Indicator Selective Medium Base - BioReagent

Cat. No.: I1528330

GRADE & PURITY BioReagent

Storage

Room temperature

Shipped In

Normal

Overview

For isolation and differentiation of Bacillus anthracis; requires addition of polymyxin B, lysozyme, and thallous acetate.

Specifications

Specifications & Purity

BioReagent

Storage

Room temperature

Shipped In

Normal

Grade

BioReagent

Product Line

biological_products

Application Protocols

Item-specific, validated protocols and performance controls are Not specified for this product; refer to CoA/Spec Sheet. The following is general, literature-based guidance for indicator selective media:

Plate method (general):

• Preparation: Reconstitute the medium at the specified g/L in purified water, sterilize by autoclaving as directed. If required, supplement aseptically with selective/indicator additives after cooling to ~45–50 °C (for agar media). Pour plates and allow to set/dry.
• Inoculation: Streak or spread appropriate dilutions of test sample or control strains. Incubate inverted plates at the temperature/atmosphere appropriate for target organisms.
• Interpretation: Observe colony growth and color/halo changes after the recommended incubation time. Record presumptive results and, where needed, confirm with secondary biochemical or molecular tests.

Broth method (general):

• Preparation: Reconstitute at specified g/L, sterilize, cool, and dispense aseptically.
• Inoculation and incubation: Inoculate with sample/strain, incubate with shaking or static conditions as appropriate.
• Readout: Monitor turbidity, color change, gas production (Durham tubes, if used), and pH as indicators of metabolic activity.

Controls and QA:

• Include positive and negative control organisms each run. Document lot numbers, preparation parameters (g/L, pH, autoclave cycle), and incubation conditions.

Biological Roles

This product is a complex culture medium base; it does not have a single molecular biological role. Instead, it provides a controlled environment enabling selective growth and phenotypic indication.

General/literature context:

• Nutritional support: Peptones/tryptones supply amino acids, peptides, and nitrogen; yeast/beef extracts deliver vitamins and cofactors; carbohydrates provide fermentable energy. Salts maintain osmotic balance.
• Selectivity mechanisms: Inhibitors (e.g., bile salts, certain dyes, antibiotics, or elevated salt) limit the growth of non-target organisms, enriching for taxa of interest. Mechanisms include membrane perturbation, enzyme inhibition, or osmotic stress.
• Indicator mechanisms: pH indicators respond to acid/base production from metabolic pathways such as glycolysis/fermentation (e.g., lactose → lactic acid), amino acid decarboxylation (alkalinization), or sulfur metabolism (H2S) where metal salts form colored precipitates.
• Phenotypic readouts: Colony color, surrounding halo/precipitate, or medium color shift provides presumptive identification at the plate level without molecular assays.

Note on specificity: The precise organisms targeted and the indicator transitions depend on the exact formulation, which is Not specified for this item; consult the CoA/Spec Sheet and validate with known control strains for your application.

Buffer Applications

This product is not a conventional buffer reagent. While many culture media incorporate buffering systems (e.g., phosphate, carbonate) to stabilize pH during microbial metabolism, the exact buffer composition and pH range for this item are Not specified; refer to CoA/Spec Sheet.

General/literature guidance:

• Prepared medium pH: Media typically target a defined pH at 25 °C after sterilization, optimized for indicator transitions and organism growth. Adjust pH only if explicitly directed by the formulation.
• Osmolarity and ionic strength: Built-in salts maintain physiological conditions; external buffers (PBS, Tris) are usually not added to culture media as they can alter selectivity and indicator performance.
• Application tip: If a protocol requires overlay or diluent buffers (e.g., top agar overlays, soft agar), prepare those components separately per standard microbiological recipes to avoid diluting the selectivity/indicator balance of the base medium.

Green Alternatives

For microbiological media, green considerations emphasize resource efficiency, waste minimization, and safer components rather than classic solvent substitution.

Opportunities (general/literature):

• Dehydrated vs. ready-to-use: Using dehydrated medium base reduces shipping mass/volume and packaging compared with pre-poured plates or bottled media, lowering transport emissions and plastic waste.
• Batch sizing: Prepare only the volume required; smaller, frequent batches minimize expired waste. Autoclave in reusable borosilicate bottles rather than disposable plastics where safe and compliant.
• Energy optimization: Consolidate autoclave loads and use validated, minimal cycles to reduce energy while ensuring sterility. Avoid over-sterilization, which also degrades medium components.
• Safer additives: Where possible, choose selective/indicator components with favorable environmental and hazard profiles (e.g., minimize use of heavy metal salts for H2S detection, or replace certain dyes with less hazardous chromogens), recognizing potential trade-offs in performance.
• Water stewardship: Employ efficient water purification and heat-recovery on sterilizers; verify water quality to avoid repeating batches.

