Soybean-Casein Digest Agar Medium (USP) - BioReagent

Cat. No.: S1528405

GRADE & PURITY BioReagent

Storage

Room temperature

Shipped In

Normal

Übersicht

For total bacterial count determination. Preparation method: Weigh 40.0 g of this product in 1 L of distilled or deionized water, heat to boiling until completely dissolved, dispense, autoclave at 121°C for 15 minutes. After sterilization, shake well to prevent agar from settling and solidifying at the bottom of the vessel, then set aside for use.

Specifications

Spezifikationen & Reinheit

BioReagent

Storage

Room temperature

Verschickt in

Normal

Note

BioReagent

Application Protocols

The following are general, literature‑based protocols for preparing and using Soybean‑Casein Digest Agar. Adjust per your SOPs and the product’s label/CoA.

A. Preparation of TSA plates (typical):

1. Weigh ~40 g medium per liter of purified water into a heat‑resistant flask.
2. Add powder gradually with stirring; heat to dissolve completely (near boiling).
3. Autoclave at 121 °C for 15 minutes.
4. Cool to 45–50 °C in a water bath; if needed, aseptically add supplements (e.g., neutralizers, blood).
5. Pour 20–25 mL per 90‑mm Petri dish; allow to solidify. Dry plates as needed to remove surface moisture. Store inverted at 2–8 °C or per SOP; warm to room temperature before use.

B. Spread plate enumeration:

1. Prepare serial dilutions of the sample in appropriate diluent.
2. Pipette 0.1 mL onto the surface of a pre‑dried plate; spread with a sterile spreader to dryness.
3. Invert and incubate at 30–35 °C for 48–72 h (or per method).
4. Count plates with 30–300 colonies; calculate CFU per gram/mL.

C. Pour plate method:

1. Pipette 1.0 mL sample into sterile Petri dish.
2. Add ~15–20 mL molten (45–50 °C) TSA; mix gently; allow to solidify.
3. Invert and incubate as specified; count colonies (surface and subsurface).

D. Environmental monitoring (surface contact): Use contact plates or swabs with neutralizers as specified by SOPs; incubate under defined conditions and trend CFU results.

Always include positive/negative controls and perform growth promotion testing for qualified lots.

Biological Roles

This product does not have a singular biological role as a molecule; rather, it functions as a nutrient matrix that supports microbial growth.

Functional components (literature/general):

• Peptones (casein and soybean digests): Supply peptides, free amino acids, and growth factors. Soy digest contributes vitamins and carbohydrates remnants; casein digest is rich in peptides favorable to many heterotrophs.
• Sodium chloride: Maintains osmotic balance compatible with many non‑halophilic bacteria.
• Agar: Provides a non‑nutritive, solid support for colony isolation and morphology assessment.

Microbiological performance:

• Broad-spectrum support for aerobic and facultative anaerobic bacteria, including many environmental and QC test organisms.
• Suitable for recovery of sublethally stressed cells after processing or disinfectant exposure when used without selective inhibitors.

pH environment (literature): Neutral pH (~7.3) approximates many bacteria’s optimal growth range, aiding broad recovery.

Limitations:

• Not optimized for fastidious organisms (e.g., certain streptococci, H. influenzae) without enrichment (e.g., blood, NAD, hemin).
• Not selective; background flora may overgrow target organisms in heavily contaminated samples—use selective/differential media where required.

Use domain: For research and laboratory quality control use only (per Product Data). Not for human or animal consumption or therapeutic use.

Buffer Applications

This product is not a dedicated buffering reagent. Although prepared Soybean‑Casein Digest Agar exhibits a near‑neutral pH (literature: ~7.3 after sterilization), it is intended as a nutrient medium rather than as a defined chemical buffer.

• If a defined buffer is required (e.g., for enzyme assays or pH‑controlled reactions), select an appropriate buffering system (phosphate, Tris, HEPES) with known concentration and pKa values.
• Within microbiology workflows, pH is set by the medium formulation and autoclave conditions and is verified as part of quality control rather than adjusted dynamically like a buffer.

