L-alanine
Enable an AI agent to recognise L-alanine, assess the identity and condition of a particular sample, and determine whether its documented quality supports an intended use.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
recalled by Codex without web access - no source was read
Researched by: Codex
Purpose and description
Enable an AI agent to recognise L-alanine, assess the identity and condition of a particular sample, and determine whether its documented quality supports an intended use.
L-alanine is the (S)-enantiomer of 2-aminopropanoic acid, a proteinogenic α-amino acid with formula C3H7NO2 and a methyl side chain, which humans can synthesize.
It can be Reconcile an L-alanine label against molecular identity, authoritative identifiers and analytical evidence.; Compare a sample's alanine assay and D-alanine content with an intended-use specification.; Calculate a weighed amount or solution preparation using assay basis, water content and measured solubility.; Select condition-appropriate checks for identity, stereochemical composition and sample deterioration.; Accept, quarantine or reject a lot against documented quality and handling requirements.; Link L-alanine to a formulation or biochemical reaction while preserving the boundary between the substance and the containing system..
Distinguishing features
Require evidence for the alpha-amino-acid connectivity of 2-aminopropanoic acid; molecular formula alone cannot distinguish it from beta-alanine.
Require the L configuration, corresponding to the S configuration for alanine, and a suitable stereochemical measurement to distinguish a sample from D-alanine or a racemic mixture.
Distinguish free L-alanine from an alanine residue covalently incorporated into a peptide or protein.
Distinguish the parent amino acid, including its zwitterionic form, from separately identified salts, derivatives and products containing it.
Keep total alanine assay separate from L-alanine fraction: a chemically pure alanine sample can still fail an enantiomeric-purity requirement.
Scope
+ L-alanine molecular identity, absolute configuration and verified chemical identifiers
+ Chemical assay, enantiomeric composition, water content and relevant impurities
+ Solid form, solution state and properties measured under specified conditions
+ Sample provenance, grade, storage history and evidence of deterioration
+ Substance-specific functional suitability, hazard evidence and applicable use requirements
- D-alanine and DL-alanine as independently characterised substances
- Beta-alanine and other constitutional isomers
- Alanine residues within peptides and proteins as independently available L-alanine
- Finished foods, supplements, medicines and other formulations containing L-alanine
- Manufacturing plants, fermentation systems and synthesis processes
- Clinical treatment decisions and organism-level metabolic models
Characteristics
- Verified substance identifiers
- Registry id vr.tr.l-alanine; source-verified CAS, PubChem and EC mappings with represented chemical form Prevents records for unspecified alanine, a racemate, a salt or a mixture from being treated as equivalent.
- Molecular identity
- C3H7NO2; 2-aminopropanoic acid connectivity; L configuration; S absolute configuration Separates composition, connectivity and stereochemistry as distinct requirements for identification.
- Alanine assay
- % mass fraction or amount fraction; specify method and as-received, dry or other reporting basis Supports quantitative preparation without confusing chemical assay with stereochemical purity.
- Enantiomeric composition
- L and D mole fractions, L:D ratio or enantiomeric excess; specify method and detection limits Determines whether a sample meets requirements that depend on L-alanine specifically.
- Water and impurity profile
- Water in % mass fraction; individual impurities in mg/kg, % or method-specific units Changes effective concentration, storage interpretation and suitability for sensitive uses.
- Physical and chemical state
- Solid form or solution; temperature, pressure, solvent, pH and concentration where applicable Makes property values interpretable and separates protonation state from substance identity.
- Solubility
- g/L or mol/L with solvent composition, temperature, pH and equilibration method Supports preparation of solutions and interpretation of precipitation.
- Thermal behaviour
- °C with method, heating rate, atmosphere and distinction between melting and decomposition Prevents an ambiguous thermal value from being used as an ordinary melting or boiling point.
- Optical rotation
- Observed or specific rotation with units, wavelength, temperature, solvent and concentration convention Provides condition-dependent identity evidence but does not by itself establish enantiomeric purity.
- Grade and intended-use qualification
- Declared grade; named specification and edition; intended use; qualification status A grade label alone does not demonstrate that a lot is suitable for a particular application.
- Hazard and regulatory evidence
- Dated SDS, jurisdiction-specific identity and classification records, applicable use requirements Connects handling and use decisions to evidence covering the actual substance form and jurisdiction.
