SDS every batch
🇦🇺 Australian StockNo import delays
⚡ Same-Week DispatchMelbourne warehouse
🔬 Technical SupportDirect from our team
Overview
Mueller Hinton Broth (AS-1439) is a general-purpose liquid culture medium formulated for the cultivation of non-fastidious aerobic and facultatively anaerobic bacteria. Originally developed by Mueller and Hinton (1941) for the primary isolation of pathogenic Neisseria species, this three-component formulation — Beef Infusion Solids, Casein Acid Hydrolysate, and Starch — has become one of the most widely used microbiological broths for general cultivation, disk diffusion inoculum preparation, and antimicrobial applications.
AS-1439 follows the standard formula as described in the Sigma-Aldrich 70192 specification: pH 7.3 ± 0.2, dissolution 21 g/L, with low thymidine and thymine content. An important preparation note: bring to the boil before autoclaving to ensure the starch disperses uniformly and does not settle at the bottom of the container.
Which Mueller Hinton Product Do You Need?
| Application | Recommended Product | Why |
|---|---|---|
| General cultivation, disk diffusion inoculum, research | AS-1439 — This product | Standard MHB; no cation adjustment needed |
| Broth microdilution MIC testing with standardized Ca²⁺/Mg²⁺ | AS-1300 (CAMHB) | Prepared with standardized calcium and magnesium supplementation |
| Disk diffusion susceptibility testing (Kirby-Bauer) | AS-1299 (Mueller Hinton Agar) | Solid medium required; broth only for inoculum prep |
Mode of Action — Three-Component Design
Beef Infusion Solids (2.0 g/L): Prepared from beef muscle infusion — provides a broad spectrum of amino acids, B-vitamins, carbon sources, sulphur compounds, and trace minerals. Supports rapid growth of a wide range of non-fastidious organisms including clinically important pathogens.
Casein Acid Hydrolysate (17.5 g/L): Primary nitrogen source. Acid hydrolysis of casein produces free amino acids and short peptides. The acid hydrolysis process naturally yields a product with low thymidine and thymine content — critical for sulfonamide and trimethoprim applications where thymidine in the medium would antagonise drug activity and produce false resistance results.
Starch (1.5 g/L): Functions as a protective colloid — adsorbs and neutralises fatty acids and other bacteriostatic or toxic substances that may be present in peptone components. This prevents non-specific growth inhibition. Starch hydrolysis during autoclaving also yields a small amount of glucose, providing an additional energy source. Note: starch settles during storage — boil before autoclaving to disperse uniformly.
Casein Acid Hydrolysate (17.5 g/L): Primary nitrogen source. Acid hydrolysis of casein produces free amino acids and short peptides. The acid hydrolysis process naturally yields a product with low thymidine and thymine content — critical for sulfonamide and trimethoprim applications where thymidine in the medium would antagonise drug activity and produce false resistance results.
Starch (1.5 g/L): Functions as a protective colloid — adsorbs and neutralises fatty acids and other bacteriostatic or toxic substances that may be present in peptone components. This prevents non-specific growth inhibition. Starch hydrolysis during autoclaving also yields a small amount of glucose, providing an additional energy source. Note: starch settles during storage — boil before autoclaving to disperse uniformly.
Key Features
🤔
Low Thymidine
Casein hydrolysate selected for minimal thymidine/thymine
🧪
Starch Detoxifier
Protective colloid — absorbs toxic metabolites from peptone
📊
Batch Consistency
Good batch-to-batch reproducibility for reliable results
💧
Clear Broth
Clear solution after preparation — easy turbidity assessment
🔬
Broad Spectrum
Supports growth of most non-fastidious aerobic pathogens
🧬
Versatile Base
Suitable for supplementation with blood, NaCl, or cations
Supplements for Specific Organisms
| Organism / Application | Supplement | Concentration | Note |
|---|---|---|---|
| Streptococcus spp. cultivation | Defibrinated sheep or horse blood | 5% v/v | Supports fastidious organisms |
| Methicillin / oxacillin susceptibility (Staphylococci) | Sodium Chloride (NaCl) | 2% w/v | Improves detection of heteroresistance |
| Trimethoprim / sulfonamide testing | Thymidine phosphorylase (if required) | Per validated protocol | Eliminates residual thymidine interference |
| Sulfonamide susceptibility — N. gonorrhoeae | Rabbit serum | Per validated protocol | Original Mueller Hinton recommendation |
FAQs
❓ Why must I boil the broth before autoclaving?
The starch component (1.5 g/L) tends to settle at the bottom of the container during dissolution. If you autoclave without first bringing the suspension to the boil, the starch may remain unevenly distributed — producing settled, clumped starch in the lower portion of the medium and a starch-deficient broth above. Boiling ensures uniform starch dispersion throughout the medium before sterilisation. This is noted in the HiMedia M173 specification for this formulation.
❓ What is the difference between AS-1439 and CAMHB AS-1300?