For buffer recipes and applications unrelated to culture media, refer to dedicated buffering agents and validated protocols.

Green Alternatives

While culture media selection is driven by microbiological performance and compendial suitability, several sustainability considerations can reduce environmental impact without compromising results.

Greener practice options (general):

• Use dehydrated media (this product) rather than pre‑poured plates when feasible to minimize packaging waste and shipping mass; pour plates as needed to reduce expired plate disposal.
• Optimize batch sizes to limit overproduction and autoclave cycles, reducing energy and water use.
• Employ efficient autoclaves with heat recovery and validated shorter cycles where method‑appropriate.
• Prefer reusable glassware (Durham tubes, flasks, bottles) over single‑use plastics when biosafety and QA allow.
• Source agar from sustainably managed seaweed suppliers where available; many manufacturers participate in responsible supply chains.

Comparison (literature-based, general):

• Soybean‑Casein Digest Agar (TSA) versus selective/differential agars:
  • TSA is non‑selective and broadly supportive; avoiding unnecessary selective agents reduces chemical footprints (e.g., no bile salts/dyes/antibiotics).
  • Where selectivity is required, choose the least toxic/selective additives compatible with your target organisms and validation.
• Ready‑to‑use plates vs. in‑house pouring:
  • Ready‑to‑use: Saves labor and sterilization energy on site but increases packaging and cold‑chain in some cases.
  • In‑house: Higher energy for autoclaving but reduced transport footprint and flexible batch sizing.

Note: Any process modification must maintain compliance with validated methods (e.g., USP/EP/JP). Document changes through your quality system.

Pharmaceutical Uses

Context: The following describes typical roles of Soybean‑Casein Digest Agar in pharmaceutical quality control and compendial microbiology. It does not imply any clinical/therapeutic use.

• Compendial role (general literature): TSA (Soybean‑Casein Digest Agar) is widely referenced in pharmacopeial methods (e.g., USP/EP/JP) as a non‑selective medium for microbial enumeration tests, environmental monitoring, and recovery of test strains used in growth promotion testing.
• Environmental monitoring: Used in cleanrooms for surface and air monitoring (settle plates, contact plates) to track facility bioburden. Plates may be supplemented with neutralizers (e.g., lecithin, polysorbate 80) when monitoring disinfected surfaces per SOPs.
• Microbiological examination of non‑sterile products: Employed in total aerobic microbial count (TAMC) by plate count methods alongside selective media for yeasts/molds where required.
• Sterility testing workflows: As a general recovery agar for verifying culture purity/viability of isolates grown from sterility test broths, where appropriate.
• Validation and GPT: Each lot/medium batch is typically subjected to growth promotion, inhibition, and indicatory properties tests using pharmacopeial challenge organisms.

Regulatory note: Where “USP” alignment is required, confirm lot-specific conformity, GPT results, and pH specifications on the CoA/Spec Sheet for this SKU (S1528405). Maintain documentation within your pharmaceutical quality system.

Physical Properties

This product is a dehydrated, blended microbiological medium. As a complex mixture, single-compound physicochemical constants are not applicable.

• Appearance: Not specified for this item; refer to CoA/Spec Sheet. (Literature: typically a beige to light tan, free‑flowing powder.)
• Odor: Not specified for this item; refer to SDS. (Literature: mild peptone-like.)
• Solubility (literature): Disperses and dissolves in purified water with heating; agar component requires heating to near boiling to fully melt. Forms a firm gel upon cooling (typically ~1.5% agar).
• pH of prepared medium (literature): ~7.3 ± 0.2 at 25 °C after sterilization (per common TSA/USP monographs).
• Gel strength (literature): Suitable for plate pouring at ~15 g/L agar; solidifies around 35–40 °C; melts >80–85 °C.
• Density/bulk density: Not specified for this item; refer to CoA/Spec Sheet.
• Refractive index, logP, pKa, BP/MP: Not applicable to this heterogeneous mixture; agar exhibits melting/gelation behavior rather than a discrete melting point.

