meso-Zeaxanthin / (3R,3-prime-S)-zeaxanthin

evidence_span

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experimental_model

Comparative recombinant enzyme and cell experiments

exposure

Low-temperature expression and detergent variation

limitations

Conserved activity does not demonstrate identical rates across species or diets.

nutrient_topic

Lutein research collection; topical membership is not evidence of a direct dietary effect. · Lutein

organism

Primate and murine BCO2

plain_language

How the protein was prepared changed the measured activity.

primary_references

[lutein-p26307071] Characterization of the Role of β-Carotene 9,10-Dioxygenase in Macular Pigment Metabolism. (2015). https://pubmed.ncbi.nlm.nih.gov/26307071/ DOI: 10.1074/jbc.m115.668822

tissue_or_cell_type

Protein preparations and human hepatic cell line

Lutein: metabolism, signaling and nutrient connections (2026-09-17) · lines 320–331

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Comparative recombinant enzyme and cell experiments · source_derived_draft · unverified_draft

### lutein-bco2-method-dependence Expression temperature and detergent choice affected recombinant BCO2 binding and xanthophyll turnover, including meso-zeaxanthin. Condition category: normal nutrient_topic: Lutein research collection; topical membership is not evidence of a direct dietary effect. plain_language: How the protein was prepared changed the measured activity. organism: Primate and murine BCO2 tissue_or_cell_type: Protein preparations and human hepatic cell line experimental_model: Comparative recombinant enzyme and cell experiments limitations: Conserved activity does not demonstrate identical rates across species or diets. exposure: Low-temperature expression and detergent variation evidence_span: {"source_cache": "artifacts/lutein-research/26307071.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6b225e90d2edb66a12583bcdaefb8247cf57c26dffd4f02a1a189907c6f97916", "start_char": 0, "end_char": 1495, "text_sha256": "6b225e90d2edb66a12583bcdaefb8247cf57c26dffd4f02a1a189907c6f97916"} [lutein-p26307071] Characterization of the Role of β-Carotene 9,10-Dioxygenase in Macular Pigment Metabolism. (2015). https://pubmed.ncbi.nlm.nih.gov/26307071/ DOI: 10.1074/jbc.m115.668822

evidence_span

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experimental_model

Overexpression, developmental expression and pharmacological inhibition

exposure

RPE65 expression with lutein; inhibitor experiments in developing chicken eye

limitations

Cell and animal evidence; docking near iron is not a human iron-supplementation experiment.

nutrient_topic

Lutein research collection; topical membership is not evidence of a direct dietary effect. · Lutein

organism

Human/chicken proteins in cells and chicken embryos

plain_language

The conversion was also observed with the chicken enzyme.

primary_references

[lutein-p28874556] RPE65 has an additional function as the lutein to meso-zeaxanthin isomerase in the vertebrate eye. (2017). https://pubmed.ncbi.nlm.nih.gov/28874556/ DOI: 10.1073/pnas.1706332114

tissue_or_cell_type

Cultured cells and embryonic RPE/choroid

Lutein: metabolism, signaling and nutrient connections (2026-09-17) · lines 164–175

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Overexpression, developmental expression and pharmacological inhibition · source_derived_draft · unverified_draft

### lutein-chicken-rpe65-isomerase Chicken RPE65 overexpression supported meso-zeaxanthin production from lutein. Condition category: normal nutrient_topic: Lutein research collection; topical membership is not evidence of a direct dietary effect. plain_language: The conversion was also observed with the chicken enzyme. organism: Human/chicken proteins in cells and chicken embryos tissue_or_cell_type: Cultured cells and embryonic RPE/choroid experimental_model: Overexpression, developmental expression and pharmacological inhibition limitations: Cell and animal evidence; docking near iron is not a human iron-supplementation experiment. exposure: RPE65 expression with lutein; inhibitor experiments in developing chicken eye evidence_span: {"source_cache": "artifacts/lutein-research/28874556.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "240bde60bb175fdfd5f556b9f2f7aab97f5d5b03e9640160418c34c74194d8c9", "start_char": 0, "end_char": 1679, "text_sha256": "240bde60bb175fdfd5f556b9f2f7aab97f5d5b03e9640160418c34c74194d8c9"} [lutein-p28874556] RPE65 has an additional function as the lutein to meso-zeaxanthin isomerase in the vertebrate eye. (2017). https://pubmed.ncbi.nlm.nih.gov/28874556/ DOI: 10.1073/pnas.1706332114

