{"id":"a3f5c12a-7ed8-5f62-a957-4abe60699c4e","stable_key":"33bef151-bdc7-5892-aff6-0345ab149739:nsk-sd-is-labile-below-ph-5","predicate":"inactivates","statement":"In product testing at 25 C, NSK-SD retained activity for 24 h between pH 5.5 and 10 but was labile below pH 5.0.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"e67ae538-91dc-51f2-b0f7-922e60a4ddd3","mechanism_event_label":"In product testing at 25 C, NSK-SD retained activity for 24 h between pH 5.5 and 10 but was labile below pH 5.0.","subject":{"id":"a9c733d2-c6d6-55df-a70d-9c6668954e8f","slug":"acidity-below-ph-5","display_name":"Acidity below pH 5","entity_type_key":"cellular_process"},"object":{"id":"6b03a125-209a-5060-8b35-ec9e0e54033c","slug":"nattokinase","display_name":"Nattokinase / subtilisin NAT","entity_type_key":"peptide"},"evidence_count":1,"mechanism_event":{"id":"e67ae538-91dc-51f2-b0f7-922e60a4ddd3","stable_key":"33bef151-bdc7-5892-aff6-0345ab149739:nsk-sd-is-labile-below-ph-5-event","event_type":"biochemical_relationship","label":"In product testing at 25 C, NSK-SD retained activity for 24 h between pH 5.5 and 10 but was labile below pH 5.0.","description":"25% aqueous product solution at 25 C","status":"provisional","compartment":null,"participants":[{"entity":{"id":"a9c733d2-c6d6-55df-a70d-9c6668954e8f","slug":"acidity-below-ph-5","display_name":"Acidity below pH 5","entity_type_key":"cellular_process"},"role":"acting component","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"6b03a125-209a-5060-8b35-ec9e0e54033c","slug":"nattokinase","display_name":"Nattokinase / subtilisin NAT","entity_type_key":"peptide"},"role":"component the finding is about","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""}]},"contexts":[{"dimension":"duration","value_text":"24 h","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_access","value_text":"EFSA Journal opinion retrieved and read in full during this curation. Quoted figures are from the opinion text and its specification tables.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"Product stability testing","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"NSK-SD","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"A product stability measurement, not a human gastric-survival measurement: fasting gastric pH is well below 5.0. An applicant assay of the softgel at pH 2.0 mimicking gastric fluid was submitted to EFSA, but the opinion records only that the results were provided, not what they were.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"organism","value_text":"Product stability testing","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"In product testing at 25 C, NSK-SD retained activity for 24 h between pH 5.5 and 10 but was labile below pH 5.0.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"Safety of fermented soybean extract NSK-SD as a novel food. (2016) DOI: 10.2903/j.efsa.2016.4541 Not indexed in PubMed.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"route","value_text":"In vitro","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue","value_text":"25% aqueous product solution at 25 C","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"3f605bc8-e384-594e-b578-418f5612933c","evidence_kind":"source_excerpt","locator":"Lines 1368-1368","start_line":1368,"end_line":1368,"excerpt":"In product testing at 25 C, NSK-SD retained activity for 24 h between pH 5.5 and 10 but was labile below pH 5.0.","model_system":"Product stability testing","directness":"reported_statement","verification_status":"source_derived_draft","notes":"","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"41cb127c-1c23-53aa-b7d0-5ec7f6fa3c99","stable_key":"import-33bef151-bdc7-5892-aff6-0345ab149739","title":"Nattokinase: what the purified enzyme cleaves, what survives being eaten, and the gap between the two (2026-09-23)","document_type":"imported_text","citation_label":"Original AI-assisted curation built from a supplied entity-first document of 105 entities and 129 claims. Every reference in that document was resolved against live PubMed with its abstract read and its DOI cross-checked on 2026-09-23, and the EFSA novel-food opinion was retrieved and read in full. That check corrected two PMIDs that pointed at unrelated papers, two DOIs, and two papers recorded as carrying no erratum that do carry one; it also reversed three findings the supplied document had stated backwards. Two papers carry a published correction, recorded as such and not as a retraction. Three sources are not indexed in PubMed and are cited by what they have. Laboratory lineages are recorded, so the four papers from one group, the three from another and the two readings of a single applicant dossier cannot be counted as separate lines of support. Study-specific doses, units, populations and limitations retained; activity units are never converted between systems. Not publisher full text.","file_path":"","sha256":"34fc46e0e849d06bfa13cb099a79b50679dd6fd0de8a5a0575326afdde3259c1","revision_id":"efd063e6-e982-5f6e-a4b8-6f2ffe4185ce","review_status":"unverified_draft","notes":""}}],"relations":[{"id":"e01d94e9-c4b0-5875-8367-cc9b36aafaf1","relation_type":"qualifies","notes":"The product loses activity below pH 5.0 and fasting gastric pH is well below that, so what reaches the intestine need not be the molecule that was swallowed.","source_claim_id":"a3f5c12a-7ed8-5f62-a957-4abe60699c4e","source_claim_key":"33bef151-bdc7-5892-aff6-0345ab149739:nsk-sd-is-labile-below-ph-5","source_statement":"In product testing at 25 C, NSK-SD retained activity for 24 h between pH 5.5 and 10 but was labile below pH 5.0.","target_claim_id":"d5dcd9d3-e490-56a1-8b8d-5d4b8255eec4","target_claim_key":"33bef151-bdc7-5892-aff6-0345ab149739:a-single-oral-dose-produces-plasma-immunoreactivity","target_statement":"A single 2,000 FU oral NSK-SD dose produced anti-nattokinase immunoreactivity in serum that rose significantly from baseline between 2 and 24 h and peaked at about 13.3 +/- 2.5 h."}],"conflicts":[],"corrections":[],"research":null}