Practical handling properties (general):

• Hygroscopicity: Peptones can absorb moisture; keep container tightly closed to prevent caking and pH drift.
• Suspensibility: Wet powder with a portion of cold water to avoid clumping; complete dissolution upon heating with stirring before sterilization.

All numeric values above, where given, are typical literature characteristics for Soybean‑Casein Digest Agar preparations and are provided for general guidance only. Always confirm item‑specific specifications on the CoA/Spec Sheet.

Quality and Grades

• Item-specific grade: BioReagent (per Product Data). BioReagent typically indicates suitability for biological research applications, including microbiological culture work, with controlled bioburden and performance characteristics appropriate for lab use. It is not necessarily equivalent to clinical/diagnostic grade.
• USP designation in name: “Soybean‑Casein Digest Agar (USP)” aligns with pharmacopeial media used in compendial tests (e.g., USP <61>/<62> for microbiological examination of non‑sterile products, USP <71> contexts where specified). This naming indicates intended formulation/use class; item‑specific compliance and QC results (growth promotion testing, pH, sterility) should be confirmed on the CoA.
• Performance attributes to verify on CoA/Spec Sheet (not specified here):
  • pH of prepared medium (typically ~7.3 at 25 °C; literature)
  • Growth promotion testing (GPT) with challenge strains
  • Sterility/bioburden of dehydrated lot
  • Gel clarity and firmness, moisture content, and fill weight uniformity if preportioned
• Stabilizers/preservatives: Not specified for this item; refer to CoA/Spec Sheet. Dehydrated media generally contain no preservatives; sterility is achieved post‑preparation by autoclaving/filtration.
• Trace contaminants/UV cutoff/metal limits: Not specified for this item; refer to CoA/Spec Sheet.
• Practical implications:
  • Choose BioReagent/USP‑named media when reproducibility and compatibility with compendial QC methods are required.
  • For regulated testing, retain lot CoA and GPT results with your batch records.

Storage condition per Product Data: Room temperature; protect from moisture. Shipping: Normal conditions.

Reaction and Applications

Chemical reaction chemistry is not the focus here. Instead, this medium is used for cultivation and enumeration of microorganisms.

Key laboratory applications (literature/general):

• General-purpose growth medium for a wide range of aerobic and facultative anaerobic bacteria from clinical, environmental, food, cosmetic, and pharmaceutical samples.
• Compendial/industrial microbiology: Commonly used in procedures aligned with USP/EP/JP for microbiological examination of non‑sterile products (e.g., plate count methods), environmental monitoring, and utility testing.
• Environmental monitoring: Surface contact plates or pour/spread plates for cleanroom monitoring; can be supplemented with neutralizers (e.g., lecithin/Tween) when required by protocols.
• Sterility and bioburden assessments: As a non‑selective agar for recovery of stressed organisms following validation or sanitation studies.

Rationale for performance:

• Casein and soybean digests provide a broad spectrum of peptides, amino acids, and growth factors.
• Sodium chloride maintains osmotic balance.
• Agar supplies a firm surface for colony formation.

Practical tips:

• Perform growth promotion testing (GPT) on each lot with relevant challenge strains (e.g., S. aureus, P. aeruginosa, B. subtilis, E. coli, C. albicans—organisms per compendia; selection depends on method).
• For heat‑sensitive supplements (e.g., blood, antibiotics), cool sterilized medium to 45–50 °C before aseptic addition.
• Avoid overheating/over‑autoclaving, which can cause caramelization/peptone Maillard reactions and darkening, potentially inhibiting some organisms.

Reaction Conditions

This section provides typical preparation and incubation conditions for Soybean‑Casein Digest Agar based on literature/compendial practices. Values are general guidance only; verify the label/CoA for this item (S1528405).