AS-1439 is the standard Mueller Hinton Broth formulation — the three-component base without supplemental cation adjustment. AS-1300 (CAMHB) is prepared with standardized calcium and magnesium supplementation targeting Ca²⁺ 20–25 mg/L and Mg²⁺ 10–12.5 mg/L as described in CLSI M07. For broth microdilution MIC testing where divalent cation levels are important for aminoglycoside, polymyxin, or tetracycline testing, use AS-1300. For general cultivation, disk diffusion inoculum preparation, and research where specific cation control is not required, AS-1439 is appropriate.
❓ Why is low thymidine content important?
Thymidine allows bacteria to bypass the folate synthesis pathway that trimethoprim and sulfonamides target. High thymidine in the broth antagonises these drugs, causing bacteria to appear resistant even when they are susceptible. Mueller Hinton Broth uses casein acid hydrolysate specifically selected for low thymidine and thymine content — verified by testing Enterococcus faecalis with sulfamethoxazole-trimethoprim (SXT) MIC values per NCCLS/CLSI methods.
❓ Is AS-1439 equivalent to Sigma-Aldrich 70192?
Yes — AS-1439 follows the same standard formula: Beef Infusion Solids 2.0 g/L, Casein Acid Hydrolysate 17.5 g/L, Starch 1.5 g/L, pH 7.3 ± 0.2, dissolution 21 g/L. Boil before autoclaving at 121°C / 10–15 min. Full COA supplied with every batch.
ⓘ Need standardized Ca²⁺ and Mg²⁺ for MIC testing?
Use AS-1300 — Cation-Adjusted Mueller Hinton Broth (CAMHB), prepared with standardized calcium and magnesium supplementation targeting CLSI M07 specification levels. AS-1300 has pH 7.3 ± 0.1 and is the appropriate choice when consistent divalent cation levels are important for your application.
Cross-Reference / Equivalents
| Manufacturer | Product Name | Cat. No. |
|---|---|---|
| Sigma-Aldrich / Merck | Mueller Hinton Broth (NutriSelect® Plus) | 70192 |
| Thermo Scientific / Oxoid | Mueller Hinton Broth | CM0405 |
| HiMedia | Mueller Hinton Broth No. 2 | M173 |
| BD Difco | Mueller Hinton Broth | 275730 |
Related Products
Product Specifications
| Product Name | Mueller Hinton Broth (Standard) |
| Catalogue Number | AS-1439 |
| Synonyms | MHB; MH Broth; Mueller-Hinton Broth; Antibacterial Potency Testing Broth |
| Commercial Equivalents | Sigma-Aldrich 70192 | Oxoid CM0405 | HiMedia M173 | BD Difco 275730 |
| Medium Type | General-purpose non-selective liquid broth |
| Dissolution | 21 g/L in purified or distilled water |
| Final pH at 25°C | 7.3 ± 0.2 |
| Preparation — Critical | Bring to boil before autoclaving to disperse starch uniformly. Autoclave 121°C / 10–15 minutes. DO NOT OVERHEAT. |
| Appearance (powder) | Light beige to cream, free-flowing, hygroscopic powder |
| Appearance (prepared) | Clear to very pale straw; no precipitate |
| Incubation | 35 ± 2°C for 18–24 hours in ambient air |
| Storage (powder) | Cool, dry, tightly sealed; hygroscopic — keep closed except during weighing |
| Storage (prepared broth) | 2–8°C up to 1 month |
| HS Tariff Code | 3821.00.00 |
Formula — Per Litre (Sigma-Aldrich 70192 Reference)
| Ingredient | g / L | Function |
|---|---|---|
| Beef Infusion Solids | 2.0 | Amino acids, B-vitamins, carbon, sulphur, minerals from beef infusion — broad nutritional support for non-fastidious organisms |
| Casein Acid Hydrolysate | 17.5 | Primary nitrogen source — free amino acids from acid hydrolysis. Selected for low thymidine and thymine content — important for sulfonamide/trimethoprim applications |
| Starch | 1.5 | Protective colloid — adsorbs toxic fatty acids and bacteriostatic substances. Yields small amount of glucose on hydrolysis. Boil before autoclaving to prevent settling. |
| Total | 21 g/L | pH 7.3 ± 0.2 at 25°C | Boil to dissolve → Autoclave 121°C / 10–15 min | DO NOT OVERHEAT |
⚠️ Starch settling: Unlike most broth media, Mueller Hinton Broth must be brought to a boil before autoclaving to ensure starch is uniformly dispersed. Failing to boil first results in uneven starch distribution — the protective colloid function will be inconsistent across tubes/bottles.
Preparation Protocol
1
Suspend 21 g of dehydrated Mueller Hinton Broth (AS-1439) in 1 litre of purified or distilled water. Mix well.
2
Heat with frequent agitation and bring to boil to dissolve completely and disperse starch uniformly. Do not proceed to autoclave without first boiling.
3
Dispense into tubes or bottles as required.