Trade-offs (general):

• Some greener indicator or selective systems may have narrower performance windows, require different incubation conditions, or be costlier. Validate alternatives with panel strains to ensure equivalent selectivity and sensitivity before full adoption.

Pharmaceutical Uses

No therapeutic or clinical claims are made for this product. For research use only.

Formulation/industry context (general/literature):

• Microbiological quality control: Indicator/selective media bases are widely used in pharmaceutical and biomanufacturing environments for environmental monitoring, bioburden testing, and microbial limits tests (e.g., in alignment with compendial approaches such as USP <61>/<62>/<1116>, Ph. Eur., JP). The exact compendial equivalence of this item is Not specified; refer to CoA/Spec Sheet and internal validation requirements.
• Raw material control: Lots are typically qualified via growth-promotion and inhibition tests using challenge strains. End users should perform incoming QC per site SOPs.
• Process support: Useful for in-process controls, cleaning validation swabs, and finished-good testing where presumptive identification or selective recovery is desired.
• Documentation: For regulated use, maintain traceable records (CoA, SDS, lot numbers), and perform method suitability testing to confirm the medium’s compatibility with product matrices and neutralizers.

Note: BioReagent grade does not imply GMP status. Users in regulated settings must qualify the medium and suppliers per their quality systems.

Physical Properties

Item-specific properties:

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• pH (of prepared medium), concentration (g/L), color/clarity after sterilization, and gel strength (if agar is included): Not specified for this item; refer to CoA/Spec Sheet.
• Moisture content, ash, and performance criteria (growth/purity controls): Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight, formula: Not applicable to mixtures; not specified for this item.

General/literature characteristics for dehydrated microbiological media (for context only):

• Physical state: Free-flowing, hygroscopic powder or granules composed of peptides/proteins, carbohydrates, salts, and indicator dyes.
• Solubility: Designed to dissolve or disperse in purified/deionized water at a defined grams-per-liter loading (per manufacturer). Gentle heating and stirring typically aid dissolution; some components may be opalescent before/after sterilization.
• Color: Varies with indicator and selective components; color may change after autoclaving or upon pH shift during incubation (e.g., indicator transition colors).
• Density/bulk properties: Highly formulation dependent; bulk density impacts weighing and container fill but is not a specification of this listing.
• Stability: Sensitive to moisture, light (for some dyes), and prolonged elevated temperature; best practice is to keep tightly closed and protected from humidity to preserve performance (literature).

Quality and Grades

Item-specific grade:

• BioReagent (per Product Data): Suitable for research and laboratory workflows. Not intended for clinical diagnostic use or human/animal administration. For research use only.

What BioReagent implies (general guidance):

• Composition quality: Components and performance are intended to meet common laboratory expectations for microbiology and biochemical research. It does not necessarily imply pharmacopoeial or GMP traceability.
• Performance focus: For microbiological media, performance is typically demonstrated through growth-promotion, inhibition, and indicator-response tests using standard strains (e.g., ATCC). For this catalog item, specific performance criteria are Not specified; refer to CoA/Spec Sheet.
• Low contaminant expectations: Bioreagent media are ordinarily manufactured to limit inhibitory contaminants (e.g., heavy metals, peroxides) that could affect microbial growth; however, item-specific contaminant limits are Not specified for this item.
• Documentation: For lot-specific details (composition, recommended g/L, pH after preparation, QC organisms), consult the CoA/Specification Sheet and SDS.

What is not included:

• Clinical diagnostic certification, GMP compliance, and pharmacopeial monographs are not implied by the BioReagent designation unless explicitly stated. Validation for regulated environments should be performed by the end user.

Reaction and Applications

Chemical reaction applications (synthetic chemistry) are not the primary use for this product. Instead, its utility lies in microbiological selection and visual indication.

