Malt Extract Broth - BioReagent

Cat. No.: M1528620

GRADE & PURITY BioReagent

Storage

Room temperature

Shipped In

Normal

Overview

Contains 0.6% malt extract powder, chloramphenicol-free, for the cultivation of molds and yeasts

Specifications

Specifications & Purity

BioReagent

Storage

Room temperature

Shipped In

Normal

Grade

BioReagent

Product Line

biological_products

Application Protocols

The following are general, literature-based procedures. For exact mass-per-liter and any item-specific instructions, refer to the product label/CoA.

• Preparation of Malt Extract Broth (literature example)

  1. Weigh the manufacturer-recommended quantity of dehydrated MEB powder per liter. If unavailable, typical formulations range from 20–30 g/L total solids depending on brand; this is guidance only.
  2. Add to ~80% of the final volume of deionized water with stirring until fully dissolved.
  3. Adjust pH to the target value (commonly ~5.4 at 25 °C) with sterile 1 N HCl/NaOH if required by your protocol.
  4. Bring to final volume with water; dispense into suitable vessels with headspace.
  5. Sterilize by autoclaving at 121 °C for 15–20 min. Allow to cool to 45–50 °C if aseptically adding heat-labile supplements via 0.22 µm filtration.

• Yeast cultivation in shake flasks (literature)

  • Inoculate sterile MEB with a fresh overnight culture to OD600 ~0.1.
  • Incubate at 28–30 °C, 180–220 rpm, fill volume ≤20% of flask volume.
  • Sample periodically for OD600, pH, and metabolite assays (e.g., ethanol, glucose).

• Mold cultivation (literature)

  • Inoculate with a defined spore suspension (e.g., 10^4–10^6 spores/mL depending on species).
  • Incubate static or with gentle agitation at 25–28 °C; monitor pellet formation and biomass.

• Quality checks

  • Verify sterility (uninoculated control), pH post-sterilization, and growth promotion with a reference strain as required by your SOP.

Biological Roles

Not a single biomolecule: Malt Extract Broth is a complex nutrient mixture and does not possess a specific “biological role” as a metabolite or signaling agent.

• General context (literature)

  • Nutrient provision: Supplies fermentable carbohydrates (maltose, glucose, dextrins), amino nitrogen, minerals, and B-vitamins that support growth and metabolism of fungi and yeasts.
  • Metabolic pathways engaged: Glycolysis and fermentation (ethanol/CO2) in yeasts on maltose/glucose; pentose phosphate pathway for NADPH generation; biosynthesis of amino acids and nucleotides fueled by provided nitrogen and vitamins.
  • Ecology of use: Acidic pH favors acid-tolerant microbes and suppresses many neutrophilic bacteria, biasing cultures toward fungi/yeasts.
  • Phenotypic effects: Carbohydrate complexity can influence morphology (e.g., hyphal development, sporulation) and metabolite production profiles (secondary metabolites) in filamentous fungi, depending on strain and conditions.

• Limitations (general)

  • Undefined composition can confound omics studies requiring precise nutrient control; defined media may be preferable for metabolic modeling.
  • Different lots or brands may vary in vitamin/mineral content, affecting growth kinetics and yields; lot qualification is recommended for critical experiments.

Buffer Applications

Malt Extract Broth is not a dedicated buffering agent and is not typically used to prepare classical buffer systems.

• General/literature notes
  • Intrinsic buffering: Complex organic acids and phosphates present in malt extract impart limited buffering capacity around mildly acidic pH, commonly near 5–6 in typical formulations.
  • If precise buffering is required: Supplement with defined buffer components (e.g., citrate-phosphate for pH 5–6, or MES for pH ~6) while verifying organism tolerance. Sterilize buffers separately if heat-labile and combine aseptically.
  • Impact on assays: Background absorbance and color of malt extract may interfere with spectrophotometric pH indicator assays; use appropriate blanks and controls.

For dedicated buffer preparation, consider standard biological buffers (phosphate, citrate, MES, MOPS) rather than complex media.

Green Alternatives

Context: Malt Extract Broth is itself plant-derived in large part (malted barley extract), and is used as an aqueous medium. Environmental considerations focus on sourcing, sterilization energy, and waste handling rather than solvent substitution.