evidence_span

{"source_cache": "artifacts/lutein-research/28874556.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "240bde60bb175fdfd5f556b9f2f7aab97f5d5b03e9640160418c34c74194d8c9", "start_char": 0, "end_char": 1679, "text_sha256": "240bde60bb175fdfd5f556b9f2f7aab97f5d5b03e9640160418c34c74194d8c9"}

experimental_model

Overexpression, developmental expression and pharmacological inhibition

exposure

RPE65 expression with lutein; inhibitor experiments in developing chicken eye

limitations

Cell and animal evidence; docking near iron is not a human iron-supplementation experiment.

nutrient_topic

Lutein research collection; topical membership is not evidence of a direct dietary effect. · Lutein

organism

Human/chicken proteins in cells and chicken embryos

plain_language

The visual-cycle enzyme can also rearrange lutein.

primary_references

[lutein-p28874556] RPE65 has an additional function as the lutein to meso-zeaxanthin isomerase in the vertebrate eye. (2017). https://pubmed.ncbi.nlm.nih.gov/28874556/ DOI: 10.1073/pnas.1706332114

tissue_or_cell_type

Cultured cells and embryonic RPE/choroid

Lutein: metabolism, signaling and nutrient connections (2026-09-17) · lines 151–162

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Overexpression, developmental expression and pharmacological inhibition · source_derived_draft · unverified_draft

### lutein-human-rpe65-isomerase Overexpressed human RPE65 supported conversion of lutein into meso-zeaxanthin in cultured cells. Condition category: normal nutrient_topic: Lutein research collection; topical membership is not evidence of a direct dietary effect. plain_language: The visual-cycle enzyme can also rearrange lutein. organism: Human/chicken proteins in cells and chicken embryos tissue_or_cell_type: Cultured cells and embryonic RPE/choroid experimental_model: Overexpression, developmental expression and pharmacological inhibition limitations: Cell and animal evidence; docking near iron is not a human iron-supplementation experiment. exposure: RPE65 expression with lutein; inhibitor experiments in developing chicken eye evidence_span: {"source_cache": "artifacts/lutein-research/28874556.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "240bde60bb175fdfd5f556b9f2f7aab97f5d5b03e9640160418c34c74194d8c9", "start_char": 0, "end_char": 1679, "text_sha256": "240bde60bb175fdfd5f556b9f2f7aab97f5d5b03e9640160418c34c74194d8c9"} [lutein-p28874556] RPE65 has an additional function as the lutein to meso-zeaxanthin isomerase in the vertebrate eye. (2017). https://pubmed.ncbi.nlm.nih.gov/28874556/ DOI: 10.1073/pnas.1706332114

evidence_span

{"source_cache": "artifacts/lutein-research/41415389.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "b4eb5b9290310947be962df7dae42190e5afa6ffd726e869cb842d7f7ed15a41", "start_char": 0, "end_char": 1304, "text_sha256": "b4eb5b9290310947be962df7dae42190e5afa6ffd726e869cb842d7f7ed15a41"}

experimental_model

Cultured-cell enzyme expression, mutagenesis and structural modeling

exposure

Lutein substrate; E148Q substitution; binding-protein coexpression

limitations

Proposed radical transition state remains a mechanistic interpretation, not directly observed chemistry.

nutrient_topic

Lutein research collection; topical membership is not evidence of a direct dietary effect. · Lutein

organism

Human, chicken and mouse RPE65

plain_language

Enzyme capacity and whole-tissue pigment accumulation are different.

primary_references

[lutein-p41415389] Mechanism of Lutein to meso-Zeaxanthin Isomerization by RPE65 Catalysis. (2025). https://pubmed.ncbi.nlm.nih.gov/41415389/ DOI: 10.64898/2025.12.10.693550

tissue_or_cell_type

Cultured cells and molecular models

Lutein: metabolism, signaling and nutrient connections (2026-09-17) · lines 190–201

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cultured-cell enzyme expression, mutagenesis and structural modeling · source_derived_draft · unverified_draft

