{"id":"9c5f93df-0d17-57a3-a382-9b315a7af416","stable_key":"7edf94bb-95c8-5234-9161-9eb338bb9b36:boron-riboflavin-adduct","predicate":"forms_putative_complex","statement":"An additional m/z 401.3 ion was consistent with a 1:1 riboflavin–boric-acid complex in alkaline electrospray experiments; the ribityl binding site was not resolved.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"6c8a1427-3d97-5267-9c5f-feb2bc2cd100","mechanism_event_label":"A laboratory signal suggests boron can attach to vitamin B2; this does not prove that usual boron intake depletes B2.","subject":{"id":"86eb1eee-a8d1-539c-8c17-0911f69b6f1b","slug":"riboflavin","display_name":"Riboflavin (vitamin B2)","entity_type_key":"small_molecule"},"object":{"id":"9bccbaed-2934-510a-936d-7c7bce6f77a0","slug":"boric-acid-riboflavin-complex","display_name":"Putative 1:1 boric-acid–riboflavin complex","entity_type_key":"chemical_species"},"evidence_count":1,"mechanism_event":{"id":"6c8a1427-3d97-5267-9c5f-feb2bc2cd100","stable_key":"7edf94bb-95c8-5234-9161-9eb338bb9b36:boron-riboflavin-adduct-event","event_type":"biochemical_relationship","label":"A laboratory signal suggests boron can attach to vitamin B2; this does not prove that usual boron intake depletes B2.","description":"An additional m/z 401.3 ion was consistent with a 1:1 riboflavin–boric-acid complex in alkaline electrospray experiments; the ribityl binding site was not resolved.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"56db2f3c-f247-573f-bb7c-47cac02ea60f","slug":"boric-acid","display_name":"Boric acid / orthoboric acid / B(OH)3","entity_type_key":"small_molecule"},"role":"binding_partner","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"86eb1eee-a8d1-539c-8c17-0911f69b6f1b","slug":"riboflavin","display_name":"Riboflavin (vitamin B2)","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"9bccbaed-2934-510a-936d-7c7bce6f77a0","slug":"boric-acid-riboflavin-complex","display_name":"Putative 1:1 boric-acid–riboflavin complex","entity_type_key":"chemical_species"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/boron-research/42012780.fulltext.txt\", \"locator\": \"Exact primary full-text span; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"673f9c1649ebaea729fb8331f6394dcad15d21b7bea8e6414542210b8e9fdd69\", \"start_char\": 6857, \"end_char\": 8798, \"text_sha256\": \"09a30283b0d51a099a2687875db729353a5f03f83f616c974d75a284679f1f8f\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Negative-ion electrospray mass spectrometry","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"200 µM riboflavin and 400 µM boric acid in WAT solvent at pH 10.3","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Nominal mass is consistent with, but does not uniquely establish, the proposed 1:1 structure. No site-resolving NMR or in-vivo binding measurement; signal intensity is not a bound fraction.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Boron research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"boron","display_name":"Boron","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Cell-free chemistry","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A laboratory signal suggests boron can attach to vitamin B2; this does not prove that usual boron intake depletes B2.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[boron-p42012780] Identification of a Riboflavin-Boric Acid Complex by Electrospray Ionization Mass Spectrometry. (2026). https://pubmed.ncbi.nlm.nih.gov/42012780/ DOI: 10.1007/s12011-026-05110-9","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified riboflavin in alkaline solvent","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"2a62107a-966f-5b35-b3b6-7c9ab40c161e","evidence_kind":"source_excerpt","locator":"Lines 183-194","start_line":183,"end_line":194,"excerpt":"### boron-riboflavin-adduct\nAn additional m/z 401.3 ion was consistent with a 1:1 riboflavin–boric-acid complex in alkaline electrospray experiments; the ribityl binding site was not resolved.\nCondition category: normal\nnutrient_topic: Boron research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A laboratory signal suggests boron can attach to vitamin B2; this does not prove that usual boron intake depletes B2.\norganism: Cell-free chemistry\ntissue_or_cell_type: Purified riboflavin in alkaline solvent\nexperimental_model: Negative-ion electrospray mass spectrometry\nlimitations: Nominal mass is consistent with, but does not uniquely establish, the proposed 1:1 structure. No site-resolving NMR or in-vivo binding measurement; signal intensity is not a bound fraction.\nexposure: 200 µM riboflavin and 400 µM boric acid in WAT solvent at pH 10.3\nevidence_span: {\"source_cache\": \"artifacts/boron-research/42012780.fulltext.txt\", \"locator\": \"Exact primary full-text span; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"673f9c1649ebaea729fb8331f6394dcad15d21b7bea8e6414542210b8e9fdd69\", \"start_char\": 6857, \"end_char\": 8798, \"text_sha256\": \"09a30283b0d51a099a2687875db729353a5f03f83f616c974d75a284679f1f8f\"}\n[boron-p42012780] Identification of a Riboflavin-Boric Acid Complex by Electrospray Ionization Mass Spectrometry. (2026). https://pubmed.ncbi.nlm.nih.gov/42012780/ DOI: 10.1007/s12011-026-05110-9","model_system":"Negative-ion electrospray mass spectrometry","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [boron-p42012780] Identification of a Riboflavin-Boric Acid Complex by Electrospray Ionization Mass Spectrometry. (2026). https://pubmed.ncbi.nlm.nih.gov/42012780/ DOI: 10.1007/s12011-026-05110-9","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"2d96c547-aeec-5d8b-9d31-1288da209f89","stable_key":"import-7edf94bb-95c8-5234-9161-9eb338bb9b36","title":"Boron: chemistry, nutrient interactions, low-intake studies and mechanistic uncertainties (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"0a32c1c5c70cfb4a378f6ace35cf5b75d90ed3065ada91b9f9f64015d603c8e3","revision_id":"38f316f2-4344-542e-a638-0ac5402f678d","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}