• Greener practice options (general)

  • Renewable feedstock: Prefer malt extract sourced from sustainably farmed barley; consult supplier statements on sourcing and processing.
  • Energy efficiency: Optimize autoclave loads, use validated liquid cycles, and avoid over-sterilization that wastes energy and degrades media.
  • Waste minimization: Prepare only volumes needed; segregate uncontaminated packaging waste from biohazardous waste. Deactivate cultures before disposal via autoclave to prevent environmental release.
  • Reusable labware: Where biosafety permits, use glass flasks and stainless-steel caps instead of single-use plastics; validate cleaning/sterilization SOPs.
  • Additive stewardship: Add antibiotics/selective agents only when necessary; dispose of antibiotic-containing waste per institutional guidelines.

• Alternatives to consider (literature, application-dependent)

  • Potato Dextrose Broth (PDB): Also plant-derived; different carbohydrate profile may alter fungal growth and metabolite spectra.
  • Sabouraud Dextrose Broth (SDB): Higher dextrose; often supports robust yeast growth but is less “natural malt” oriented.
  • Defined synthetic yeast media (e.g., YNB + defined carbon source): Reduce variability and may lessen batch qualification needs, at the cost of natural-complex nutrients.

• Trade-offs

  • Complex, plant-based media reduce reliance on animal-derived peptones, but lot variability can be higher than in fully defined media.

Pharmaceutical Uses

No therapeutic claims are made. The following relates to laboratory and manufacturing support roles.

• General/literature uses in pharma/biotech QC and development

  • Growth promotion testing (GPT): As a non-selective fungal medium, Malt Extract Broth can be used to verify suitability of test methods by supporting specified organisms’ growth in compendial-style verifications (use per internal SOP; confirm acceptance criteria).
  • Environmental monitoring: Recovery of airborne or surface fungal contaminants in cleanroom investigations (broth enrichment prior to plating).
  • Raw material/utility testing: Enrichment of yeast/mold contaminants from water systems or excipients before enumeration on agar.
  • Seed train research: Academic or preclinical fermentation studies involving yeasts where complex carbon sources are desired (research use only).

• Regulatory context

  • Not specified as meeting pharmacopeial monographs in the Product Data. If compendial compliance is required (e.g., USP/EP/JP media), verify suitability or select a medium labeled accordingly.

• Documentation and validation

  • For GMP-adjacent use, obtain CoA and perform incoming verification (pH, sterility after autoclave, clarity, and GPT per organisms relevant to your SOPs).

Physical Properties

• Item-specific data

  • Appearance: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular weight (single value): Not applicable (mixture).
  • Density, refractive index, UV cutoff, water/peroxide/metal limits: Not specified for this item; refer to CoA/Spec Sheet.

• General/literature properties of Malt Extract Broth (informational, not product specifications)

  • Physical state: Free-flowing tan to light-brown dehydrated powder; produces a clear to slightly opalescent amber solution upon dissolution in water (literature).
  • Solubility: Freely soluble in water; insoluble in most organic solvents (literature).
  • pH of prepared broth: Commonly around pH 5.4 (±0.2) at 25 °C for typical formulations, supporting fungal growth and suppressing many bacteria (literature; exact pH depends on manufacturer and recipe).
  • Osmolality: Variable; increases with solids concentration (literature).
  • Hygroscopicity: Moderate — can absorb atmospheric moisture leading to caking and variability in weigh-outs; store tightly closed (literature guidance).
  • Thermal behavior: Intended to withstand routine moist-heat sterilization cycles (e.g., autoclaving) without significant caramelization when conditions are controlled; overheating can darken the medium and reduce fermentable sugar content (literature).

• Practical notes (general)

  • Water quality meaningfully impacts clarity and performance; use ASTM Type I/II or equivalent deionized water (literature).
  • Filter sterilization may be used for heat-labile supplements added post-autoclave (literature).

Quality & Grades

• Item-specific grade

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

• What BioReagent grade generally implies (general/literature)

  • Intended for laboratory research use, including microbiology and biotechnology workflows.
  • Typically manufactured to consistent nutrient performance criteria (e.g., growth promotion testing of representative microorganisms), though exact acceptance criteria vary by supplier and lot; verify with CoA.
  • Emphasis on low bioburden and controlled ash/heavy metal content may be part of supplier specifications; specific numerical limits for this catalog item are not provided here. For any item-specific limits (metals, pH, clarity, growth response), refer to the CoA/Spec Sheet.

• Considerations for complex media

  • Lot-to-lot variability is managed through blending and performance testing, but minor shifts in growth kinetics and morphology can occur; critical applications should qualify lots with your strains.
  • If your workflow is regulated (e.g., QC microbiology), confirm whether a lot-specific growth promotion test (GPT) summary is available.

• Stabilizers and additives

  • No stabilizer is declared in Product Data. If your application is sensitive to specific inhibitors (e.g., antibiotics), review the CoA to confirm absence.