Preparation (literature typical):

• Concentration: ~40 g dehydrated medium per liter of purified water (yields ~1.5% agar). Follow item label if it differs.
• Dispersion: Add powder gradually to water with vigorous stirring.
• Dissolution: Heat with frequent agitation to bring to near boiling until the medium is completely dissolved.
• pH: Typically ~7.3 ± 0.2 at 25 °C after sterilization.
• Sterilization: Autoclave at 121 °C for 15 minutes.
• Plate pouring: Cool to 45–50 °C; pour aseptically into sterile Petri dishes; allow to solidify. Store plates inverted to prevent condensation.

Incubation (general examples; adjust per method):

• Aerobic heterotrophs (TAMC contexts): 30–35 °C for 48–72 h.
• Environmental monitoring: 30–35 °C (bacteria) or 20–25 °C for broader flora recovery; durations per SOP.
• Growth promotion testing: Incubate compendial challenge strains at temperatures specified in the relevant chapter until characteristic growth is observed.

Quality checks:

• Visual clarity and color of prepared medium; absence of precipitate.
• pH verification at 25 °C.
• Sterility check (uninoculated control plates) per lot/batch.

Avoid prolonged overheating/autoclaving beyond recommended parameters to prevent sugar/protein degradation and color darkening, which may reduce recovery of some organisms.

Safety and Handling

• GHS classification, signal word, pictograms, H‑statements: Not specified for this item; refer to the SDS for authoritative safety information.
• General hazard profile (literature/good practice): Dehydrated microbiological media are generally regarded as laboratory reagents of low acute toxicity. However, dust can be irritating to the respiratory tract, eyes, and skin. Contains protein hydrolysates from soy and casein—avoid inhalation and contact, especially for individuals with known allergies to soy/dairy proteins.
• Biohazard considerations: The unused medium is not biohazardous. After inoculation, plates/broths may contain viable microorganisms and must be handled as biohazardous waste. Decontaminate by autoclaving (e.g., 121 °C for ≥15–30 min) before disposal according to local regulations.
• Incompatibilities: Avoid strong oxidizers and moisture uptake. Keep away from sources of microbial contamination until sterilized/prepared.
• PPE recommendations (good lab practice): Lab coat, safety glasses, and appropriate gloves. Use a dust mask or respirator if generating airborne dusts. Employ biological safety cabinets (BSC) when handling pathogenic strains as dictated by your biosafety level (BSL) protocols.
• First aid (overview; consult SDS):
  • Inhalation: Move to fresh air; seek medical attention if irritation persists.
  • Skin/eye contact: Rinse with water; remove contaminated clothing; seek medical advice if irritation continues.
  • Ingestion: Rinse mouth; obtain medical advice if unwell.
• Fire safety: Organic content may burn; use water spray, CO2, foam, or dry chemical as appropriate. Thermal decomposition may produce CO/CO2.

Always defer to the product’s SDS and your institution’s biosafety procedures for definitive guidance.

Solvent Selection

Not a solvent. This product is a dehydrated microbiological medium to be reconstituted in purified water and solidified with its agar component.

• Reconstitution medium (general, literature): Purified/deionized water per pharmacopeial quality suitable for microbiological media preparation.
• Miscibility: The powder disperses in water; agar requires heating to melt. Not intended for use with organic solvents.
• Practical tips:
  • Add powder slowly to cold or room‑temperature water with vigorous stirring to prevent clumping.
  • Heat to dissolve agar fully (bring to near boiling), then sterilize by autoclaving.

For solvent choice in downstream applications (e.g., disinfectant neutralization or surface sampling), consult specific neutralizers or diluents; they are separate reagents and not part of this medium.

Storage and Reconstitution

• Storage conditions (item-specific): Room temperature (per Product Data). Keep container tightly closed in a dry place. Protect from moisture and microbial contamination. Avoid excessive heat.
• Shipping: Normal (per Product Data).
• Reconstitution/preparation (literature typical; verify label/CoA for this item):
  • Use ~40 g/L in purified water. Disperse powder with stirring; heat to dissolve fully.
  • Sterilize by autoclaving at 121 °C for 15 minutes.
  • Cool to 45–50 °C before pouring plates or adding heat‑labile supplements.
• Plate storage (general guidance): Store poured plates in sealed sleeves or bags to prevent desiccation, typically at 2–8 °C, inverted. Allow plates to equilibrate to room temperature before use to minimize condensation. Observe recommended shelf life and perform sterility checks on stored plates.
• Freeze–thaw: Not applicable to dehydrated powder. Do not freeze prepared plates unless validated; freezing damages agar gel structure and performance.
• Stability considerations: Moisture uptake can cause clumping and may affect pH/performance. If caking or discoloration is noted, evaluate performance (e.g., GPT) before use.