### lutein-mouse-rpe65-isomerase Mouse RPE65 supported lutein isomerization in cultured cells despite mice not normally concentrating meso-zeaxanthin in the eye. Condition category: normal nutrient_topic: Lutein research collection; topical membership is not evidence of a direct dietary effect. plain_language: Enzyme capacity and whole-tissue pigment accumulation are different. organism: Human, chicken and mouse RPE65 tissue_or_cell_type: Cultured cells and molecular models experimental_model: Cultured-cell enzyme expression, mutagenesis and structural modeling limitations: Proposed radical transition state remains a mechanistic interpretation, not directly observed chemistry. exposure: Lutein substrate; E148Q substitution; binding-protein coexpression evidence_span: {"source_cache": "artifacts/lutein-research/41415389.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "b4eb5b9290310947be962df7dae42190e5afa6ffd726e869cb842d7f7ed15a41", "start_char": 0, "end_char": 1304, "text_sha256": "b4eb5b9290310947be962df7dae42190e5afa6ffd726e869cb842d7f7ed15a41"} [lutein-p41415389] Mechanism of Lutein to meso-Zeaxanthin Isomerization by RPE65 Catalysis. (2025). https://pubmed.ncbi.nlm.nih.gov/41415389/ DOI: 10.64898/2025.12.10.693550

evidence_span

{"source_cache": "artifacts/lutein-research/27538825.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "1db014221931676349f15dc3c5138fba122417fb49fec5de481594c72b0596f3", "start_char": 0, "end_char": 1346, "text_sha256": "1db014221931676349f15dc3c5138fba122417fb49fec5de481594c72b0596f3"}

experimental_model

Carotenoid delivery using isolated human lipoproteins

exposure

Carotenoid-loaded LDL versus HDL

limitations

Cell delivery ranking is not identical to circulating carriage fractions or the WHAM-chicken phenotype.

nutrient_topic

Lutein research collection; topical membership is not evidence of a direct dietary effect. · Lutein

organism

Human ARPE-19 cells

plain_language

Uptake alone did not reproduce the separate RPE65 overexpression result.

primary_references

[lutein-p27538825] Mechanisms of selective delivery of xanthophylls to retinal pigment epithelial cells by human lipoproteins. (2016). https://pubmed.ncbi.nlm.nih.gov/27538825/ DOI: 10.1194/jlr.m070193

tissue_or_cell_type

Retinal pigment epithelial model

Lutein: metabolism, signaling and nutrient connections (2026-09-17) · lines 658–669

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Carotenoid delivery using isolated human lipoproteins · source_derived_draft · unverified_draft

### lutein-rpe-isomerization-null This ARPE-19 delivery experiment detected no lutein conversion to meso-zeaxanthin. Condition category: normal nutrient_topic: Lutein research collection; topical membership is not evidence of a direct dietary effect. plain_language: Uptake alone did not reproduce the separate RPE65 overexpression result. organism: Human ARPE-19 cells tissue_or_cell_type: Retinal pigment epithelial model experimental_model: Carotenoid delivery using isolated human lipoproteins limitations: Cell delivery ranking is not identical to circulating carriage fractions or the WHAM-chicken phenotype. exposure: Carotenoid-loaded LDL versus HDL evidence_span: {"source_cache": "artifacts/lutein-research/27538825.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "1db014221931676349f15dc3c5138fba122417fb49fec5de481594c72b0596f3", "start_char": 0, "end_char": 1346, "text_sha256": "1db014221931676349f15dc3c5138fba122417fb49fec5de481594c72b0596f3"} [lutein-p27538825] Mechanisms of selective delivery of xanthophylls to retinal pigment epithelial cells by human lipoproteins. (2016). https://pubmed.ncbi.nlm.nih.gov/27538825/ DOI: 10.1194/jlr.m070193

evidence_span

{"source_cache": "artifacts/zeaxanthin-research/15355982.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6365b1d54aafda71be4dbf6c8e5252fa6ce0af3b808d9af6fe07c37ae188ea92", "start_char": 0, "end_char": 1907, "text_sha256": "6365b1d54aafda71be4dbf6c8e5252fa6ce0af3b808d9af6fe07c37ae188ea92"}

experimental_model

Human macular protein purification and recombinant binding

exposure

Equilibrium binding and immunocytochemistry

limitations

Binding affinity is assay-specific and does not quantify uptake or clinical benefit.

nutrient_topic

Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. · Dietary (3R,3-prime-R)-zeaxanthin

organism

Human tissue/proteins

plain_language

The stereoisomer also has a binding site.

