{"id":"be0968c8-78e0-5b2b-a68d-8c5bdef119ac","stable_key":"1310afbd-6010-586e-805d-551d846da421:b6-met-rat-niacin-conversion","predicate":"supports","statement":"Under niacin-free feeding, B6-free rats had lower apparent tryptophan-to-niacin conversion than rats receiving B6.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"dd60b289-0534-53e3-9afa-f6b397fc0086","mechanism_event_label":"B6 shortage reduced this dietary study's estimate of niacin production from tryptophan.","subject":{"id":"c0beb226-8842-501f-a147-cac0d9fa7060","slug":"vitamin-b6","display_name":"Vitamin B6","entity_type_key":"chemical_species"},"object":{"id":"84726d2b-9d3c-5b67-a13f-ebe1a172f7a8","slug":"tryptophan-niacin-apparent-conversion","display_name":"Apparent tryptophan-to-niacin conversion from urinary metabolites","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"dd60b289-0534-53e3-9afa-f6b397fc0086","stable_key":"1310afbd-6010-586e-805d-551d846da421:b6-met-rat-niacin-conversion-event","event_type":"observed_intervention","label":"B6 shortage reduced this dietary study's estimate of niacin production from tryptophan.","description":"Under niacin-free feeding, B6-free rats had lower apparent tryptophan-to-niacin conversion than rats receiving B6.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"769339cb-213b-559e-acc0-07ed00368b94","slug":"l-tryptophan","display_name":"L-Tryptophan","entity_type_key":"small_molecule"},"role":"dietary precursor","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"08c27a3f-552e-5c92-8688-321a9b64a0d6","slug":"nicotinamide","display_name":"Nicotinamide","entity_type_key":"small_molecule"},"role":"urinary conversion marker","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"9751fdb6-9b30-586f-b07a-79b8e2cd62dd","slug":"nicotinic-acid","display_name":"Nicotinic acid","entity_type_key":"small_molecule"},"role":"omitted dietary vitamin","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"c0beb226-8842-501f-a147-cac0d9fa7060","slug":"vitamin-b6","display_name":"Vitamin B6","entity_type_key":"chemical_species"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"84726d2b-9d3c-5b67-a13f-ebe1a172f7a8","slug":"tryptophan-niacin-apparent-conversion","display_name":"Apparent tryptophan-to-niacin conversion from urinary metabolites","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"Dietary B6 status affected apparent tryptophan-to-niacin conversion.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Young male Wistar rats; four controlled diets for 19 days","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Young male Wistar rats; 19-day diets; conversion contrast within niacin-free groups","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Apparent urinary conversion, not net synthesis or a human requirement.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin B6 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-b6","display_name":"Vitamin B6","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Rattus norvegicus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"B6 shortage reduced this dietary study's estimate of niacin production from tryptophan.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[b6-niacin-1995] Effects of Vitamin B6 Deficiency on the Conversion Ratio of Tryptophan to Niacin (1995). https://doi.org/10.1271/bbb.59.2060 DOI: 10.1271/bbb.59.2060","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Whole-animal dietary intake and urine","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"nutrient_deficiency","comparator":null,"unit":null,"notes":"Imported condition classification; 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four controlled diets for 19 days","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [b6-niacin-1995] Effects of Vitamin B6 Deficiency on the Conversion Ratio of Tryptophan to Niacin (1995). https://doi.org/10.1271/bbb.59.2060 DOI: 10.1271/bbb.59.2060","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"251773bb-16f5-5903-b135-db4a61d9dec4","stable_key":"import-1310afbd-6010-586e-805d-551d846da421","title":"Vitamin B6: mechanisms, deficiency and nutrient interactions (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":"ef0019b344b2219220f801a84d0d138ff6880c1be1a59540d9034bfa4334f61e","revision_id":"cac3555f-48af-5c52-a84e-add4482c87fb","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}