NiSO4 x 7 H2O

Ontology mapping

Primary identifier: CHEBI:53504
Ontology label: nickel sulfate heptahydrate

Nutritional roles

Role
TRACE_ELEMENT
Confidence
0.8
Evidence
- Reference type
  COMPUTATIONAL_PREDICTION
  Reference text
  Inferred from curated media-role name pattern
  Curator note
  Provisional role from a curated name-pattern rule; review recommended.

Synonyms (1)

Synonym	Type	Source	Occurrences
NiSO4・7H2O	HYDRATE_FORM	kg_microbe

Rejected enrichment labels (5)

Provenance-only candidates: these are not synonyms and do not resolve to this record.

Rejected label	Disposition	Source
NiSO4 . 6H2O	REJECTED_LABEL	kg_microbe
NiSO4 x 6 H2O	REJECTED_LABEL	kg_microbe
NiSO4·6H2O	REJECTED_LABEL	kg_microbe
NiSO4・6H2O	REJECTED_LABEL	kg_microbe
nickel(2+) sulfate	REJECTED_LABEL	chebi_synonym_review

Chemical properties

Data source: CultureBotHT/compounds_to_cas.csv
Retrieval date: 2026-04-09T00:32:50.689620+00:00
Molecular formula: Ni.O4S.7H2O
Inchi: InChI=1S/Ni.H2O4S/c;1-5(2,3)4/h;(H2,1,2,3,4)/q+2;/p-2
Smiles: O=S(=O)([O-])[O-].[Ni+2]

Evidence (3)

DATABASE_MATCH via CultureMech

Imported from CultureMech pipeline, quality=DIRECT_MATCH

DATABASE_MATCH via MIM curation (#321)

molecular_formula 'Ni.O4S' -> 'Ni.O4S.7H2O'. The recorded value described the anhydrous salt while the label names a hydrate, understating the mass by 18 g/mol per water. Corrected because the label states 7 water(s) of hydration, and the recorded formula was byte-identical to the anhydrous parent CHEBI:53001's ChEBI formula ('Ni.O4S') — the mark of a value inherited from the parent rather than measured for this record. Water appended in ChEBI's own dot-separated notation.

DATABASE_MATCH via MIM curation (#374/#334)

Promoted from CHEBI:53001 ('nickel sulfate') to the specific hydrate term CHEBI:53504 ('nickel sulfate heptahydrate') — MAPPING_SEMANTICS §3 step 1: the label names a hydrate, ChEBI has the term, so nothing needs minting and no closeMatch question arises. The previous term carried no water while the label states it. Found by cross-checking CultureBotAI/CultureMech#272 (#374/#334).