• Documentation

  • Request and retain CoA and, where applicable, TDS/SDS for your quality records. Align your acceptance criteria (pH, sterility after autoclave, growth promotion) with your internal SOPs.

Reaction & Applications

This product is a microbiological growth medium rather than a reagent for chemical synthesis. Accordingly, “applications” pertain to cultivation and analysis of microorganisms.

• Research and industrial applications (general/literature)

  • Cultivation of yeasts and molds for routine propagation, strain maintenance, and biomass production.
  • Fermentation starter cultures for brewing-related research (non-clinical, laboratory use), exploiting maltose/dextrin-rich nutrients.
  • Enumeration and quality assessments of fungal contaminants in environmental, food, and beverage microbiology laboratories.
  • Morphology and sporulation studies of filamentous fungi, where the carbohydrate profile of malt extract influences colony traits.
  • Substrate for biochemical assays (e.g., carbohydrate utilization, ethanol production) by yeasts under defined conditions.

• Practical tips (general)

  • Aeration strongly affects yeast metabolism; shaken flasks (150–250 rpm, baffled) or bioreactors with controlled dissolved oxygen improve reproducibility.
  • Acidic pH (≈5.4, literature) helps suppress many bacteria; for selective suppression, incorporate antibiotics or adjust pH per protocol.
  • Avoid overheating during sterilization; prolonged autoclaving can caramelize sugars and reduce growth yield.
  • For optical density measurements, establish a medium-only blank; malt extract may have a modest background absorbance at 600 nm.

• Not applicable

  • This medium is not used in named organic reactions or as a stoichiometric/catalytic reagent.

Reaction Conditions

Interpreted as culture conditions for microbial growth rather than chemical reactions.

• General/literature culture conditions for yeasts/molds in Malt Extract Broth (not product specifications)

  • Reconstitution: Dissolve the manufacturer-recommended mass per liter in deionized water. Exact mass-per-liter for this item is not specified; refer to CoA/label.
  • Sterilization: Autoclave at 121 °C for 15–20 minutes; avoid prolonged heating to limit sugar degradation.
  • pH: Adjust to approximately 5.4 (±0.2) at 25 °C before sterilization if required by your protocol; verify post-autoclave.
  • Inoculation density: For yeasts, starting OD600 ~0.05–0.1 is common in shaken cultures; for molds, inoculate with spore suspension at defined CFU/spore counts (lab SOP).
  • Incubation: 25–30 °C for many fungi; 28–30 °C is common for Saccharomyces cerevisiae in shake flasks. Time: 18–72 h depending on organism and endpoint (growth, metabolite production).
  • Aeration/agitation: 150–250 rpm in baffled flasks (fill volume ≤20%); in bioreactors, maintain DO above setpoint (e.g., >30%) by adjusting airflow and agitation.
  • Monitoring: Measure OD600 for yeasts; dry weight or colony-forming units for molds. Consider medium blank corrections due to color/turbidity.

• Downstream considerations

  • For metabolomics or enzyme assays, rapidly quench or harvest cells to minimize carryover metabolism; wash pellets with buffered saline to reduce medium background.

Safety & Handling

• Item-specific hazard information

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

• General safety guidance for malt extract–based media (informational)

  • Expected hazards: Low acute toxicity; nuisance dust may cause mechanical irritation to eyes/respiratory tract. Combustible dust hazard possible in powder form; minimize dust generation (literature).
  • Microbiological risk: Once reconstituted and inoculated, cultures contain viable microorganisms. Handle per BSL-appropriate procedures. Decontaminate all waste by autoclaving or approved disinfectants before disposal (institutional biosafety guidance).
  • Incompatibilities: Avoid strong oxidizers. Prevent moisture ingress to maintain quality and flow properties (literature).
  • PPE: Laboratory coat, safety glasses, and appropriate gloves when handling powder and cultures. Use dust mask/respirator if airborne dust is generated (per risk assessment).
  • First aid (overview; consult SDS/medical professional):
    • Inhalation: Move to fresh air; seek attention if irritation persists.
    • Eyes: Rinse cautiously with water for several minutes; remove contact lenses if easy to do; seek attention if irritation continues.
    • Skin: Wash with soap and water.
    • Ingestion: Rinse mouth; seek advice if unwell.
  • Sterilization/decontamination: Autoclave at validated conditions (e.g., 121 °C) for liquid cultures and solid waste; avoid tightly sealing containers during autoclaving to prevent rupture (general lab practice).