For research use only (per Product Data). Always consult the CoA/Spec Sheet for lot‑specific instructions and performance specifications for SKU S1528405.

Structure and Identity

Soybean-Casein Digest Agar (USP) is a complex, multi‑component, dehydrated culture medium (commonly known as Tryptic Soy Agar, TSA) rather than a single defined chemical entity.

• Item identity: Soybean-Casein Digest Agar Medium (USP); dehydrated powder blend intended for preparation of solid microbiological medium.
• Composition (typical, literature): enzymatic (pancreatic) digest of casein, enzymatic (papaic) digest of soybean meal, sodium chloride, agar; often adjusted to pH ~7.3 at 25 °C after sterilization. Exact formulation can vary by supplier.
• Molecular formula: Not applicable (mixture).
• Molecular weight: Not applicable (mixture).
• SMILES / InChIKey: Not applicable for mixtures of undefined peptides and polysaccharide gelling agent.
• Structural features (descriptive):
  • Peptone fraction: heterogeneous short peptides, free amino acids, and small nitrogenous compounds derived from casein and soybean proteins.
  • Mineral content: primarily NaCl for osmotic balance.
  • Gelling matrix: agar (galactose-based polysaccharides agarose/ agaropectin) providing a ~1.5% w/v gel at typical preparation.
• Stereochemistry: Not applicable; mixture of natural L‑amino acid–derived peptides and polysaccharides without a single defined stereochemical center.

Item-specific identifiers (CAS, CID, exact composition): Not specified for this item; refer to CoA/Spec Sheet.

Note on USP designation (general): The “USP” naming reflects alignment with compendial Soybean‑Casein Digest media used in pharmacopeial microbiological tests; verify item-specific conformity and formulation on the CoA for this SKU (S1528405).

Synthetic Utility

Not a chemical building block or reagent for organic synthesis. Instead, its “utility” lies in enabling microbiological workflows. The following focuses on practical laboratory utility (general literature guidance):

• Colony isolation and enumeration: Provides a firm, clear surface conducive to discrete colony formation for CFU determination by spread, pour, or membrane filtration methods.
• Compatibility with supplements: Can be supplemented post‑sterilization (cooled to 45–50 °C) with heat‑labile additives (e.g., blood, antibiotics, neutralizers) to tailor selectivity/enrichment.
• Recovery of stressed organisms: Non‑selective nature and rich peptone profile aid resuscitation following sanitization or sublethal processing.
• Downstream analyses: Colonies recovered on TSA are commonly used for biochemical testing (e.g., catalase, oxidase), MALDI‑TOF identification, or DNA extraction, given minimal interfering dyes/inhibitors.
• Plate-based validation: Suitable as a baseline non‑selective control medium when comparing recovery across selective or differential formulations in method development.

Constraints:

• Not recommended as sole medium for fastidious organisms without enrichment.
• Lacks indicators/chromogens; differentiation requires supplemental tests.

If your application requires defined nutrient composition (e.g., metabolic flux analysis), consider a chemically defined medium instead; TSA is complex and compositionally variable between lots (within specification limits). Always verify lot performance via growth promotion testing.

Target Specificity

Not an antibody, enzyme, or molecular probe. This medium is non‑selective and does not possess target specificity for particular antigens or species.

• General performance (literature): Supports a wide range of aerobic and facultative anaerobic bacteria. For selective recovery, use appropriate selective/differential media or add supplements as required by your method.

No clone, isotype, antigen, or species‑reactivity information applies to this product.