Standard I Nutrient Agar - BioReagent

Cat. No.: S1528303

GRADE & PURITY BioReagent

Storage

Room temperature

Shipped In

Normal

Descripción general

For bacterial cultivation, nutrient-rich; may be used as a basal medium for blood agar and for Streptococcus and other media

Specifications

Especificaciones y pureza

BioReagent

Condiciones de almacenamiento de almacenamiento

Room temperature

Enviado en

Normal

Grado

BioReagent

Product Line

Productos biológicos

Application Protocols

General protocols (literature) for routine use. Item-specific instructions are Not specified for this item; refer to CoA/Spec Sheet.

• A. Plate preparation

  • Reconstitute and sterilize the medium as described under Reaction Conditions. Cool to ~45–50 °C and pour into sterile Petri dishes. Allow to solidify and, if needed, dry plates in a laminar-flow hood until the surface is free of excess moisture.

• B. Streak plate for isolation

  • Flame-sterilize a loop, cool, and streak the sample across quadrants to dilute cells. Incubate plates inverted at the organism-appropriate temperature. Examine colony morphology and purity.

• C. Spread plate enumeration

  • Pipette a defined volume (e.g., 0.1 mL) of diluted sample onto the plate. Spread with a sterile spreader until absorbed. Incubate and count CFU, accounting for dilution factors.

• D. Pour plate enumeration

  • Pipette measured sample into a sterile plate; add ~15 mL of tempered (45–50 °C) medium. Swirl gently, allow to solidify, then overlay if needed. Incubate and count colonies in and on the agar.

• E. Short-term maintenance

  • Streak pure cultures, incubate to obtain isolated colonies, then store plates sealed at 2–8 °C. Subculture periodically per SOP.

Adjust all parameters to organismal requirements and laboratory SOPs.

Biological Roles

While not a biomolecule with intrinsic biological activity, Standard Nutrient Agar provides a supportive environment for microbial growth.

• Functional role (literature):
  • Carbon and energy sources: Complex hydrolysates (e.g., peptones, beef/yeast extract) supply amino acids, peptides, carbohydrates, and vitamins that support heterotrophic bacterial metabolism.
  • Nitrogen sources: Peptides and amino acids enable biosynthesis of cellular macromolecules.
  • Ionic/osmotic balance: Sodium chloride (when present) maintains extracellular osmotic conditions conducive to growth of many nonfastidious bacteria.
  • Physical scaffold: Agar forms a porous, inert gel allowing diffusion of nutrients and metabolic byproducts while maintaining colony separation and morphology for isolation and enumeration.
• Physiology and outcomes:
  • Non-selective: supports a broad range of mesophilic aerobes and facultative anaerobes; lacks inhibitors or indicators (literature).
  • Limited buffering: pH may drift during growth; plates are best used within recommended time frames and storage conditions to maintain performance (literature).

Item-specific composition and performance characteristics are Not specified for this item; refer to CoA/Spec Sheet.

Buffer Applications

This product is not a dedicated buffering system. Nutrient agar provides limited intrinsic buffering capacity via its complex components.

• If buffering is needed (literature):
  • Use defined buffers (e.g., phosphate, HEPES) in separate applications or select media formulated with explicit buffering systems.
  • For assays sensitive to pH drift, consider preparing parallel buffered broths or defined media and compare performance.

For pH specifications of the prepared medium, Not specified for this item; refer to CoA/Spec Sheet.

Green Alternatives

From a green chemistry perspective, nutrient agar media are water-based and typically free of volatile organic solvents, aligning with principles of safer solvents and auxiliaries.

