{"id":"f7731996-d1f2-521a-8a6d-77164ffe6009","stable_key":"7484635e-cc8f-5cd6-a978-6dc5775a7db5:berberine-microbial-reduction","predicate":"reduces_to_dihydroberberine","statement":"Gut bacterial nitroreductases converted berberine to dihydroberberine.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"36fbe3b5-4d7f-5850-8595-59c6ca693226","mechanism_event_label":"Gut microbes can change the chemical form before it is absorbed.","subject":{"id":"ba53851b-1844-535c-8894-4c450e52b12c","slug":"bacterial-nitroreductases","display_name":"Gut bacterial nitroreductases, species and isoform not resolved","entity_type_key":"protein_family"},"object":{"id":"7bbe0633-b2f1-510f-adc0-3c4d0ddad05d","slug":"berberine","display_name":"Berberine","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"36fbe3b5-4d7f-5850-8595-59c6ca693226","stable_key":"7484635e-cc8f-5cd6-a978-6dc5775a7db5:berberine-microbial-reduction-event","event_type":"biochemical_relationship","label":"Gut microbes can change the chemical form before it is absorbed.","description":"Gut bacterial nitroreductases converted berberine to dihydroberberine.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"ce99dfde-ad37-5f27-8e17-72892ec8a627","slug":"dihydroberberine","display_name":"Dihydroberberine","entity_type_key":"small_molecule"},"role":"product","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"ba53851b-1844-535c-8894-4c450e52b12c","slug":"bacterial-nitroreductases","display_name":"Gut bacterial nitroreductases, species and isoform not resolved","entity_type_key":"protein_family"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"7bbe0633-b2f1-510f-adc0-3c4d0ddad05d","slug":"berberine","display_name":"Berberine","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"evidence_span","value_text":"{\"source_cache\": \"artifacts/berberine-research/26174047.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"17b12fa4d334225782db565c20fc34051522dafd77be442782aa82bd1ef34c9e\", \"start_char\": 0, \"end_char\": 1403, \"text_sha256\": \"17b12fa4d334225782db565c20fc34051522dafd77be442782aa82bd1ef34c9e\"}","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Bacterial enzyme, intestinal tissue, absorption and antibiotic-depletion experiments","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Oral berberine, dihydroberberine and antibiotic pretreatment","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Animal absorption difference is not a human bioavailability multiplier. Nitroreductases are unresolved bacterial enzyme families; no nitrogen-removal or vitamin-depletion mechanism inferred.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Berberine research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"berberine","display_name":"Berberine","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Gut bacteria and rodents including KK-Ay mice","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Gut microbes can change the chemical form before it is absorbed.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[berberine-p26174047] Transforming berberine into its intestine-absorbable form by the gut microbiota. (2015). https://pubmed.ncbi.nlm.nih.gov/26174047/ DOI: 10.1038/srep12155","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Gut lumen, intestinal tissue and circulation","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"01ef8629-0556-5325-9e73-0d5826ef38be","evidence_kind":"source_excerpt","locator":"Lines 142-153","start_line":142,"end_line":153,"excerpt":"### berberine-microbial-reduction\nGut bacterial nitroreductases converted berberine to dihydroberberine.\nCondition category: normal\nnutrient_topic: Berberine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Gut microbes can change the chemical form before it is absorbed.\norganism: Gut bacteria and rodents including KK-Ay mice\ntissue_or_cell_type: Gut lumen, intestinal tissue and circulation\nexperimental_model: Bacterial enzyme, intestinal tissue, absorption and antibiotic-depletion experiments\nlimitations: Animal absorption difference is not a human bioavailability multiplier. Nitroreductases are unresolved bacterial enzyme families; no nitrogen-removal or vitamin-depletion mechanism inferred.\nexposure: Oral berberine, dihydroberberine and antibiotic pretreatment\nevidence_span: {\"source_cache\": \"artifacts/berberine-research/26174047.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"17b12fa4d334225782db565c20fc34051522dafd77be442782aa82bd1ef34c9e\", \"start_char\": 0, \"end_char\": 1403, \"text_sha256\": \"17b12fa4d334225782db565c20fc34051522dafd77be442782aa82bd1ef34c9e\"}\n[berberine-p26174047] Transforming berberine into its intestine-absorbable form by the gut microbiota. (2015). https://pubmed.ncbi.nlm.nih.gov/26174047/ DOI: 10.1038/srep12155","model_system":"Bacterial enzyme, intestinal tissue, absorption and antibiotic-depletion experiments","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [berberine-p26174047] Transforming berberine into its intestine-absorbable form by the gut microbiota. (2015). https://pubmed.ncbi.nlm.nih.gov/26174047/ DOI: 10.1038/srep12155","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"9bb61e1d-e5cf-5b05-a9ca-409291f7a313","stable_key":"import-7484635e-cc8f-5cd6-a978-6dc5775a7db5","title":"Berberine: metabolism, nutrient connections and drug 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":"2f376a035ae79c93e62e2ea4a8d5385643bf16553f108d12b6a80c89e6d41f4c","revision_id":"2a099429-1c4a-55be-aa2c-0565d08bda80","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}