Microbiology-focused applications (general/literature):

• Selective growth: Supports the growth of target microbial groups while suppressing non-targets via selective agents (e.g., bile salts, dyes, inhibitors). Useful for environmental, food, and industrial hygiene testing, and general research microbiology.
• Indicator functionality: Incorporates pH or redox indicators that change color upon biochemical activity (e.g., carbohydrate fermentation producing acid, decarboxylation producing base, H2S production forming precipitates with iron salts). Facilitates rapid visual differentiation of colonies or broth color changes.
• Enumeration and isolation: Employed for presumptive identification, isolation of specific taxa, and colony differentiation on plates; or in broths for screening metabolic traits.
• Method development: Serves as a base for customized formulations by adding defined carbohydrates, selective supplements, or chromogenic substrates to tune selectivity and readout for particular organisms.

Practical tips (general):

• Prepare per specified g/L and sterilize by autoclaving where indicated; cool to appropriate pouring temperature to preserve indicator integrity.
• Avoid over-sterilization: Excess autoclave time may degrade sugars and indicators, increasing background or false positives.
• Validate with controls: Use positive/negative control strains to confirm selectivity and indicator performance for each lot (per laboratory QA practices).

Reaction Conditions

Conventional reaction conditions (temperature, catalysts, solvents) for small-molecule synthesis are not applicable. Instead, preparation and incubation conditions govern performance.

General/literature preparation conditions:

• Reconstitution: Dissolve the specified grams per liter of dehydrated medium in purified water with gentle heat and stirring until fully dispersed. Exact g/L for this item is Not specified; refer to CoA/Spec Sheet.
• Sterilization: Autoclave at 121 °C for 15 minutes (typical), unless the formulation specifies otherwise. Avoid excessive autoclave times that can degrade sugars and indicators.
• Additives: Aseptically add heat-labile selective supplements or antibiotics after cooling to ~45–50 °C for agar media, or to room temperature for broths.
• Pouring plates: For agar-containing media, pour into sterile Petri dishes at ~45–50 °C to minimize condensation and preserve indicator integrity. Allow to solidify and dry to desired surface moisture before use.
• Incubation: Temperature and atmosphere depend on target organisms (e.g., 30–37 °C for many bacteria; aerobic/anaerobic as needed). Specific conditions for this item are Not specified.

Quality checks:

• Include positive/negative control strains to confirm selectivity, growth promotion, and indicator color response for each lot.
• Record pH before/after sterilization if specified by the method; large deviations can signal preparation issues.

Safety and Handling

Item-specific hazard classifications (GHS) and statements:

• Signal word, H-statements, pictograms, and GHS classification: Not specified for this item; refer to SDS.

General safety guidance for dehydrated culture media (literature/good practice):

• Likely hazards: Dust may cause mechanical irritation to eyes/respiratory tract; indicator dyes and selective agents may present irritant or harmful hazards. Avoid inhalation of dusts and contact with skin/eyes.
• PPE: Use lab coat, safety glasses or face shield, and disposable nitrile gloves. Consider a dust mask/respirator if handling large quantities or if dusting occurs (per institutional risk assessment).
• Handling: Work in a clean area to prevent microbial contamination of the medium. Avoid cross-contamination between selective/indicator media. Use clean, dry tools; reseal containers promptly to minimize moisture uptake.
• Incompatibilities: Strong oxidizers/reducers may degrade indicator dyes; moisture and light can reduce shelf-life. Store away from volatile amines/acids that could shift pH.
• First aid (overview; defer to SDS): If inhaled, move to fresh air; if on skin/eyes, rinse with water for several minutes; if ingested, rinse mouth. Seek medical attention if symptoms persist.
• Biosafety note: Once reconstituted and inoculated with microorganisms, treat plates/broths as biohazardous. Follow appropriate containment, sterilization (autoclave), and disposal procedures according to institutional biosafety guidelines.

Solvent Selection

This product is a dehydrated culture medium base intended for reconstitution in water; organic solvent selection is not typically applicable.

Practical guidance (general/literature):

• Water quality: Use freshly produced deionized or distilled water meeting microbiological media preparation standards (e.g., ASTM Type II or better) to avoid inhibitory ions or residual disinfectants (chloramines) that can affect growth and indicator response.
• pH control: Media often have a target pH at 25 °C after sterilization; adjust only if the manufacturer specifies. Buffering (e.g., phosphates) is usually built-in; excessive adjustment may impair selectivity/indicator performance.
• Additives: Heat-labile selective supplements (e.g., certain antibiotics) should be dissolved in sterile water or appropriate sterile aqueous stocks and added aseptically after autoclaving and cooling to ~45–50 °C (for agar media) or room temperature (for broths).

