E. coli O157 Chromogenic Medium - BioReagent

Cat. No.: E1528747

GRADE & PURITY BioReagent

Storage

Store at 2-8°C

Shipped In

Wet ice

개요

For rapid detection of O157 bacteria; O157 colonies appear red

Specifications

사양 및 순도

BioReagent

보관 조건

Store at 2-8°C

배송

Wet ice

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등급

BioReagent

Product Line

생물 제품

Application Protocols

The Product Data do not include a protocol for this SKU. The following is general, literature-based guidance for chromogenic media and should be adapted to your SOPs. For item-specific instructions (e.g., grams per liter, autoclave cycle, supplement handling), refer to the CoA/Spec Sheet.

General workflow (plates):

• Reconstitution and sterilization: Dissolve the specified mass of dehydrated medium in purified water. Sterilize as directed (often autoclave). If heat-labile chromogens/selectives are provided separately, cool base to ~45–55°C and aseptically add supplements; pour plates and allow to set/dry.
• Sample processing: Plate test samples directly or after enrichment according to your method. Avoid overloading plates; aim for well-isolated colonies.
• Incubation: 35–37°C for 18–24 h (typical, literature). Read colony colors on a dry surface under white light; avoid strong colored backgrounds.
• Quality controls: Include positive/negative controls with each batch.
• Follow-up: Perform confirmatory identification (e.g., serogrouping, molecular assays) for presumptive colonies as required.

Troubleshooting (general):

• Weak/ambiguous colors: Verify supplement integrity, avoid overheating, ensure correct pH, and control plate moisture.
• Overgrowth by background flora: Confirm selective agent potency and sample dilution; check incubation temperature.
• No growth of controls: Reassess sterilization parameters, supplement addition steps, and storage conditions.

Biological Roles

This section provides biological context for the target organism and detection principle (general literature; not item-specific specifications).

• E. coli O157 background: A serogroup within Escherichia coli distinguished by its O157 somatic antigen. Many O157:H7 strains are β-D-glucuronidase negative and sorbitol non-fermenting, phenotypes frequently leveraged for differential culture.
• Chromogenic principle: Chromogenic media include substrates consisting of a sugar or peptide linked to a chromophore. Organism-specific enzymes cleave these substrates, releasing an insoluble colored product localized to colonies. For E. coli differentiation, substrates targeting β-D-galactosidase and/or β-D-glucuronidase are commonly used, with E. coli O157 typically showing distinct coloration due to lack of glucuronidase activity.
• Selective ecology: Bile salts, dyes, or other inhibitors are often used to reduce growth of Gram-positives and certain Gram-negatives, enriching for enteric bacteria such as E. coli (literature/general).
• Research applications:
  • Food and water microbiology method development, challenge studies, and training.
  • Environmental persistence and survival studies for E. coli in varied matrices.
  • Evaluation of enrichment strategies and confirmation workflows.

Note: No clinical/diagnostic use is claimed or implied. For research use only (per Product Data). Exact chromogens, inhibitors, and performance claims for SKU E1528747 are not specified; refer to CoA/Spec Sheet.

Buffer Applications

This product is a complete/selective culture medium, not a standalone buffer system. Therefore, classical buffer recipes (e.g., HEPES, Tris) are not applicable.

General medium buffering considerations (literature; not item-specific):

• Many enteric media are buffered near neutral pH using phosphate or organic buffers to maintain colorimetric and growth performance during incubation.
• If preparing from a dehydrated base, confirm the final pH after sterilization and cooling, as autoclaving can shift pH; adjust only if instructed by the product’s preparation guide.
• Use calibrated pH meters at the temperature of measurement; avoid CO2 absorption during cooling, which can slightly acidify the medium.

For exact buffer capacity, pH targets, and adjustment instructions for SKU E1528747: Not specified for this item; refer to CoA/Spec Sheet.

Green Alternatives

While this product category is not a reaction solvent or reagent prone to significant environmental emissions, sustainability considerations still apply to microbiological media use.

