{
  "abstract": "Two low-molecular-weight alginic acid fractions, G-block-rich SKP-G1 and M-block-rich SKP-G2, were sequentially isolated from a hot-water extract of sugar kelp (Saccharina latissima) alcohol-insoluble residue by acetic acid-induced and subsequent freeze-thaw-induced gelation. High-field (700 MHz) 2D 1H-1H COSY and TOCSY spectroscopy enabled comprehensive cross-peak assignments for selected alginate diad and triad sequences, supporting interpretation of 1D 1H NMR spectra. Sequence frequencies were combined with previously established inequalities [1] to calculate constrained frequency ranges for homoblocks beyond the triad level. For selected homoblock lengths up to a degree of polymerization of 18, comparison of the experimentally derived frequency ranges with frequencies predicted by chain-growth statistical models ruled out the Bernoulli model for both fractions and the first-order Markov model for SKP-G1. Applying the recently developed logarithmic cosine transformation (LCT) algorithm [2] to first- and second-derivative ATR-FTIR spectra enhanced the visualization of subtle spectral features and produced distinct fingerprints for the two fractions. As a proof of concept, LCT-transformed derivative ATR-FTIR spectra yielded distinct score distributions for the fractions in principal component analysis, suggesting their potential for chemometric differentiation of alginates with different block structures. In conclusion, extending 1H NMR-based sequence analysis to calculate constrained frequency ranges for homoblock polyads beyond the triad level, together with LCT-transformed derivative ATR-FTIR fingerprinting, expands the analytical toolkit for alginate block structure characterization.",
  "abstract_shown": true,
  "affiliations": [
    "Agriculture and AgriFood Canada"
  ],
  "article_type": "New results",
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "name": "X. Xing"
    },
    {
      "name": "B. Bajwa"
    },
    {
      "name": "K. E. Low"
    },
    {
      "name": "J. P. Tingley"
    },
    {
      "name": "V. Weiler"
    },
    {
      "name": "T. Montina"
    },
    {
      "name": "S. C. Serin"
    },
    {
      "affs": [
        0
      ],
      "name": "W. Abbott"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/b2avzbtmea3rs.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.10.21.760866",
  "fulltext_url": "https://www.biorxiv.org/content/10.64898/2026.10.21.760866v1.full",
  "id": "b2avzbtmea3rs",
  "issns": [],
  "landing_url": "https://www.biorxiv.org/content/10.64898/2026.10.21.760866v1",
  "language": null,
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "biorxiv",
      "biochemistry"
    ],
    [
      "openalex",
      "1106|Polysaccharides Composition and Applications"
    ]
  ],
  "openalex": "W7223217548",
  "pdf_url": "https://www.biorxiv.org/content/10.64898/2026.10.21.760866v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-21",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/b2avzbtmea3rs.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:09Z",
      "native_id": "10.64898/2026.10.21.760866",
      "source": "biorxiv",
      "url": "https://www.biorxiv.org/content/10.64898/2026.10.21.760866v1"
    }
  ],
  "subjects": [
    {
      "field": "biochemistry",
      "origin": "biorxiv:biochemistry",
      "subfield": "general"
    }
  ],
  "title": "Improved 1H NMR and ATR-FTIR approaches for structural characterization of high-G-block and high-M-block alginic acids isolated from sugar kelp by a two-step gelation method",
  "title_text": "Improved 1H NMR and ATR-FTIR approaches for structural characterization of high-G-block and high-M-block alginic acids isolated from sugar kelp by a two-step gelation method",
  "type": "preprint",
  "updated_at": "2026-10-30T12:29:09Z",
  "url": "https://research.draconitic.com/paper/b2avzbtmea3rs",
  "venue": "bioRxiv",
  "versions": []
}