primary_references

[zeaxanthin-p15355982] Identification and characterization of a Pi isoform of glutathione S-transferase (GSTP1) as a zeaxanthin-binding protein in the macula of the human eye. (2004). https://pubmed.ncbi.nlm.nih.gov/15355982/ DOI: 10.1074/jbc.m405334200

tissue_or_cell_type

Macula and purified proteins

Zeaxanthin: metabolism, signaling and nutrient connections (2026-09-17) · lines 223–234

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Human macular protein purification and recombinant binding · source_derived_draft · unverified_draft

### zeaxanthin-gstp1-meso GSTP1 bound meso-zeaxanthin with apparent Kd 0.52 micromolar. Condition category: normal nutrient_topic: Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. plain_language: The stereoisomer also has a binding site. organism: Human tissue/proteins tissue_or_cell_type: Macula and purified proteins experimental_model: Human macular protein purification and recombinant binding limitations: Binding affinity is assay-specific and does not quantify uptake or clinical benefit. exposure: Equilibrium binding and immunocytochemistry evidence_span: {"source_cache": "artifacts/zeaxanthin-research/15355982.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6365b1d54aafda71be4dbf6c8e5252fa6ce0af3b808d9af6fe07c37ae188ea92", "start_char": 0, "end_char": 1907, "text_sha256": "6365b1d54aafda71be4dbf6c8e5252fa6ce0af3b808d9af6fe07c37ae188ea92"} [zeaxanthin-p15355982] Identification and characterization of a Pi isoform of glutathione S-transferase (GSTP1) as a zeaxanthin-binding protein in the macula of the human eye. (2004). https://pubmed.ncbi.nlm.nih.gov/15355982/ DOI: 10.1074/jbc.m405334200

evidence_span

{"source_cache": "artifacts/zeaxanthin-research/15137922.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6410a0f5d52cf32390f90f59a7b17d2340a889f888836129f8a93482ca055be0", "start_char": 0, "end_char": 1847, "text_sha256": "6410a0f5d52cf32390f90f59a7b17d2340a889f888836129f8a93482ca055be0"}

experimental_model

Randomized single-blind crossover meal trial

exposure

5 mg free zeaxanthin equivalents as free pigment or dipalmitate in yoghurt/breakfast; 24 h sampling

limitations

Meal- and formulation-specific response; no proof of disease prevention or an optimal universal formulation.

nutrient_topic

Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. · Dietary (3R,3-prime-R)-zeaxanthin

organism

12 volunteers

plain_language

The study did not show rapid conversion of dietary zeaxanthin into meso-zeaxanthin.

primary_references

[zeaxanthin-p15137922] Comparison of plasma responses in human subjects after the ingestion of 3R,3R'-zeaxanthin dipalmitate from wolfberry (Lycium barbarum) and non-esterified 3R,3R'-zeaxanthin using chiral high-performance liquid chromatography. (2004). https://pubmed.ncbi.nlm.nih.gov/15137922/ DOI: 10.1079/bjn20041105

tissue_or_cell_type

Plasma response

Zeaxanthin: metabolism, signaling and nutrient connections (2026-09-17) · lines 808–819

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Randomized single-blind crossover meal trial · source_derived_draft · unverified_draft

### zeaxanthin-human-meso-null No meso-zeaxanthin formation was detected over the trial sampling period. Condition category: normal nutrient_topic: Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. plain_language: The study did not show rapid conversion of dietary zeaxanthin into meso-zeaxanthin. organism: 12 volunteers tissue_or_cell_type: Plasma response experimental_model: Randomized single-blind crossover meal trial limitations: Meal- and formulation-specific response; no proof of disease prevention or an optimal universal formulation. exposure: 5 mg free zeaxanthin equivalents as free pigment or dipalmitate in yoghurt/breakfast; 24 h sampling evidence_span: {"source_cache": "artifacts/zeaxanthin-research/15137922.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6410a0f5d52cf32390f90f59a7b17d2340a889f888836129f8a93482ca055be0", "start_char": 0, "end_char": 1847, "text_sha256": "6410a0f5d52cf32390f90f59a7b17d2340a889f888836129f8a93482ca055be0"} [zeaxanthin-p15137922] Comparison of plasma responses in human subjects after the ingestion of 3R,3R'-zeaxanthin dipalmitate from wolfberry (Lycium barbarum) and non-esterified 3R,3R'-zeaxanthin using chiral high-performance liquid chromatography. (2004). https://pubmed.ncbi.nlm.nih.gov/15137922/ DOI: 10.1079/bjn20041105

