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Record W256469277

Analysis of the hypericin and pseudohypericin content of commercially available St John's Wort preparations.

2003· article· en· W256469277 on OpenAlex
Andrew H. Draves, Scott Walker

Why this work is in the frame

A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.

affAt least one author lists a Canadian institution in the pinned OpenAlex snapshot.
aboutThe title or abstract carries a Canadian signal from the geographic lexicon.

Bibliographic record

VenuePubMed · 2003
Typearticle
Languageen
FieldAgricultural and Biological Sciences
TopicNatural Compound Pharmacology Studies
Canadian institutionsSunnybrook Health Science Centre
Fundersnot available
KeywordsHypericinMedicineHypericum perforatumTraditional medicineChromatographyPharmacologyChemistry
DOInot available

Abstract

fetched live from OpenAlex

CONTEXT: The use of herbal medications and supplements has been growing worldwide with over four billion dollars a year spent on alternative medicines in the United States. St John's wort herbal preparations are generally standardized to "total hypericins" as a means of illustrating a degree of quality control to the consumer. This standardization has been based on a nonspecific method that overestimates and sums the two major naphthodianthrone compounds (hypericin and pseudohypericin) that are found in these products. OBJECTIVE: To use a more specific and sensitive method to accurately determine the total hypericin content (sum of hypericin and pseudohypericin) in commercially available St John's wort herbal preparations. DESIGN: The current standard method for determining the naphthodianthrone content is a spectrophotometric method specified in the United States Pharmacopeia. Compounds other than hypericin and pseudohypericin can contribute falsely to the naphthodianthrone concentration, reducing this methods specificity. SETTING: Fifty-four commercially available St John's wort products were purchased in Canada and the United States. MAIN OUTCOME MEASURES: A specific and sensitive liquid chromatographic method with fluorescent detection was used to specifically quantify the hypericin and pseudohypericin content in commercially purchased St John's wort products. RESULTS: Analysis revealed large variations in total naphthodianthrone content, with the percentage of label claim varying from 0% to 108.62% for capsules, and from 31.34% to 80.18% for tablets. The content of tinctures varied from zero to 118.58 microg/ml. Only two products were observed to have a total naphthodianthrone concentrations within 10% of their label claim. CONCLUSIONS: When the active or marker compounds in an herbal or alternative medicine have been identified, standardization is an important step to ensure consistency from batch to batch. However, consistency is not apparent between brands and most products have inaccurate label claims. On average, most labels overestimate the hypericin and pseudohypericin content by a factor of almost two.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

Full frame distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.053
Threshold uncertainty score0.105

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.001
Science and technology studies0.0000.000
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0000.000

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.069
GPT teacher head0.231
Teacher spread0.162 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it