Always consult the product SDS and institutional biosafety policies for authoritative safety data and procedures.

Solvent Selection

Malt Extract Broth is a water-based culture medium; solvent selection primarily concerns the quality and treatment of water rather than choosing among organic solvents.

• Item-specific note

  • Primary solvent: Water (for reconstitution). Exact reconstitution mass per liter is not specified for this item; refer to CoA/Spec Sheet/label.

• General/literature guidance

  • Water quality: Use freshly prepared ASTM Type I or II deionized water with low total organic carbon and low endotoxin for sensitive applications. Hard water can cause haze and impact growth.
  • pH control: Typical working pH is mildly acidic (around 5–6 at 25 °C, literature). Adjust with sterile 1 N HCl/NaOH as needed after dissolution and before sterilization; verify after sterilization as pH may shift.
  • Additives: Heat-labile supplements (e.g., antibiotics, vitamins) should be filter-sterilized (0.22 µm) and added aseptically to cooled (45–50 °C) sterile broth.
  • Clarification: If turbidity interferes with optical measurements, filter the prepared, uninoculated medium through a 0.45 µm membrane; note that some carbohydrate-rich media remain slightly opalescent.

• Comparison to alternatives (general)

  • Malt Extract vs. Sabouraud Dextrose or Potato Dextrose media: All support fungi; malt extract provides complex maltose/dextrin carbon sources and B-vitamins from barley, often yielding robust yeast growth at lower pH (literature). Choice depends on organism preference and downstream analytics.

Storage & Reconstitution

• Item-specific storage and shipping

  • Storage conditions: Room temperature (from Product Data). Keep container tightly sealed, dry, and protected from excessive humidity and heat.
  • Shipped in: Normal (from Product Data).

• Reconstitution (general/literature guidance)

  • Mass per liter: Not specified for this item; refer to CoA/Spec Sheet/label for the exact reconstitution amount.
  • Water quality: Use freshly prepared deionized water (ASTM Type I/II). Dissolve with stirring; minor opalescence can be normal for complex media.
  • pH: Adjust per protocol (commonly ~5.4 at 25 °C, literature). Re-check pH after sterilization.
  • Sterilization: Autoclave at 121 °C for 15–20 min unless sterile-filtering is indicated for supplements.

• Prepared broth storage (general)

  • Use freshly prepared sterile broth for best performance. If necessary, store unopened sterile aliquots at 2–8 °C for up to a few weeks (literature); inspect for contamination, precipitation, or darkening before use.
  • Avoid repeated heating cycles; do not freeze unless validated for your application, as freezing can cause component precipitation and performance shifts.

• Stability notes

  • The dehydrated medium is hygroscopic; reseal promptly after use. Caking or color darkening can indicate moisture exposure or overheating during processing.
  • Always follow institutional SOPs and consult the product CoA/SDS for definitive guidance.

Structure & Identity

Brief overview: Malt Extract Broth (MEB) is a complex, undefined microbiological growth medium primarily used for cultivating yeasts and molds.

• Item-specific facts (from Product Data)

  • Product name: Malt Extract Broth (SKU: M1528620)
  • Grade: BioReagent
  • CAS: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.
  • SMILES / InChIKey: Not applicable — complex mixture; not a single defined compound.

• Nature of material (general)

  • Composition: Derived from malted barley extract combined with nutrient sources; an undefined mixture rich in carbohydrates (maltose, glucose, dextrins), amino nitrogen, vitamins, and minerals (literature).
  • Structural features: As a mixture, it contains diverse saccharides and small molecules; no single 2D or 3D structure applies.
  • Form: Typically supplied as a dehydrated powder for reconstitution in water (literature).

• Use class and identity context (general/literature)

  • Use class: Microbiological culture medium for fungi/yeasts; analogous to Malt Extract Agar (MEA) but without agar.
  • Typical role: Non-selective, nutrient-rich medium favoring acidophilic/acid-tolerant organisms, notably Saccharomyces, Candida, and filamentous fungi (literature).

Synthetic Utility

Not applicable as a chemical reagent. Malt Extract Broth is not used as a substrate, catalyst, or solvent in organic synthesis.

• General note (literature)
  • As a complex aqueous medium, it may interfere with chemical reactions due to high carbohydrate content and undefined components; avoid use in synthetic chemistry workflows.
  • For biocatalysis with yeasts, specialized fermentation media or defined buffers are typically preferred for reaction optimization and analytics.

Target Specificity

Not applicable. This product is a culture medium, not a biologic with antigen/epitope specificity. No clone/isotype/species reactivity data are relevant.