Using stable carbon isotope ratio analysis to detect adulteration in red yeast rice dietary supplements.

Autor: Hannon KM; US FDA/ORA/ORS/OMPSLO, Forensic Chemistry Center, 6751 Steger Drive, Cincinnati, OH, 45237, USA., Sabala JD; US FDA/ORA/ORS/OMPSLO, Forensic Chemistry Center, 6751 Steger Drive, Cincinnati, OH, 45237, USA., Mantha M; US FDA/ORA/ORS/OMPSLO, Forensic Chemistry Center, 6751 Steger Drive, Cincinnati, OH, 45237, USA., Lorenz LM; US FDA/ORA/ORS/OMPSLO, Forensic Chemistry Center, 6751 Steger Drive, Cincinnati, OH, 45237, USA., Roetting Ii JP; US FDA/ORA/ORS/OMPSLO, Forensic Chemistry Center, 6751 Steger Drive, Cincinnati, OH, 45237, USA., Perini M; Fondazione Edmund Mach, Via E. Mach 1, 38098, San Michele All'Adige, TN, Italy., Pianezze S; Fondazione Edmund Mach, Via E. Mach 1, 38098, San Michele All'Adige, TN, Italy., Kubachka KM; US FDA/ORA/ORS/OMPSLO, Forensic Chemistry Center, 6751 Steger Drive, Cincinnati, OH, 45237, USA. Electronic address: kevin.kubachka@fda.hhs.gov.
Jazyk: angličtina
Zdroj: Talanta [Talanta] 2024 Jan 01; Vol. 266 (Pt 2), pp. 125076. Date of Electronic Publication: 2023 Aug 23.
DOI: 10.1016/j.talanta.2023.125076
Abstrakt: Red yeast rice (RYR) is marketed as a dietary supplement because it contains natural 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins), including monacolin K. However, there is concern that some RYR supplements may be adulterated with the pharmaceutical drug lovastatin to enhance health claims. We have developed an optimized method to isolate monacolin K/lovastatin from complex RYR dietary supplement matrices to then test for adulteration in RYR supplements using stable carbon isotope (δ 13 C) analysis. Samples were initially screened for monacolin K/lovastatin using liquid chromatography with mass spectrometric detection (LC-MS). To ensure the extraction process did not affect the measured isotopic values (i.e., isotopic fractionation effects), neat lovastatin standards were spiked into two types of blank RYR matrices (powder and gel). The monacolin K/lovastatin peaks were detected using high performance liquid chromatography with ultraviolet detection (HPLC-UV) and isolated using fraction collection. Residual matrix components were removed from targeted fractions by solid phase extraction (SPE) using graphitized carbon black cartridges. The resulting isolates were then analyzed using elemental analyzer-isotope ratio mass spectrometry (EA-IRMS) to measure δ 13 C values. The δ 13 C values of the extracted lovastatin standards were compared to their respective neat lovastatin δ 13 C values and demonstrated negligible isotopic fractionation effects. Using this optimized clean up method and carbon isotope analysis, thirty-one samples were screened. Eight RYR dietary supplement samples had >0.8 mg/g of monacolin K/lovastatin, our minimum threshold for analyzing samples using this method. Four of these eight samples had δ 13 C values greater than -28.3‰, a previously proposed cutoff value for natural monacolin K, indicating likely adulteration. Additionally, five RYR powder samples were analyzed as part of a collaborative study using in-house methods from two laboratories and the data shows acceptable agreement in the δ 13 C values of monacolin K/lovastatin (differences ranging from ±0.02‰ to ±0.76‰). This optimized method represents a robust, reproducible procedure for detecting lovastatin adulteration in dietary supplements with minimal isotopic fractionation.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Published by Elsevier B.V.)
Databáze: MEDLINE
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