• Environmental considerations (literature):
  • Water is the sole solvent; preparation avoids VOC emissions and flammable solvents.
  • Agar is derived from renewable seaweed biomass; however, sourcing sustainability varies by supplier.
  • Energy use stems from autoclaving; optimize batch sizes and use validated sterilization cycles to reduce energy consumption.
• Alternative media choices and trade-offs:
  • Plant-derived peptones/yeast extracts can replace animal-derived components to improve sustainability and address regulatory preferences (trade-off: growth profiles may shift; validation required).
  • Dehydrated ready-to-use broths (no agar) reduce energy for melting but eliminate the benefits of solid media.
• Waste minimization:
  • Prepare only the volume needed; remelt once if permitted by your SOP to avoid discarding unused plates (excessive re-melting can reduce gel strength; literature).
  • Autoclave and segregate biohazard waste efficiently; consider reusable glass Petri dishes when appropriate to reduce plastic waste.

Note: Item-specific sustainability claims are not provided. Practices above are general guidance.

Pharmaceutical Uses

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

• Typical roles in regulated environments (literature):
  • General-purpose solid medium for environmental monitoring isolates, raw material bioburden screening, and maintenance of nonfastidious environmental isolates in QC microbiology labs.
  • Use in method development and training for plate-based enumeration where selective/differential media are not required.
• Standards and documentation:
  • Where compendial alignment is required (e.g., USP/EP microbiology chapters), organizations typically specify media formulations and performance tests; item-specific conformity is Not specified for this item; refer to CoA/Spec Sheet and internal validation.
• Formulation/packaging: Not specified for this item; refer to CoA/Spec Sheet.

Users should perform internal qualification (growth promotion, sterility, pH) before use in GMP/QC workflows.

Physical Properties

Item-specific physicochemical specifications are not provided in the Product Data.

• Appearance (dehydrated): Not specified for this item; refer to CoA/Spec Sheet. Typical products are tan to beige, free-flowing powders (literature).
• Solubility: Dispersible in water; agar portion requires heating to near boiling to dissolve fully (literature). Insoluble in organic solvents.
• Gel behavior (agar matrix, literature):
  • Melting (Tm) typically ~80–90 °C for standard agar.
  • Gelation (Tg) typically ~32–40 °C; gels firm below ~40–45 °C.
  • Thermoreversible gel; reheating remelts.
• pH of prepared medium: Not specified for this item; refer to CoA/Spec Sheet. Nutrient agar formulations commonly target pH ~6.8–7.4 at 25 °C (literature).
• Density / bulk density (powder): Not specified for this item; refer to CoA/Spec Sheet.
• Osmolality / ionic strength: Not specified for this item; refer to CoA/Spec Sheet.
• Sterilization: Typically by autoclaving at 121 °C for 15 min (literature). Avoid overheating to minimize Maillard reactions and nutrient degradation.
• Shelf life: Not specified for this item; refer to CoA/Spec Sheet.

Important

• Values above labeled “literature” are general expectations for nutrient agar media and are not item-specific specifications. Consult the item’s CoA/Spec Sheet for definitive data.

Quality and Grades

• Grade: BioReagent — indicates suitability for laboratory biological research applications. Typically emphasizes low bioburden, consistent performance in culture applications, and controlled lot-to-lot variability.
• What BioReagent means in practice:
  • Manufactured with attention to microbiological quality (e.g., low background contamination) and functional performance in microbial culture (literature, general guidance).
  • Not intended for clinical diagnostic use or as a food additive.
• Item-specific quality attributes:
  • Exact composition, performance criteria (e.g., growth promotion testing), and acceptable ranges for pH/clarity are Not specified for this item; refer to CoA/Spec Sheet.
• Stabilizers / additives: Not specified for this item; refer to CoA/Spec Sheet.
• Documentation: For regulated workflows (QC microbiology, method validation), request and retain the lot-specific CoA and, where applicable, performance certifications (e.g., growth promotion results) to support traceability and audit requirements.
• Practical tip: Validate each new lot against in-house reference organisms and acceptance criteria (e.g., colony counts, morphology, and sterility controls) before large-scale use.

Reaction and Applications

This product is not a chemical reagent for synthetic reactions. Its relevance is in microbiology workflows.