Green chemistry/microbiology considerations (general):

• Energy use: Optimize autoclave loads and cycles; use validated minimal sterilization times to reduce energy consumption while maintaining sterility assurance.
• Waste minimization: Pour only the number of plates required; use smaller plate formats or compartmental plates when appropriate to reduce plastic and medium consumption.
• Safer components: Where feasible, prefer formulations that avoid heavy-metal-based inhibitors or high-toxicity antibiotics. Specific inhibitor profile for this SKU is not specified; refer to CoA/Spec Sheet.
• Water stewardship: Prepare media with high-purity water to minimize batch failures and rework; collect and cool autoclave effluent responsibly.
• Packaging: Consolidate orders to reduce shipping materials; recycle cardboard and use plate sleeves with recyclable content when available.

Comparison (general, illustrative):

• Traditional indicator systems (e.g., bile salts plus carbohydrate fermentation) versus chromogenic substrates:
  • Chromogenic media can reduce confirmatory testing time (fewer subcultures), potentially lowering resource use.
  • Tradeoff: Chromogenic substrates may be more specialized and sensitive to heat/light, requiring careful handling to avoid waste.

Note: Specific environmental attributes or ecolabels for SKU E1528747 are not specified; consult the product documentation for any available sustainability statements.

Pharmaceutical Uses

This product is not a therapeutic agent. It may be applicable in pharmaceutical and biomanufacturing quality laboratories for research, method development, and non-clinical QC workflows involving microbial monitoring (research use only).

General, literature-based context (not item-specific claims):

• Environmental monitoring and hygiene studies: Chromogenic media can facilitate rapid differentiation of presumptive E. coli colonies in facility assessments and water system evaluations.
• Raw material/water testing method development: Useful for selecting culture-based steps prior to confirmatory identification (e.g., biochemical or molecular assays conducted separately).
• Training and validation: Supports analyst training and internal method suitability studies where differentiation of E. coli phenotypes is needed.

Regulatory note:

• No pharmacopeial monograph or clinical diagnostic clearance is indicated in the Product Data. Use according to applicable internal SOPs and validation protocols. For specific compendial requirements (e.g., USP/EP/JP) or alternative culture media mandates, consult those standards directly.

Physical Properties

Item-specific physico-chemical specifications are not provided in the Product Data for this formulated medium.

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• pH (prepared medium): Not specified for this item; refer to CoA/Spec Sheet. (Typical E. coli-selective chromogenic media are buffered near neutral pH, literature/general.)
• Solubility: Intended for dissolution/suspension in purified water for medium preparation (general practice, literature). Specific solubility and clarity endpoints: Not specified for this item; refer to CoA/Spec Sheet.
• Color of dehydrated base and of prepared medium: Not specified for this item; refer to CoA/Spec Sheet.
• Sterility: Prepared medium should be sterilized as directed in product insert (e.g., autoclave or sterile filtration for heat-labile components). Exact conditions: Not specified for this item; refer to CoA/Spec Sheet.
• Physical state: Typically supplied as a dehydrated powder or ready-to-use plates/bottled medium (category-general). Specific form for this SKU: Not specified for this item; refer to CoA/Spec Sheet.

General literature notes (not item specifications):

• Many chromogenic media incorporate heat-labile substrates added after autoclaving when cooled to ~45–55°C to preserve color performance.
• Medium gelation (if agar-based) depends on agar concentration (~1.5% w/v typical for plates, literature). This SKU’s agar content/format is not specified; refer to CoA/Spec Sheet.

Quality and Grades

• Grade/Purity: BioReagent (per Product Data).

What BioReagent typically implies (general industry context):

• Suitable for research and laboratory microbiology applications requiring consistent performance and low extraneous contaminants that could interfere with microbial growth or chromogenic reactions.
• Does not imply clinical diagnostic certification or pharmacopeial compliance. This product is labeled For research use only (per Product Data).

Quality considerations for chromogenic media (general/literature):

• Lot-to-lot consistency of selective agents and chromogenic substrates is critical for reliable colony coloration and selectivity.
• Low background color and low autoclave-induced darkening help ensure high contrast of target colonies.
• QC may include performance testing with reference strains (e.g., E. coli O157-positive/negative controls and common background flora). Specific QC panels for this SKU: Not specified for this item; refer to CoA/Spec Sheet.

Item-specific notes:

• Stabilizers, antibiotic contents, UV cutoff, metal limits, and detailed specifications: Not specified for this item; refer to CoA/Spec Sheet.
• Documentation: For exact formulation, preparation instructions, and performance criteria, consult the product label, certificate of analysis, and specification sheet for SKU E1528747.