evidence_span

{"source_cache": "artifacts/lutein-research/20678467.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "aaf88f567941ed16adb101981a218960bbd8ae3cfe0919868de63462e7c7be01", "start_char": 0, "end_char": 989, "text_sha256": "aaf88f567941ed16adb101981a218960bbd8ae3cfe0919868de63462e7c7be01"}

experimental_model

EPR of donor eye tissue and solution quenching assays

exposure

White-light challenge and equal-total-concentration carotenoid comparisons

limitations

Solution mixture effects do not establish an optimal oral ratio or clinical benefit; exogenous pigment addition differs from delivery in a living eye.

nutrient_topic

Lutein research collection; topical membership is not evidence of a direct dietary effect. · Lutein

organism

Postmortem human tissue and cell-free systems

plain_language

The three pigments worked better together in this solution experiment.

primary_references

[lutein-p20678467] Studies on the singlet oxygen scavenging mechanism of human macular pigment. (2010). https://pubmed.ncbi.nlm.nih.gov/20678467/ DOI: 10.1016/j.abb.2010.07.024

tissue_or_cell_type

Macula, RPE/choroid and carotenoid solutions

Lutein: metabolism, signaling and nutrient connections (2026-09-17) · lines 229–240

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · EPR of donor eye tissue and solution quenching assays · source_derived_draft · unverified_draft

### lutein-mixture-quenching The equal-ratio meso-zeaxanthin, zeaxanthin and lutein mixture quenched more singlet oxygen than each individual pigment at the same total concentration. Condition category: normal nutrient_topic: Lutein research collection; topical membership is not evidence of a direct dietary effect. plain_language: The three pigments worked better together in this solution experiment. organism: Postmortem human tissue and cell-free systems tissue_or_cell_type: Macula, RPE/choroid and carotenoid solutions experimental_model: EPR of donor eye tissue and solution quenching assays limitations: Solution mixture effects do not establish an optimal oral ratio or clinical benefit; exogenous pigment addition differs from delivery in a living eye. exposure: White-light challenge and equal-total-concentration carotenoid comparisons evidence_span: {"source_cache": "artifacts/lutein-research/20678467.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "aaf88f567941ed16adb101981a218960bbd8ae3cfe0919868de63462e7c7be01", "start_char": 0, "end_char": 989, "text_sha256": "aaf88f567941ed16adb101981a218960bbd8ae3cfe0919868de63462e7c7be01"} [lutein-p20678467] Studies on the singlet oxygen scavenging mechanism of human macular pigment. (2010). https://pubmed.ncbi.nlm.nih.gov/20678467/ DOI: 10.1016/j.abb.2010.07.024

availability_state

machinery_impairment Imported condition classification; unverified.

evidence_span

{"source_cache": "artifacts/lutein-research/28874556.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "240bde60bb175fdfd5f556b9f2f7aab97f5d5b03e9640160418c34c74194d8c9", "start_char": 0, "end_char": 1679, "text_sha256": "240bde60bb175fdfd5f556b9f2f7aab97f5d5b03e9640160418c34c74194d8c9"}

experimental_model

Overexpression, developmental expression and pharmacological inhibition

exposure

RPE65 expression with lutein; inhibitor experiments in developing chicken eye

limitations

Cell and animal evidence; docking near iron is not a human iron-supplementation experiment.

nutrient_topic

Lutein research collection; topical membership is not evidence of a direct dietary effect. · Lutein

organism

Human/chicken proteins in cells and chicken embryos

plain_language

An enzyme block reduced pigment production despite the distinct dietary precursor.

primary_references

[lutein-p28874556] RPE65 has an additional function as the lutein to meso-zeaxanthin isomerase in the vertebrate eye. (2017). https://pubmed.ncbi.nlm.nih.gov/28874556/ DOI: 10.1073/pnas.1706332114

tissue_or_cell_type

Cultured cells and embryonic RPE/choroid

trigger_kind

machinery_impairment Imported condition classification; unverified.