• Primary applications (literature):
  • Routine cultivation, isolation, and maintenance of nonfastidious bacteria from environmental, food, and laboratory samples.
  • Enumeration by spread plate or pour plate methods when a simple, non-selective solid medium is appropriate.
  • Colony morphology assessment, subculture from enrichment broths, and storage of working stocks (short-term) at 2–8 °C once plated.
• Use-cases and practical tips:
  • Pre-warm poured plates to room temperature before inoculation to prevent moisture pooling and swarming artifacts.
  • Dry plates (closed, at room temperature or in a laminar-flow hood) to remove surface condensate for improved streaking and colony isolation.
  • For organisms sensitive to NaCl, verify the medium’s salt content on the CoA/Spec Sheet; choose low-salt alternatives if needed.
  • For anaerobes, this medium is generally unsuitable unless modified; use anaerobic media and appropriate incubation conditions.
• Quality controls (literature):
  • Include sterility controls (uninoculated plates) per batch.
  • Growth-promotion testing with representative strains (e.g., E. coli, S. aureus, P. aeruginosa) is standard practice; item-specific strains and acceptance criteria are Not specified for this item; refer to CoA/Spec Sheet.

All applications are for research use only.

Reaction Conditions

Interpreted here as preparation and use conditions for the medium (general literature guidance). Item-specific instructions are Not specified for this item; refer to CoA/Spec Sheet.

• Typical preparation (literature):
  • Suspend the dehydrated medium in purified water at the manufacturer-recommended concentration (commonly cited around 23 g/L for standard nutrient agar, but follow CoA/Spec Sheet for this item).
  • Heat with frequent agitation to dissolve completely; bring to a brief boil to ensure clarity.
  • Sterilize by autoclaving at 121 °C for 15 minutes.
  • Cool to ~45–50 °C; mix gently to avoid bubbles and pour into sterile Petri dishes (e.g., 20–25 mL per 90 mm plate). Allow to solidify.
• Incubation (literature):
  • Inoculate by streaking, spreading, or pour plate method.
  • Typical incubation for mesophiles: 30–37 °C for 18–48 hours, depending on organism and objective.
• Quality controls:
  • Sterility check: Incubate one uninoculated plate per lot/batch.
  • Growth-promotion testing with representative organisms is recommended; acceptance criteria are lab-specific.
• Storage of prepared plates (literature):
  • Store inverted at 2–8 °C in sealed sleeves or bags to minimize dehydration; equilibrate to room temperature before use. Use within a few weeks or per SOP.

All conditions above are general guidance and not item-specific specifications.

Safety and Handling

• GHS classification / signal word / pictograms / H-statements: Not specified for this item; refer to the SDS for authoritative safety information.
• General hazards (literature/common for dehydrated culture media):
  • Low acute toxicity expected; may cause mechanical irritation to eyes, skin, or respiratory tract as dust. Use appropriate dust control.
  • Post-use, agar plates and broths are biohazardous if inoculated; autoclave before disposal.
• Recommended PPE: Lab coat, safety glasses, and appropriate gloves. Use a dust mask/respirator if dust generation cannot be controlled.
• Handling:
  • Prepare media in well-ventilated area; avoid creating dust clouds.
  • When heating to dissolve agar, use vessels with headspace to prevent boil-over; swirl cautiously to avoid bumping and scalds.
  • Use heat-resistant gloves for handling hot media; cool to ~45–50 °C (literature) before pouring plates to avoid condensation and thermal shock.
• Incompatibilities: Strong oxidizers and strong acids/alkalis may degrade organic components (general chemical compatibility). Avoid prolonged exposure to moisture; store tightly closed.
• First aid (overview): If inhaled, move to fresh air; if in eyes, rinse cautiously with water; if on skin, wash with soap and water. Seek medical attention if irritation persists. Refer to SDS for full guidance.
• Spill/cleanup: Avoid dust; sweep or HEPA vacuum. For liquid media, absorb with inert material. Decontaminate biologically contaminated waste by autoclaving.

Solvent Selection

This product is a dehydrated microbiological medium intended for reconstitution in water.