Reaction and Applications

This chromogenic medium is formulated for selective/differential culture of Escherichia coli O157 in research, food/environmental microbiology, and method development settings (research use only).

General application concepts (literature, not item-specific):

• Differential readout: Incorporates chromogenic substrates that yield colored colonies upon cleavage by specific bacterial enzymes. E. coli O157 typically lacks β-D-glucuronidase activity and often exhibits distinct chromogenic profiles compared to non-O157 E. coli.
• Selectivity: Inhibitory components suppress competing flora while permitting growth of target E. coli. Background organisms may yield different colors or be inhibited.
• Workflows:
  • Direct plating of test samples or enrichment cultures onto prepared plates.
  • Incubation at 35–37°C for 18–24 h (typical range; literature) with observation of colony color/morphology.
  • Optional confirmation: latex agglutination for O157 antigen, PCR, or biochemical tests (performed separately; not included in this product).
• Practical tips:
  • Use appropriate positive/negative control strains in each batch to verify color development and selectivity.
  • Avoid overheating heat-labile chromogens; if the formulation separates these, add them post-sterilization at recommended temperatures (literature practice).
  • Plate surface moisture control is key; excessive condensation can lead to color diffusion and ambiguous colony edges.
• Related media (context): Sorbitol-MacConkey (SMAC) and other chromogenic O157 media are commonly used as complementary or confirmatory tools; selection depends on sample matrix and regulatory method guidance (literature).

Reaction Conditions

Classical chemical reaction conditions are not applicable. However, culture/incubation conditions determine performance in microbiology workflows (general, literature guidance; not item-specific specifications):

• Inoculation: Streak or spread sample/enrichment onto dry plate surface to achieve isolated colonies.
• Incubation temperature: Commonly 35–37°C for enteric bacteria. Exact temperature/time for SKU E1528747: Not specified for this item; refer to CoA/Spec Sheet.
• Incubation time: Typical first read at 18–24 h; some samples may benefit from a 24–48 h second read (literature/general).
• Atmosphere: Ambient aerobic conditions are standard unless otherwise directed by the method.
• Interpretation: Assess colony color, morphology, and surrounding medium reactions. Record presumptive positives and proceed to confirmatory tests (e.g., serology, PCR) as required by your SOP.
• Controls: Include positive control (E. coli O157 reference strain) and negative control (non-O157 E. coli and/or background flora) to verify selectivity and chromogenic differentiation each batch.

Note: Exact preparation parameters (e.g., grams per liter, autoclave cycle, and any post-autoclave supplement additions) for this SKU are not specified here; refer to the product label and CoA/Spec Sheet.

Safety and Handling

GHS and hazard classifications are not provided in the Product Data for this item. Always consult the product-specific SDS for authoritative guidance.

• Signal word / H-statements / Pictograms: Not specified for this item; refer to SDS.
• Primary hazards (general for microbiological media):
  • Dehydrated media can cause dust irritation to eyes/respiratory tract; avoid inhalation and contact.
  • Chromogenic substrates and selective agents may be irritants or sensitizers (literature/general). Handle with gloves and eye protection.
  • Once inoculated, plates/broths are biohazardous; handle per BSL-appropriate procedures and local regulations.
• Recommended PPE and engineering controls:
  • Lab coat, nitrile gloves, safety glasses or face shield; handle powders in a fume hood or with local exhaust to minimize dust.
  • Use biological safety cabinet (Class II) for manipulations of live cultures as appropriate to organism risk group.
• Incompatibilities and storage precautions:
  • Store at 2–8°C (per Product Data). Protect from moisture and microbial contamination. Keep container tightly closed.
  • Avoid excessive heat and light; some chromogens and antibiotics degrade upon prolonged exposure (general literature guidance).
• First-aid (general):
  • Inhalation: Move to fresh air; seek medical attention if symptoms persist.
  • Skin/eye contact: Rinse with water for several minutes; remove contaminated clothing; seek medical advice if irritation continues.
  • Ingestion: Rinse mouth; do not induce vomiting; obtain medical attention.
• Waste: Autoclave or disinfect inoculated materials before disposal; follow institutional biosafety policies.

Solvent Selection

This product is not a reaction solvent; it is a culture medium. Solvent selection per se is not applicable. However, water quality used for medium preparation strongly affects performance.