Lutein: metabolism, signaling and nutrient connections (2026-09-17) · lines 177–188

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Overexpression, developmental expression and pharmacological inhibition · source_derived_draft · unverified_draft

### lutein-rpe65-inhibition RPE65 inhibition reduced meso-zeaxanthin biosynthesis during chicken eye development. Condition category: machinery_impairment nutrient_topic: Lutein research collection; topical membership is not evidence of a direct dietary effect. plain_language: An enzyme block reduced pigment production despite the distinct dietary precursor. organism: Human/chicken proteins in cells and chicken embryos tissue_or_cell_type: Cultured cells and embryonic RPE/choroid experimental_model: Overexpression, developmental expression and pharmacological inhibition limitations: Cell and animal evidence; docking near iron is not a human iron-supplementation experiment. exposure: RPE65 expression with lutein; inhibitor experiments in developing chicken eye evidence_span: {"source_cache": "artifacts/lutein-research/28874556.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "240bde60bb175fdfd5f556b9f2f7aab97f5d5b03e9640160418c34c74194d8c9", "start_char": 0, "end_char": 1679, "text_sha256": "240bde60bb175fdfd5f556b9f2f7aab97f5d5b03e9640160418c34c74194d8c9"} [lutein-p28874556] RPE65 has an additional function as the lutein to meso-zeaxanthin isomerase in the vertebrate eye. (2017). https://pubmed.ncbi.nlm.nih.gov/28874556/ DOI: 10.1073/pnas.1706332114

evidence_span

{"source_cache": "artifacts/zeaxanthin-research/15949677.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194", "start_char": 0, "end_char": 1404, "text_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194"}

experimental_model

Lipid-peroxyl radical challenge in liposomes

exposure

AAPH or AMVN challenge; dietary and meso zeaxanthin

limitations

Protein-associated antioxidant synergy is demonstrated in this assay, not a clinical supplement combination.

nutrient_topic

Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. · Dietary (3R,3-prime-R)-zeaxanthin

organism

Cell-free system with human GSTP1

plain_language

This binding-related effect persisted without glutathione.

primary_references

[zeaxanthin-p15949677] Synergistic effects of zeaxanthin and its binding protein in the prevention of lipid membrane oxidation. (2005). https://pubmed.ncbi.nlm.nih.gov/15949677/ DOI: 10.1016/j.bbadis.2005.02.002

tissue_or_cell_type

Egg-yolk phosphatidylcholine liposomes

Zeaxanthin: metabolism, signaling and nutrient connections (2026-09-17) · lines 288–299

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Lipid-peroxyl radical challenge in liposomes · source_derived_draft · unverified_draft

### zeaxanthin-gsh-independent The GSTP1–zeaxanthin protective effect did not require glutathione in this liposome experiment. Condition category: normal nutrient_topic: Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. plain_language: This binding-related effect persisted without glutathione. organism: Cell-free system with human GSTP1 tissue_or_cell_type: Egg-yolk phosphatidylcholine liposomes experimental_model: Lipid-peroxyl radical challenge in liposomes limitations: Protein-associated antioxidant synergy is demonstrated in this assay, not a clinical supplement combination. exposure: AAPH or AMVN challenge; dietary and meso zeaxanthin evidence_span: {"source_cache": "artifacts/zeaxanthin-research/15949677.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194", "start_char": 0, "end_char": 1404, "text_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194"} [zeaxanthin-p15949677] Synergistic effects of zeaxanthin and its binding protein in the prevention of lipid membrane oxidation. (2005). https://pubmed.ncbi.nlm.nih.gov/15949677/ DOI: 10.1016/j.bbadis.2005.02.002

evidence_span

{"source_cache": "artifacts/zeaxanthin-research/15949677.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194", "start_char": 0, "end_char": 1404, "text_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194"}

experimental_model

Lipid-peroxyl radical challenge in liposomes

exposure

AAPH or AMVN challenge; dietary and meso zeaxanthin

limitations

Protein-associated antioxidant synergy is demonstrated in this assay, not a clinical supplement combination.

nutrient_topic

Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. · Dietary (3R,3-prime-R)-zeaxanthin

organism

Cell-free system with human GSTP1

plain_language

The protein helped preserve the pigments during oxidation.