• Primary solvent: Purified water (ASTM Type I/II or equivalent). Avoid high ionic strength or contaminated water that can alter gel strength and microbial performance.
• Miscibility: Agar-based media are prepared exclusively in water; organic solvents are inappropriate and will disrupt gelation and growth.
• Water quality considerations (literature):
  • Use freshly prepared, deionized/distilled water; avoid residual chlorine or heavy metals which can inhibit growth.
  • For sensitive assays, pre-equilibrate water to room temperature to improve dissolution control and reduce condensation during plate pouring.
• When to choose this medium vs alternatives:
  • Choose Standard Nutrient Agar for routine cultivation and maintenance of nonfastidious bacteria and for environmental isolation where rich, undefined nutrients are acceptable.
  • Consider Tryptic Soy Agar (TSA) or Plate Count Agar (PCA) for broader recovery in QC testing; choose selective/differential media (e.g., MacConkey, MSA) when targeting specific taxa (literature).

Storage and Reconstitution

• Storage (as supplied): Room temperature (per Product Data). Keep container tightly closed in a dry place to prevent moisture uptake and caking. Protect from excessive heat and humidity.
• Shipping: Shipped at ambient temperature (per Product Data: Normal).
• Reconstitution: Exact mass per liter and target pH are Not specified for this item; refer to CoA/Spec Sheet.
  • General guidance (literature): Suspend the recommended mass of dehydrated medium in purified water; heat with agitation to fully dissolve; bring to a brief boil to clarify.
  • Sterilize by autoclaving at 121 °C for 15 minutes. Do not over-autoclave to avoid nutrient caramelization and loss of gel strength.
  • After autoclaving, cool to ~45–50 °C before pouring plates or dispensing into containers. Avoid condensation by equilibrating poured plates at room temperature before use.
• Reuse / remelting (literature): The gel is thermoreversible; remelt once if permitted by SOP. Repeated autoclaving can degrade medium performance.
• Prepared media storage (literature): Store solid plates inverted at 2–8 °C in sealed sleeves to minimize dehydration; store liquid media at 2–8 °C. Use within recommended time frames defined by your SOP.
• Research use note: For research use only (per Product Data). Refer to the item’s CoA/Spec Sheet and SDS for definitive specifications and safety information.

Structure and Identity

This product is a complex, dehydrated culture medium formulated for routine cultivation of nonfastidious microorganisms.

• Product type: Complex mixture (nutrient medium with gelling agent); not a single defined chemical entity.
• Intended form: Dehydrated medium that forms a firm gel upon dissolution, sterilization, and cooling.
• Molecular formula / Molecular weight: Not applicable to mixtures. Not specified for this item; refer to CoA/Spec Sheet.
• SMILES / InChI / InChIKey: Not applicable for complex mixtures.
• Structural features (descriptive):
  • Contains an agar-type polysaccharide gelling matrix (linear galactans; literature) providing a solid surface for colony formation.
  • Includes complex nitrogen and carbon sources (e.g., peptones and beef/yeast extract; literature) furnishing amino acids, peptides, vitamins, and growth factors.
  • May include sodium chloride to maintain osmotic balance (literature).
• Two-dimensional description: A heterogeneous blend of low–molecular-weight nutrients dispersed within a high–molecular-weight agar network. Upon heating in water, agar dissolves; on cooling, it forms a thermoreversible gel entrapping the soluble nutrient fraction (literature).

Notes

• Composition of “Standard I Nutrient Agar” varies by manufacturer. Any detailed component list or exact concentrations are Not specified for this item; refer to CoA/Spec Sheet.
• For research use only (as indicated).

Synthetic Utility

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

• For chemical synthesis needs, consult solvent reagents, catalysts, or building blocks. For microbiology workflows, see Application Protocols and Reaction Conditions (media preparation) for practical guidance.

Target Specificity

Not applicable. This product is not a biological binder (e.g., antibody, ligand) and has no target specificity parameters such as antigen, clone, isotype, or species reactivity.