• Recommended solvent for reconstitution: Purified water (e.g., ASTM Type 1/2 DI or equivalent). Exact volume and concentration: Not specified for this item; refer to CoA/Spec Sheet.
• Considerations (general, literature):
  • Avoid high levels of chlorine, heavy metals, or organics that can inhibit microbial growth or alter chromogenic responses.
  • For heat-labile components, dissolve separately in sterile water and aseptically add to cooled, sterilized base medium.
  • If preparing plates: ensure proper agar hydration and avoid air bubbles for even surface; dry plates to remove excess surface moisture prior to use.
• Comparison to alternatives:
  • Tap water can introduce variable ions and inhibitors—use only if validated for your lab’s microbiology workflows.
  • Sterile-filtered vs autoclaved water: Use per component stability; chromogens/antibiotics are often sterilized by filtration (literature/general).

Storage and Reconstitution

• Storage conditions: Store at 2–8°C (per Product Data). Keep container tightly closed. Protect from moisture, heat, and light. Shipped on wet ice (per Product Data) to maintain stability.
• Shelf life/expiry: Not specified for this item; refer to CoA/Spec Sheet and product label.
• Reconstitution/preparation: Exact grams per liter, sterilization cycle, and any supplement additions are not specified for this item; refer to CoA/Spec Sheet. General practice (literature): dissolve in purified water, adjust as directed, sterilize, and if applicable add heat-labile components aseptically after cooling.
• Plate storage (if applicable): Store prepared plates inverted in sealed sleeves at 2–8°C; allow plates to equilibrate to room temperature and dry surface condensation before inoculation. Specific hold times: Not specified for this item; refer to CoA/Spec Sheet.
• Freeze–thaw: Not applicable to dehydrated media; avoid freezing prepared plates unless explicitly validated, as freeze–thaw can crack agar and degrade chromogens (general guidance).
• Handling after opening: Minimize exposure to ambient humidity; desiccant packs and rapid resealing help prevent caking and loss of performance. Label with open date and track lot/expiry in your documentation.

Always defer to the product’s label, SDS, and CoA/Spec Sheet for definitive storage and preparation instructions for SKU E1528747.

Structure and Identity

This product is a prepared/dehydrated microbiological medium formulated for the selective and differential detection of Escherichia coli O157 using chromogenic substrates.

• SKU: E1528747
• Product name: E. coli O157 Chromogenic Medium
• Item type: Complex mixture (microbiological growth medium with selective/differential components)
• Grade: BioReagent (per Product Data)
• Molecular formula: Not applicable (mixture). Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight: Not applicable (mixture). Not specified for this item; refer to CoA/Spec Sheet.
• SMILES / InChIKey / CAS / CID: Not applicable to mixtures. Not specified for this item; refer to CoA/Spec Sheet.

Structural features (general, literature):

• Typical E. coli O157 chromogenic media incorporate:
  • A nutrient base (peptones/yeast extract) and buffering salts.
  • Selective inhibitors to suppress competing Gram-positive/Gram-negative flora (e.g., bile salts or other agents; literature/general info).
  • One or more chromogenic substrates that report on enzymatic activities relevant to E. coli identification (e.g., β-D-glucuronidase-negative phenotype typical of O157:H7 vs other E. coli; literature/general info).
  • Carbohydrate(s) for differential fermentation patterns (e.g., sorbitol in related formulations; literature/general info).

2D “structure” description in words:

• As a formulated mixture, there is no single molecular structure; rather, the medium consists of a heterogeneous blend of organic nutrients, salts, and chromogenic indicator(s) designed to yield organism-specific colony colors upon enzyme-mediated cleavage of chromophores (general, literature).

Synthetic Utility

Not applicable. This product is a microbiological growth medium and is not used as a reagent or building block in chemical synthesis.

If your project involves synthesis of chromogenic substrates or indicators related to medium design, consult specialized synthetic literature on glycosidic or peptidic chromophores (general note). For practical guidance relevant to this product, see Reaction & Applications and Application Protocols.

Target Specificity

Target specificity fields (antigen/epitope/clone/isotype/species) do not apply to culture media. This product is not an antibody or affinity reagent. Selectivity toward E. coli O157 is addressed conceptually under Reaction & Applications, but no item-specific performance claims are provided in the Product Data; refer to CoA/Spec Sheet for validated performance characteristics, if available.