primary_references

[zeaxanthin-p15949677] Synergistic effects of zeaxanthin and its binding protein in the prevention of lipid membrane oxidation. (2005). https://pubmed.ncbi.nlm.nih.gov/15949677/ DOI: 10.1016/j.bbadis.2005.02.002

tissue_or_cell_type

Egg-yolk phosphatidylcholine liposomes

Zeaxanthin: metabolism, signaling and nutrient connections (2026-09-17) · lines 275–286

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Lipid-peroxyl radical challenge in liposomes · source_derived_draft · unverified_draft

### zeaxanthin-gstp1-stability GSTP1 association increased resistance of zeaxanthin diastereomers to chemical degradation. Condition category: normal nutrient_topic: Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. plain_language: The protein helped preserve the pigments during oxidation. organism: Cell-free system with human GSTP1 tissue_or_cell_type: Egg-yolk phosphatidylcholine liposomes experimental_model: Lipid-peroxyl radical challenge in liposomes limitations: Protein-associated antioxidant synergy is demonstrated in this assay, not a clinical supplement combination. exposure: AAPH or AMVN challenge; dietary and meso zeaxanthin evidence_span: {"source_cache": "artifacts/zeaxanthin-research/15949677.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194", "start_char": 0, "end_char": 1404, "text_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194"} [zeaxanthin-p15949677] Synergistic effects of zeaxanthin and its binding protein in the prevention of lipid membrane oxidation. (2005). https://pubmed.ncbi.nlm.nih.gov/15949677/ DOI: 10.1016/j.bbadis.2005.02.002

evidence_span

{"source_cache": "artifacts/zeaxanthin-research/15949677.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194", "start_char": 0, "end_char": 1404, "text_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194"}

experimental_model

Lipid-peroxyl radical challenge in liposomes

exposure

AAPH or AMVN challenge; dietary and meso zeaxanthin

limitations

Protein-associated antioxidant synergy is demonstrated in this assay, not a clinical supplement combination.

nutrient_topic

Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. · Dietary (3R,3-prime-R)-zeaxanthin

organism

Cell-free system with human GSTP1

plain_language

Binding enhanced protection of the test membrane.

primary_references

[zeaxanthin-p15949677] Synergistic effects of zeaxanthin and its binding protein in the prevention of lipid membrane oxidation. (2005). https://pubmed.ncbi.nlm.nih.gov/15949677/ DOI: 10.1016/j.bbadis.2005.02.002

tissue_or_cell_type

Egg-yolk phosphatidylcholine liposomes

Zeaxanthin: metabolism, signaling and nutrient connections (2026-09-17) · lines 262–273

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Lipid-peroxyl radical challenge in liposomes · source_derived_draft · unverified_draft

### zeaxanthin-gstp1-synergy GSTP1-bound dietary zeaxanthin synergistically inhibited peroxidation induced by either radical generator. Condition category: normal nutrient_topic: Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Binding enhanced protection of the test membrane. organism: Cell-free system with human GSTP1 tissue_or_cell_type: Egg-yolk phosphatidylcholine liposomes experimental_model: Lipid-peroxyl radical challenge in liposomes limitations: Protein-associated antioxidant synergy is demonstrated in this assay, not a clinical supplement combination. exposure: AAPH or AMVN challenge; dietary and meso zeaxanthin evidence_span: {"source_cache": "artifacts/zeaxanthin-research/15949677.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194", "start_char": 0, "end_char": 1404, "text_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194"} [zeaxanthin-p15949677] Synergistic effects of zeaxanthin and its binding protein in the prevention of lipid membrane oxidation. (2005). https://pubmed.ncbi.nlm.nih.gov/15949677/ DOI: 10.1016/j.bbadis.2005.02.002

evidence_span

{"source_cache": "artifacts/zeaxanthin-research/15949677.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194", "start_char": 0, "end_char": 1404, "text_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194"}

experimental_model

Lipid-peroxyl radical challenge in liposomes

exposure

AAPH or AMVN challenge; dietary and meso zeaxanthin

limitations

Protein-associated antioxidant synergy is demonstrated in this assay, not a clinical supplement combination.

nutrient_topic

Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. · Dietary (3R,3-prime-R)-zeaxanthin

organism

Cell-free system with human GSTP1

plain_language

The two stereoisomers were not identical in this comparison.

