{"id":"50fbf0a1-6200-5230-8dff-74eca195fb45","stable_key":"74ef5bba-ee14-531c-b1bf-d1f297c56bb6:fisetin-iron-chelation","predicate":"complexes","statement":"Buffered chemical assays identified 1:1 and 1:2 iron-fisetin complexes with pH-dependent coordination sites.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"26b119ca-782f-5861-94a6-ce6c9840f7e7","mechanism_event_label":"The same molecule binds metal differently as conditions change.","subject":{"id":"dee05061-c3f3-5226-8054-dd58b76a585d","slug":"fisetin","display_name":"Fisetin","entity_type_key":"small_molecule"},"object":{"id":"463835f0-3540-5b32-8336-8f7e41f04bab","slug":"fisetin-iron-complexes","display_name":"Fisetin-iron complexes, stoichiometry and pH specified","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"26b119ca-782f-5861-94a6-ce6c9840f7e7","stable_key":"74ef5bba-ee14-531c-b1bf-d1f297c56bb6:fisetin-iron-chelation-event","event_type":"observed_relationship","label":"The same molecule binds metal differently as conditions change.","description":"Buffered chemical assays identified 1:1 and 1:2 iron-fisetin complexes with pH-dependent coordination sites.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"dee05061-c3f3-5226-8054-dd58b76a585d","slug":"fisetin","display_name":"Fisetin","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"463835f0-3540-5b32-8336-8f7e41f04bab","slug":"fisetin-iron-complexes","display_name":"Fisetin-iron complexes, stoichiometry and pH specified","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"59d6d1cd-df32-5b58-b950-3188bc7b95d6","slug":"iron-ii","display_name":"Ferrous iron","entity_type_key":"ion"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"1c54abac-4dfd-5303-b0f4-37945245e18e","slug":"citrate","display_name":"Citrate","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Spectroscopy, competition assays and structural calculations.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Fisetin bound iron less strongly than EDTA and citrate under tested conditions; no human iron-depletion outcome measured.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Fisetin collection; molecular form, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"fisetin","display_name":"Fisetin","entity_type_key":"small_molecule"}},{"dimension":"plain_language","value_text":"The same molecule binds metal differently as conditions change.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Comparative spectroscopic and mechanistic study of chelation properties of fisetin with iron in aqueous buffered solutions. Implications on in vitro antioxidant activity. · 2011 · https://pubmed.ncbi.nlm.nih.gov/21431152/ · DOI 10.1039/c0dt01834a","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"76662a4f-d042-525d-b32c-755a896d2006","evidence_kind":"source_excerpt","locator":"Lines 136-142","start_line":136,"end_line":142,"excerpt":"## fisetin-iron-chelation\nThe same molecule binds metal differently as conditions change.\nBuffered chemical assays identified 1:1 and 1:2 iron-fisetin complexes with pH-dependent coordination sites.\nModel: Spectroscopy, competition assays and structural calculations.\nLimitations: Fisetin bound iron less strongly than EDTA and citrate under tested conditions; no human iron-depletion outcome measured.\nEvidence access: Primary abstract\nComparative spectroscopic and mechanistic study of chelation properties of fisetin with iron in aqueous buffered solutions. Implications on in vitro antioxidant activity. · 2011 · https://pubmed.ncbi.nlm.nih.gov/21431152/ · DOI 10.1039/c0dt01834a","model_system":"Spectroscopy, competition assays and structural calculations.","directness":"reported_statement","verification_status":"source_derived_draft","notes":"Original curation paraphrase; evidence access and experimental limitations specified.","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"1108bfff-6504-5152-a51f-ff3d7c27c282","stable_key":"import-74ef5bba-ee14-531c-b1bf-d1f297c56bb6","title":"Fisetin: metabolism, cell-state responses and cross-nutrient mechanisms (2026-09-19)","document_type":"imported_text","citation_label":"AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text.","file_path":"","sha256":"c30e0764cd34bd062cfcbfaf32357ef29dfda30e7d4153c545178140f5054e09","revision_id":"40ff52c0-f4b9-5820-8abb-ff002c6364a4","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}