{
  "abstract": "Introduction: Intrinsic stable isotope labeling enables assessment of nutrient bioavailability from intact plant food matrices by distinguishing nutrients derived from the test food from existing body pools. Although deuterium oxide (D ₂ O) has been used to intrinsically label green leafy vegetables under hydroponic growth conditions, well-characterized protocols for static hydroponic systems remain limited.\n\nMethods: This study established and evaluated a novel hydroponic D ₂ O-labeling protocol using spinach to produce intrinsically labeled α-tocopherol (α-T) and phylloquinone (VK1). Three independent experiments were conducted in a controlled-environment growth chamber. Spinach seedlings were transferred to a static hydroponic system containing 0% (control) or nominal 30% (v/v) D ₂ O nutrient solution. Plants grown under controlled environmental conditions were harvested at Weeks 4, 5, and 6 to evaluate leaf biomass, nutrient content, and isotopomer distributions.\n\nResults: No labeling condition × harvest time interactions occurred for leaf biomass, α-T content, or VK1 content ( p > 0.05). Leaf biomass, α-T content, and VK1 content increased from Week 4 to Week 6 ( p < 0.05) but were unaffected by labeling condition ( p > 0.05). Compared with non-D ₂ O-grown spinach, D ₂ O-grown spinach demonstrated significantly higher relative abundance of the summed d ₃ –d ₂₀ mass isotopomers for α-T (98.7–99.0% vs 3.6–4.6%; p = 0.0002) and VK1 (97.0–97.5% vs 1.8–2.1%; p = 0.0008). The dominant labeled isotopomers were d ₉ for α-T and d ₈ –d ₉ for VK1. Inter-experiment coefficients of variation for the summed d ₃ –d ₂₀ relative abundance ranged from 0.1–0.3% for α-T and 0.1–0.4% for VK1 across harvest times.\n\nDiscussion: These findings provide a detailed framework for a static hydroponic D ₂ O-labeling method that produced similar α-T and VK1 isotopomer distributions across three experiments conducted in the same laboratory, with potential application in future bioavailability and metabolic tracing research.",
  "abstract_shown": true,
  "affiliations": [
    "Human Nutrition Program, Department of Human Sciences, The Ohio State University",
    "Department of Horticulture and Crop Science, The Ohio State University",
    "Laboratory for the Analysis of Metabolites from Plants (LAMP), The Ohio State University"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Shahabeddin Rezaei"
    },
    {
      "affs": [
        0
      ],
      "name": "Sisi Cao"
    },
    {
      "affs": [
        0
      ],
      "name": "Min Zeng"
    },
    {
      "affs": [
        0
      ],
      "name": "Maria L. Antonius"
    },
    {
      "affs": [
        0
      ],
      "name": "Allyson Q. McHenry"
    },
    {
      "affs": [
        0
      ],
      "name": "Richard S. Bruno"
    },
    {
      "affs": [
        1,
        2
      ],
      "name": "Joshua J. Blakeslee"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/b81fzgkw0ng0p.bib",
  "cited_by": 0,
  "doi": "10.3389/fpls.2026.1915355",
  "fulltext_url": "https://europepmc.org/articles/PMC13713610",
  "id": "b81fzgkw0ng0p",
  "issns": [
    "1664-462X"
  ],
  "landing_url": "https://www.frontiersin.org/articles/10.3389/fpls.2026.1915355/full",
  "language": "eng",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Original Research"
    ],
    [
      "openalex",
      "3003|Chemical Reactions and Isotopes"
    ]
  ],
  "openalex": "W7221777199",
  "pdf_url": "https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2026.1915355/pdf",
  "pmcid": "PMC13713610",
  "pmid": "42952667",
  "published": "2026-10-14",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/b81fzgkw0ng0p.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:25Z",
      "native_id": "10.3389/fpls.2026.1915355",
      "source": "crossref",
      "url": "https://www.frontiersin.org/articles/10.3389/fpls.2026.1915355/full"
    },
    {
      "first_seen": "2026-10-31T00:20:41Z",
      "native_id": "MED:42952667",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42952667"
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    {
      "first_seen": "2026-10-31T12:24:07Z",
      "native_id": "PMC13713610",
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  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:3003|Chemical Reactions and Isotopes",
      "subfield": "pharmacology-toxicology"
    }
  ],
  "title": "Intrinsic deuterium labeling of spinach: a hydroponic method to enrich isotopic labeling of vitamins E and K suitable for human bioavailability studies",
  "title_text": "Intrinsic deuterium labeling of spinach: a hydroponic method to enrich isotopic labeling of vitamins E and K suitable for human bioavailability studies",
  "type": "peer-reviewed",
  "updated_at": "2026-11-01T12:21:15Z",
  "url": "https://research.draconitic.com/paper/b81fzgkw0ng0p",
  "venue": "Frontiers in Plant Science",
  "versions": []
}