Component
Previtamin D2
Ergosterol photoproduct that thermally isomerizes to ergocalciferol.
2 recorded relationships. Experimental role, claim status and evidence remain attached to each record.
How nutrients influence it
Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.
Other things that act on it
Enzymes, hormones, genes, and other components with a recorded effect. These are not nutrients, so they do not count toward the arrows above. Each finding names the chapter that recorded it.
How nutrients reach it in more than one step
Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.
Tracing routes…
What it does
Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.
What it acts on
Previtamin D2 generated in irradiated mushrooms converted thermally to ergocalciferol; mushroom conversion was faster than in methanol in the compared preparations.
Experimental context and source evidence
- cross_nutrient
- false
- evidence_location
- Primary Results: Photoproduction of previtamin D2 and its conversion to vitamin D2; Figures 2-5.
- experimental_model
- Mushroom-versus-solution HPLC time course
- exposure
- Post-irradiation time course at 25 C; approximately half converted after 11.5 hours in mushrooms.
- limitations
- Matrix and temperature affect rate; no metabolic activation enzyme is implied.
- nutrient
- Vitamin D2 and D3 · Vitamin D2 and D3
- nutrient_topic
- Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin D2 and D3
- organism
- Agaricus bisporus
- plain_language
- The fungal photoproduct rearranges into vitamin D2.
- primary_references
- [keegan2013] Photobiology of vitamin D in mushrooms and its bioavailability in humans. (2013). https://pubmed.ncbi.nlm.nih.gov/24494050/ DOI: 10.4161/derm.23321
- tissue_or_cell_type
- mushroom tissue
Vitamin D2 and D3: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 151–164
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Mushroom-versus-solution HPLC time course · source_derived_draft · unverified_draft
### vd-act-previtamin-d2-isomerization Previtamin D2 generated in irradiated mushrooms converted thermally to ergocalciferol; mushroom conversion was faster than in methanol in the compared preparations. Condition category: normal nutrient_topic: Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect. plain_language: The fungal photoproduct rearranges into vitamin D2. organism: Agaricus bisporus tissue_or_cell_type: mushroom tissue experimental_model: Mushroom-versus-solution HPLC time course limitations: Matrix and temperature affect rate; no metabolic activation enzyme is implied. exposure: Post-irradiation time course at 25 C; approximately half converted after 11.5 hours in mushrooms. cross_nutrient: false evidence_location: Primary Results: Photoproduction of previtamin D2 and its conversion to vitamin D2; Figures 2-5. nutrient: Vitamin D2 and D3 [keegan2013] Photobiology of vitamin D in mushrooms and its bioavailability in humans. (2013). https://pubmed.ncbi.nlm.nih.gov/24494050/ DOI: 10.4161/derm.23321
Complete structured claim and evidence
What acts on it
Ultraviolet irradiation of white button mushrooms generated previtamin D2 from ergosterol, identified by chromatographic analysis.
Experimental context and source evidence
- cross_nutrient
- false
- evidence_location
- Primary Results: Photoproduction of previtamin D2 and its conversion to vitamin D2; Figures 2-5.
- experimental_model
- White button mushroom and ergosterol photochemistry
- exposure
- UV-irradiated preparations; protocol varied with irradiation experiment.
- limitations
- This is fungal/ex-vivo photochemistry; human skin D3 photochemistry is a separate route.
- nutrient
- Vitamin D2 and D3 · Vitamin D2 and D3
- nutrient_topic
- Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin D2 and D3
- organism
- Agaricus bisporus
- plain_language
- UV converts a fungal sterol into the precursor of vitamin D2.
- primary_references
- [keegan2013] Photobiology of vitamin D in mushrooms and its bioavailability in humans. (2013). https://pubmed.ncbi.nlm.nih.gov/24494050/ DOI: 10.4161/derm.23321
- tissue_or_cell_type
- mushroom tissue
Vitamin D2 and D3: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 136–149
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · White button mushroom and ergosterol photochemistry · source_derived_draft · unverified_draft
### vd-act-ergosterol-photoconversion Ultraviolet irradiation of white button mushrooms generated previtamin D2 from ergosterol, identified by chromatographic analysis. Condition category: normal nutrient_topic: Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect. plain_language: UV converts a fungal sterol into the precursor of vitamin D2. organism: Agaricus bisporus tissue_or_cell_type: mushroom tissue experimental_model: White button mushroom and ergosterol photochemistry limitations: This is fungal/ex-vivo photochemistry; human skin D3 photochemistry is a separate route. exposure: UV-irradiated preparations; protocol varied with irradiation experiment. cross_nutrient: false evidence_location: Primary Results: Photoproduction of previtamin D2 and its conversion to vitamin D2; Figures 2-5. nutrient: Vitamin D2 and D3 [keegan2013] Photobiology of vitamin D in mushrooms and its bioavailability in humans. (2013). https://pubmed.ncbi.nlm.nih.gov/24494050/ DOI: 10.4161/derm.23321
Complete structured claim and evidence
The events it takes part in
A mechanism often involves more than two components. These are the full events, with every participant and its role.
Situations it appears in
Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.
In the sources
Preserved passages that mention this component, quoted exactly. Open one to read it in context.
Open hypotheses
Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.
This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.