Where this came from
wikidata · CC0 1.0
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 6 bundles · 11 layers · 18 findings · 28 questions.
Alanine identity and stereochemistry Establishes which alanine entity is represented and whether the available evidence supports its L designation.
Alanine connectivity, stereochemical identity and commercial naming can be conflated even when a formula or assay appears correct.
Molecular identity boundaries
Separates L-alanine from constitutional isomers, derivatives and covalently bound residues.
Alpha-alanine parent identity
Record evidence for the parent amino acid's connectivity and the chemical form covered by each identifier.
- Which structural and analytical evidence identifies this material as 2-aminopropanoic acid rather than beta-alanine? definition
- Do the assigned identifiers refer to free L-alanine, unspecified alanine, a salt or another derivative? boundary
L-configuration verification
Tests stereochemical identity separately from total alanine content.
Enantiomer-specific evidence
Record how L-alanine and D-alanine were distinguished and quantified.
- Which validated method establishes the L-alanine fraction and detects D-alanine at the required limit? measurement
- If optical rotation supports identification, are solvent, concentration, temperature and wavelength documented? measurement
Lot composition and quality Describes the composition and qualification of a particular L-alanine lot.
Suitability depends on assay basis, stereochemical contamination and use-relevant impurities rather than the substance name alone.
Assay and impurity accounting
Makes reported purity interpretable and identifies components that matter to use.
Interpretable alanine content
Distinguish total alanine assay from L-specific content, water and other measured impurities.
- Does the assay measure all alanine or L-alanine specifically, and on what mass or amount basis is it reported? measurement
- Which impurities require limits for this use, and what results and detection limits are available for them? measurement
Grade and lot traceability
Connects a grade claim to the lot and specification it actually covers.
Documented quality qualification
Treat grade as an evidenced claim rather than an intrinsic property of every L-alanine sample.
- Which manufacturer, lot, certificate of analysis and specification edition support the declared grade? provenance
- Which intended-use acceptance criteria remain unmet or untested despite the grade label? action
Physical state and preparation Connects solid and solution properties to the conditions under which L-alanine is stored or prepared.
Solution behaviour and thermal observations cannot be used reliably without conditions and an explicit interpretation of the measured event.
Solid and thermal behaviour
Records the solid material and distinguishes phase changes from chemical decomposition.
Conditioned solid properties
Attach sample identity and experimental conditions to solid-form and thermal observations.
- What evidence characterises the solid form, water content and particle properties relevant to the proposed handling? measurement
- Does a reported thermal temperature describe melting, decomposition or overlapping events, and under which test conditions? measurement
Aqueous state and solubility
Describes dissolution and pH-dependent chemical state without creating a new identity for every protonation state.
Solution preparation envelope
Record conditions that determine whether a target L-alanine solution can be prepared and maintained.
- What measured solubility applies to the intended solvent, temperature, pH and concentration basis? measurement
- How do pH adjustment and any introduced counterions affect solution composition and its description as L-alanine material? boundary
Functional use and transformations Relates L-alanine's stereochemical and chemical properties to a specified application or transformation.
Biochemical participation, formulation performance and analytical use impose different requirements that cannot be inferred from identity alone.
Application-specific fitness
Connects a proposed role to measurable requirements on the L-alanine sample.
Role-dependent acceptance
Record the intended function and evidence that the sample meets its particular requirements.
- Is the material intended as a biochemical substrate, formulation ingredient, analytical standard or another explicitly defined input? definition
- Which concentration, enantiomeric-purity, impurity and traceability requirements follow from that role? action
Reaction and incorporation boundaries
Tracks when L-alanine is consumed, chemically changed or incorporated into another entity.
Free alanine versus transformed material
Separate remaining free L-alanine from reaction products and alanine residues in larger molecules.
- Which observed transformation consumes L-alanine, and what evidence identifies the resulting species? measurement
- Does a reported alanine quantity measure free L-alanine, alanine released by hydrolysis or alanine residues within a macromolecule? boundary
Storage, handling and use controls Supports decisions about continued sample suitability and permitted handling using applicable evidence.
Neither a familiar biochemical identity nor an unchanged label establishes the condition or authorised use of a stored lot.
Storage history and requalification
Relates storage events to the need for inspection or repeat analysis.
Continued lot suitability
Record storage requirements, actual exposure history and evidence supporting continued use.