primary_references

[zeaxanthin-p15949677] Synergistic effects of zeaxanthin and its binding protein in the prevention of lipid membrane oxidation. (2005). https://pubmed.ncbi.nlm.nih.gov/15949677/ DOI: 10.1016/j.bbadis.2005.02.002

tissue_or_cell_type

Egg-yolk phosphatidylcholine liposomes

Zeaxanthin: metabolism, signaling and nutrient connections (2026-09-17) · lines 301–312

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Lipid-peroxyl radical challenge in liposomes · source_derived_draft · unverified_draft

### zeaxanthin-meso-bound-protection GSTP1-bound meso-zeaxanthin was more protective than bound dietary zeaxanthin in this assay. Condition category: normal nutrient_topic: Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. plain_language: The two stereoisomers were not identical in this comparison. organism: Cell-free system with human GSTP1 tissue_or_cell_type: Egg-yolk phosphatidylcholine liposomes experimental_model: Lipid-peroxyl radical challenge in liposomes limitations: Protein-associated antioxidant synergy is demonstrated in this assay, not a clinical supplement combination. exposure: AAPH or AMVN challenge; dietary and meso zeaxanthin evidence_span: {"source_cache": "artifacts/zeaxanthin-research/15949677.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194", "start_char": 0, "end_char": 1404, "text_sha256": "4ed175c0b5cf937df5a37c94739b40d713261c3a99e2bebc02b3b6a37ea3f194"} [zeaxanthin-p15949677] Synergistic effects of zeaxanthin and its binding protein in the prevention of lipid membrane oxidation. (2005). https://pubmed.ncbi.nlm.nih.gov/15949677/ DOI: 10.1016/j.bbadis.2005.02.002

evidence_span

{"source_cache": "artifacts/zeaxanthin-research/32824736.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "c5e70eca7c596aeb48b7f1cfccb9af65134926ab26737bc67e3594e4453d09f4", "start_char": 0, "end_char": 1173, "text_sha256": "c5e70eca7c596aeb48b7f1cfccb9af65134926ab26737bc67e3594e4453d09f4"}

experimental_model

Randomized double-blind placebo-controlled formulation trial

exposure

Six months; free pigments in sunflower/omega-3 oil versus mixed diacetate micromicelles

limitations

Combined delivery and ester changes prevent attribution to esterification alone; serum response is not a retinal outcome.

nutrient_topic

Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. · Dietary (3R,3-prime-R)-zeaxanthin

organism

81 healthy volunteers

plain_language

How the pigments were packaged changed their blood response.

primary_references

[zeaxanthin-p32824736] The Impact of Formulation on Lutein, Zeaxanthin, and meso-Zeaxanthin Bioavailability: A Randomised Double-Blind Placebo-Controlled Study. (2020). https://pubmed.ncbi.nlm.nih.gov/32824736/ DOI: 10.3390/antiox9080767

tissue_or_cell_type

Fasting serum carotenoids

Zeaxanthin: metabolism, signaling and nutrient connections (2026-09-17) · lines 834–845

AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Randomized double-blind placebo-controlled formulation trial · source_derived_draft · unverified_draft

### zeaxanthin-micromicelles The diacetate micromicelle formulation raised serum zeaxanthin more than the other active formulations. Condition category: normal nutrient_topic: Zeaxanthin research collection; topical membership is not evidence of a direct dietary effect. plain_language: How the pigments were packaged changed their blood response. organism: 81 healthy volunteers tissue_or_cell_type: Fasting serum carotenoids experimental_model: Randomized double-blind placebo-controlled formulation trial limitations: Combined delivery and ester changes prevent attribution to esterification alone; serum response is not a retinal outcome. exposure: Six months; free pigments in sunflower/omega-3 oil versus mixed diacetate micromicelles evidence_span: {"source_cache": "artifacts/zeaxanthin-research/32824736.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "c5e70eca7c596aeb48b7f1cfccb9af65134926ab26737bc67e3594e4453d09f4", "start_char": 0, "end_char": 1173, "text_sha256": "c5e70eca7c596aeb48b7f1cfccb9af65134926ab26737bc67e3594e4453d09f4"} [zeaxanthin-p32824736] The Impact of Formulation on Lutein, Zeaxanthin, and meso-Zeaxanthin Bioavailability: A Randomised Double-Blind Placebo-Controlled Study. (2020). https://pubmed.ncbi.nlm.nih.gov/32824736/ DOI: 10.3390/antiox9080767