Occurrence statistics

Total occurrences: 9
Distinct media: 9

Curation history

Timestamp	Curator	Action	New status	Changes
2026-03-09T06:54:18.022301+00:00	import_from_culturemech	IMPORTED	MAPPED	Initial import from CultureMech pipeline
2026-04-09T00:32:50.689620+00:00	enrich_mim_cas_rn_batch	CAS_RN_ADDED	MAPPED	Added CAS-RN 10101-97-0 from CultureBotHT/compounds_to_cas.csv
2026-04-18T00:00:00+00:00	cbclaw_kg_microbe_sweep LLM	ADDED_SYNONYMS	MAPPED	Added 5 synonyms from kg-microbe P4.4 enrichment: NiSO4 . 6H2O, NiSO4 x 6 H2O, NiSO4·6H2O, NiSO4・6H2O, NiSO4・7H2O
2026-05-01T07:35:35.574359+00:00	auto_classify_ingredient_type	AUTO_CLASSIFY_INGREDIENT_TYPE		set ingredient_type=SINGLE_INGREDIENT (CHEBI primary)
2026-05-01T08:08:31.675666+00:00	auto_classify_ingredient_type	AUTO_BACKFILL_CHEBI_CHEMISTRY		molecular_formula=Ni.O4S; inchi=InChI=1S/Ni.H2O4S/c;1-5(2,3)4/h;(H2,1,2,3,4)/q+2;/; smiles=O=S(=O)([O-])[O-].[Ni+2]
2026-05-02T03:12:17.464768+00:00	auto_classify_ingredient_type	AUTO_CLASSIFY_INGREDIENT_TYPE		set ingredient_type=SINGLE_INGREDIENT (chemical structure populated (molecular_formula))
2026-06-02T07:05:13.392094+00:00	infer_roles_from_name_lists	ANNOTATED		Added media role: MINERAL (confidence: 0.80)
2026-06-09T05:23:46.813483+00:00	correct_stale_ontology_labels.py	CORRECTED		ontology_label 'NiSO4 x 7 H2O' -> 'nickel sulfate': synced to canonical CHEBI label (preferred_term 'NiSO4 x 7 H2O' unchanged).
2026-07-20T00:00:00+00:00	migrate_media_roles_to_facets	ANNOTATED		Migrated legacy media_roles to role facets (#128): MINERAL -> nutritional_roles.TRACE_ELEMENT
2026-08-13T00:00:00+00:00	fix_scrambled_hydrate_cas	WITHDREW_WRONG_CAS		cas_rn '10101-97-0' removed (#320/#334). It denotes nickel sulfate hexahydrate, which contradicts the hydration state this record's label states — the #334 scrambling, where one CAS is applied across a salt family regardless of hydration. No verified replacement is available: the record's term CHEBI:53001 is generic nickel sulfate, so its xref 7786-81-4 is the anhydrous CAS — wrong for a heptahydrate. Cleared rather than substituted, because swapping in a second wrong number would read as a correction while still publishing a false identifier.
2026-08-13T00:00:00+00:00	add_water_of_hydration	ADDED_WATER_OF_HYDRATION		molecular_formula 'Ni.O4S' -> 'Ni.O4S.7H2O' (#321); the label states 7 water(s) of hydration, and the recorded formula was byte-identical to the anhydrous parent CHEBI:53001's ChEBI formula ('Ni.O4S') — the mark of a value inherited from the parent rather than measured for this record. Water appended in ChEBI's own dot-separated notation.
2026-08-15T00:00:00+00:00	fix_hydrate_terms_and_twins	PROMOTED_TO_SPECIFIC_HYDRATE		identifier/ontology_id CHEBI:53001 -> CHEBI:53504; Promoted from CHEBI:53001 ('nickel sulfate') to the specific hydrate term CHEBI:53504 ('nickel sulfate heptahydrate') — MAPPING_SEMANTICS §3 step 1: the label names a hydrate, ChEBI has the term, so nothing needs minting and no closeMatch question arises. The previous term carried no water while the label states it. Found by cross-checking CultureBotAI/CultureMech#272 (#374/#334).
2026-08-27T03:16:39.519628+00:00	refresh_occurrence_statistics	CORRECTED		occurrence_statistics 6/6 -> 9/9 (media_count/total_occurrences), derived from distinct CultureMech recipe ids in the #337 occurrence table. The prior values came from the importer retired in #453, whose media_count counted a list truncated to 50 examples (#449). [source=ingredient_occurrences.tsv culturemech_rev=15a4da5c08 rows=194137 distinct_recipes=15257]
2026-09-12T00:00:00+00:00	reject_hidden_hydrate_synonym_collapses	REJECTED_HIDDEN_HYDRATE_SYNONYMS	MAPPED	Marked hidden hydrate synonym(s) as REJECTED_LABEL so this record no longer resolves sibling hydrate identities (#251): 'NiSO4 . 6H2O', 'NiSO4 x 6 H2O', 'NiSO4·6H2O', 'NiSO4・6H2O'.
2026-09-22T20:41:14.285965+00:00	claude LLM	REJECTED_PARENT_NAME_SYNONYMS		Retyped names of the parent compound or of a different hydrate as provenance-only REJECTED_LABEL, because this record is a distinct salt, hydrate or tombstone form and the label index resolved the parent's name here (#232): 'nickel(2+) sulfate'. Preserved original text and source metadata. No identity, mapping, role, or remaining-synonym claim was adjudicated.