- What supplier or stability evidence supports the storage conditions and retest period for this solid lot or prepared solution? provenance
- Which observed excursions or changes require reassessment of water content, contamination, assay or stereochemical composition? action
Hazard and jurisdictional controls
Links handling and application decisions to current documentation for the relevant material and location.
Evidenced handling and use status
Keep hazard classification, exposure guidance and application-specific requirements distinct and traceable.
- Which dated SDS and jurisdictional records establish the applicable hazard classification and any substance-specific or general dust exposure limits? provenance
- What additional qualification is required before this particular lot can be used in the proposed food, laboratory or pharmaceutical application? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- This is recall only; no sources were consulted.
- Verify applicable grade specifications, jurisdiction-specific permissions, and supplier hazard classification before operational use.
- Thermal decomposition values, solubility, optical rotation, and acid-base constants require sources that specify experimental conditions.
- Which of these check these first hold for the sense of L-alanine this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- Reagent-grade L-alanine
- Food-grade L-alanine
- Pharmaceutical-grade L-alanine
- Which of these kinds and varieties hold for the sense of L-alanine this model covers, and on what evidence? provenance
Identifiers and schemes
Recalled without web access and unsourced; every item is a lead to verify.
- CAS Registry Number - 56-41-7 - Identifies L-alanine specifically; D-alanine and DL-alanine have separate identities.
- PubChem CID - 5950 - Compound identifier for L-alanine.
- IUPAC nomenclature - (2S)-2-aminopropanoic acid - Specifies the absolute configuration of the stereogenic carbon.
- Amino-acid residue codes - Ala; A - Three-letter and one-letter codes for alanine in protein sequences; these are not purity or commercial-grade identifiers.
- Which of these identifiers and schemes hold for the sense of L-alanine this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Ingredient in amino-acid formulations for nutrition.
- Nutrient component in cell-culture and microbial growth media.
- Starting material for peptide synthesis and other chemical synthesis.
- Food ingredient used for taste modification.
- Material in alanine dosimeters, where irradiation-induced radicals are measured by electron paramagnetic resonance.
- Which of these real-world use hold for the sense of L-alanine this model covers, and on what evidence? provenance
Typical measurements
Recalled without web access and unsourced; every item is a lead to verify.
- Molar mass - 89.09 - g/mol
- Isoelectric point in aqueous solution - Approximately 6.0; depends on measurement conditions - pH
- Which of these typical measurements hold for the sense of L-alanine this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Dust can cause mechanical irritation during powder handling.
- D-alanine contamination reduces enantiomeric purity and can compromise stereochemically sensitive applications.
- Chemical or microbial contamination can make a batch unsuitable for food, pharmaceutical, or culture applications.
- Strong heating causes decomposition, so an ordinary boiling point is not an appropriate handling characteristic.
- Which of these failure modes and hazards hold for the sense of L-alanine this model covers, and on what evidence? provenance
Regional variation
Recalled without web access and unsourced; every item is a lead to verify.
- Requirements for use in foods and pharmaceutical formulations depend on jurisdiction and intended product category.
- Which of these regional variation hold for the sense of L-alanine this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- Alanine - Alanine is the broader chemical name; L-alanine explicitly selects the (S) stereoisomer.
- D-alanine - D-alanine has the opposite, (R), configuration at the α-carbon.
- DL-alanine - DL-alanine is a racemic mixture of the L and D enantiomers.
- β-alanine - β-alanine has its amino group on the β-carbon rather than the α-carbon and lacks alanine's stereogenic center.
- L-alanine residue in a protein - A residue is covalently incorporated through peptide bonds; free L-alanine is the standalone amino acid.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of L-alanine this model covers, and on what evidence? provenance
What the second pass must settle
- Does an existing Vercy world model already own L-alanine or provide a broader amino-acid model to which this entry should link?
- Which authoritative CAS, PubChem and EC records map specifically to L-alanine, and how do they distinguish unspecified alanine, salts and mixtures?
- Which reference measurements establish solubility, optical rotation and thermal behaviour under sufficiently explicit conditions?
- Which analytical methods and acceptance limits are appropriate for D-alanine, water and other impurities in each intended grade?
- Which current hazard records, exposure guidance, storage evidence and jurisdiction-specific use requirements apply to the actual material being assessed?