Comparison note (literature):

• Rehydration medium: Purified water is preferred. Saline (0.85%) or PBS is usually not used to prepare the base itself unless a formulation specifically requires ionic strength adjustment, as these can alter osmolarity and selectivity.
• Alternatives: Ready-to-use bottled media or pre-poured plates remove the solvent preparation step but reduce flexibility and may increase cost and packaging waste.

Storage and Reconstitution

Item-specific storage and shipping:

• Storage conditions: Room temperature (per Product Data). Protect from moisture and light; keep container tightly closed.
• Shipped in: Normal (per Product Data).

General reconstitution guidance (literature; follow CoA/Spec Sheet for exact parameters):

• Weigh the specified grams of dehydrated medium per liter of purified/deionized water (exact g/L Not specified for this item). Disperse with stirring; gentle heating aids dissolution. Avoid overheating or caramelization of sugars.
• Adjust pH only if directed by the formulation; verify pH at 25 °C. Many media specify pH after sterilization.
• Sterilize by autoclaving at 121 °C for 15 minutes unless otherwise noted. Do not over-sterilize; prolonged heating degrades indicators and carbohydrates.
• For agar media: Cool to ~45–50 °C before pouring plates. Add heat-labile supplements aseptically after cooling but before solidification. For broths: Cool to room temperature and dispense aseptically.

Shelf-life and handling:

• Unopened shelf-life follows manufacturer dating; lot-specific expiry Not specified for this item—refer to label/CoA. Once opened, minimize exposure to air and humidity; consider desiccant storage.
• Prepared media are best used within recommended windows (e.g., days to weeks depending on formulation and storage); store plates at 2–8 °C protected from light when applicable. Discard if contamination, drying, or indicator color drift is observed.

Structure and Identity

Item-specific identity details for this catalog listing reflect a complex dehydrated culture medium base rather than a single defined chemical entity.

• Product name: Indicator Selective Medium Base (SKU: I1528330)
• Category path: 全部 / 可售 / 生命科学
• CAS, CID, InChIKey, SMILES: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular formula and molecular weight: Not specified for this item; refer to CoA/Spec Sheet.
• Grade: BioReagent (per Product Data)

General/literature description (mixture-level):

• Composition type: Dehydrated microbiological medium base typically comprising peptones/tryptones (nitrogen/amino acids), yeast/beef extracts (vitamins, growth factors), salts and buffering components, fermentable carbohydrates, and one or more indicator dyes (e.g., neutral red, bromothymol blue, phenol red) plus selective agents (e.g., bile salts, deoxycholate, or inhibitory compounds). Exact components and concentrations vary by formulation and are not specified for this item.
• Structural features: As a mixture, it lacks a single 2D/3D structure. Individual constituents may include aromatic sulfonated dyes, saccharides, amino acid fragments/peptides, and inorganic salts. Indicator components are typically pH- or redox-responsive chromophores that undergo protonation-state or redox-state changes, causing visible color shifts around characteristic transition ranges (literature).
• Function-defining identity: “Selective” denotes suppression of non-target organisms; “Indicator” denotes visual readout of a biochemical trait (e.g., carbohydrate fermentation, lactose utilization, H2S formation) via color change or precipitate (literature).

Synthetic Utility

This product is not a building block or reagent for chemical synthesis. It is a complex mixture formulated for microbiological cultivation with selectivity and indicator functionality.

General/literature perspective for laboratory workflows:

• Not used in organic synthesis, catalysis, or polymerization.
• May serve as a biological test matrix for assessing antimicrobial performance, sanitizer residuals, or metabolic activity of engineered strains.
• Some constituents (e.g., peptides, sugars, salts) can interfere with chemical assays; if interfacing with analytical chemistry workflows (HPLC/LC–MS), consider sample cleanup (filtration, SPE, protein precipitation) prior to analysis.

For synthetic chemists collaborating with microbiologists, coordinate on medium composition and indicator chemistry if optical readouts (UV–vis/fluorescence) are part of assay endpoints, as dye absorbance peaks and pH transitions can overlap with analyte detection. Exact indicator identities and spectra for this item are Not specified; consult CoA/Spec Sheet.

Target Specificity

Antibody/biomolecule targeting details (antigen, clone, epitope, isotype, species reactivity) are not applicable to this product.

Microbiological specificity (general/literature):

• Indicator selective media are designed to favor growth of selected microbial groups and provide phenotypic readouts. The exact target organisms, inhibitors, and indicator chemistries for this item are Not specified; refer to CoA/Spec Sheet and validate with appropriate control strains relevant to your application.