{"id":"af44623b-3415-5a7b-8c41-76aea6db16e0","stable_key":"335be270-ea4a-5c8e-ad04-964fd22a439e:vanadium-peroxide-radicals","predicate":"reacts_with_peroxide_to_generate","statement":"In phosphate/ascorbate mixtures with peroxide, reduced vanadium supported hydroxyl-radical generation; omitting phosphate sharply reduced the yield.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"9ef03946-cb49-59df-97d0-cf259a93b854","mechanism_event_label":"A reductant can enable pro-oxidant chemistry when peroxide is also present.","subject":{"id":"656eb223-933b-5a40-b70c-0d77537fe717","slug":"vanadyl-iv","display_name":"Oxovanadium(IV) / vanadyl","entity_type_key":"ion"},"object":{"id":"d0314c8d-29e5-5be5-9ec3-49a3dca66b17","slug":"vanadium-hydroxyl-radical-generation","display_name":"Hydroxyl-radical generation in vanadium redox assays","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"9ef03946-cb49-59df-97d0-cf259a93b854","stable_key":"335be270-ea4a-5c8e-ad04-964fd22a439e:vanadium-peroxide-radicals-event","event_type":"observed_relationship","label":"A reductant can enable pro-oxidant chemistry when peroxide is also present.","description":"In phosphate/ascorbate mixtures with peroxide, reduced vanadium supported hydroxyl-radical generation; 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not proof that vitamin C supplementation causes this injury in people.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vanadium collection; molecular form, preparation, species, exposure and manipulation remain explicit.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vanadium","display_name":"Vanadium","entity_type_key":"nutrient_element"}},{"dimension":"plain_language","value_text":"A reductant can enable pro-oxidant chemistry when peroxide is also present.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"One-electron reduction of vanadate by ascorbate and related free radical generation at physiological pH. · 1994 · https://pubmed.ncbi.nlm.nih.gov/8051539/ · DOI 10.1016/0162-0134(94)85032-1","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"558af1a8-2f71-5a53-841b-a71a36b2b470","evidence_kind":"source_excerpt","locator":"Lines 102-108","start_line":102,"end_line":108,"excerpt":"## vanadium-peroxide-radicals\nA reductant can enable pro-oxidant chemistry when peroxide is also present.\nIn phosphate/ascorbate mixtures with peroxide, reduced vanadium supported hydroxyl-radical generation; omitting phosphate sharply reduced the yield.\nModel: Cell-free ESR spin trapping.\nLimitations: Chemical mechanism under specified reagents; not proof that vitamin C supplementation causes this injury in people.\nEvidence access: Primary abstract\nOne-electron reduction of vanadate by ascorbate and related free radical generation at physiological pH. · 1994 · https://pubmed.ncbi.nlm.nih.gov/8051539/ · DOI 10.1016/0162-0134(94)85032-1","model_system":"Cell-free ESR spin trapping.","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":"e4d5d0ba-529b-540f-96ed-e719d116ccfd","stable_key":"import-335be270-ea4a-5c8e-ad04-964fd22a439e","title":"Vanadium: speciation, phosphate-sensitive enzymes 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. 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