4
Sterilise by autoclaving at 121°C for 10–15 minutes. DO NOT OVERHEAT — excess heat degrades medium components and may alter pH.
5
Allow to cool. Verify pH with calibrated pH meter: acceptable range 7.1–7.5. Store at 2–8°C.
QC Performance Organisms
| Organism (ATCC) | Expected Result | Incubation |
|---|---|---|
| Escherichia coli ATCC 25922 | Good growth; turbid broth | 35±2°C / 18–24h |
| Staphylococcus aureus ATCC 25923 | Good growth; turbid broth | 35±2°C / 18–24h |
| Pseudomonas aeruginosa ATCC 27853 | Good growth; turbid broth | 35±2°C / 18–24h |
Literature & References
| # | Reference |
|---|---|
| 1 | Mueller JH, Hinton J. A protein-free medium for primary isolation of the Gonococcus and Meningococcus. Proc Soc Exp Biol Med. 1941;48:330–333. [Original medium] |
| 2 | Sigma-Aldrich / Merck. Mueller Hinton Broth NutriSelect® Plus, Cat. 70192. Product specification. [Reference formula for AS-1439] |
| 3 | Bauer AW, et al. Antibiotic susceptibility testing by a standardized single disk method. Am J Clin Pathol. 1966;45:493–496. [Kirby-Bauer disk diffusion — MHB inoculum] |
| 4 | CLSI. Methods for Dilution Antimicrobial Susceptibility Tests. CLSI Standard M07; current edition. [MHB base formulation reference] |
| 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 | Mueller Hinton Broth (Standard) |
| Catalogue No. | AS-1439 |
| Intended Use | General-purpose liquid culture medium for microbiological cultivation, disk diffusion inoculum preparation, and antimicrobial susceptibility applications. Laboratory 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. All components are food-grade or GRAS at supplied concentrations. |
| Signal Word | None required |
| Other Hazards | Combustible powder. Hygroscopic — absorbs moisture. Dust may cause mild respiratory irritation during bulk weighing. |
Composition
| Component | g/L | CAS | Hazard |
|---|---|---|---|
| Beef Infusion Solids | 2.0 | Mixture | Not hazardous |
| Casein Acid Hydrolysate | 17.5 | 65072-00-6 | Not hazardous |
| Starch | 1.5 | 9005-84-9 | Not hazardous |
| PPE | P1 respirator when weighing bulk powder; safety glasses; nitrile gloves; lab coat |
| Hygroscopic note | Keep container tightly sealed. Do not leave open during weighing. Hygroscopic clumping indicates moisture uptake — do not use clumped product. |
| Waste (inoculated) | Autoclave 121°C / 15 min before disposal as microbiological waste |
| Transport | Not dangerous goods — ADG, IMDG, IATA |
| Regulatory | Australian WHS Regulations 2023 | GHS 7th Edition | AICIS compliant |
Quality Specifications
| Parameter | Specification | Method |
|---|---|---|
| Appearance (powder) | Light beige to cream, free-flowing, hygroscopic powder | Visual |
| Appearance (prepared) | Clear to very pale straw; no significant precipitate | Visual after dissolution |
| pH (prepared, 25°C) | 7.3 ± 0.2 | pH meter (calibrated) |
| Dissolution | Complete at 21 g/L after boiling | Visual |
| Moisture Content | ≤5.0% (w/w) | Loss on drying |
| Growth — E. coli ATCC 25922 | Good growth; turbid; 35±2°C; 18–24h; ≤100 CFU | ISO 11133:2014 |
| Growth — S. aureus ATCC 25923 | Good growth; turbid; 35±2°C; 18–24h; ≤100 CFU | ISO 11133:2014 |
| Growth — P. aeruginosa ATCC 27853 | Good growth; turbid; 35±2°C; 18–24h; ≤100 CFU | ISO 11133:2014 |
| Batch COA | Available every production lot | Included with every order |
Manufacturing & Documentation
Manufactured by AuSaMicS Pty Ltd
31 Longview CT, Thomastown VIC 3074, Australia | ABN 56 676 640 467
✓ Formulated per Sigma-Aldrich 70192 / standard MHB reference specification
✓ Casein Acid Hydrolysate selected for low thymidine/thymine content
✓ Batch QC per ISO 11133:2014 — pH, growth promotion, appearance
✓ COA, TDS, SDS included with every order
✓ Australian stock — same-week dispatch, no import delays
31 Longview CT, Thomastown VIC 3074, Australia | ABN 56 676 640 467
✓ Formulated per Sigma-Aldrich 70192 / standard MHB reference specification
✓ Casein Acid Hydrolysate selected for low thymidine/thymine content
✓ Batch QC per ISO 11133:2014 — pH, growth promotion, appearance
✓ COA, TDS, SDS included with every order
✓ Australian stock — same-week dispatch, no import delays
⚠️ For laboratory, microbiological culture, and research use only. Not for food, therapeutic, veterinary, or direct human use. Autoclave all inoculated material before disposal.