Quality control and determination of melatonin in food supplements

Melatonin supplements are used widely in Europe and the United States (US) to alleviate jet-lag and other sleep-delay disorders. Recently, the European Commission authorized two health claims for food containing melatonin, with a minimum dose per quantified portion. This study aimed to determine the...

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Detalles Bibliográficos
Autores: Cerezo López, Ana Belén, Leal, Ángela, Álvarez Fernández, María Antonia, Hornedo Ortega, Ruth, Troncoso González, Ana María, García Parrilla, María del Carmen
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2016
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/167391
Acceso en línea:https://hdl.handle.net/11441/167391
https://doi.org/10.1016/j.jfca.2015.09.013
Access Level:acceso abierto
Palabra clave:melatonin
food/dietary supplements
OrbiTrap
LC-DAD
health claim
21 dose
food analysis
food composition
Descripción
Sumario:Melatonin supplements are used widely in Europe and the United States (US) to alleviate jet-lag and other sleep-delay disorders. Recently, the European Commission authorized two health claims for food containing melatonin, with a minimum dose per quantified portion. This study aimed to determine the dose of melatonin in food supplements marketed in Europe (Spain) and the US by validating a liquid chromatography method with diode array detection (LC-DAD). Additionally, contaminants present in melatonin supplements were analyzed using ultra-high-performance liquid chromatography coupled to an orbitrap mass spectrometer. We tentatively identified 8 tryptophan-related contaminants in melatonin supplements, suggesting tighter impurity control in melatonin supplements is necessary. The LC-DAD validated method achieved reliable results regarding recovery, precision, repeatability, limit of detection, limit of quantitation and linearity. Label melatonin dose varied from 1–1.95 mg/unit and 0.3–5 mg/unit for supplements marketed in Europe (Spain) and the US, respectively. Four out of seventeen supplements showed significant deviations from melatonin content declared on the label (from −60% to −20%). Regarding health claims, three out of the ten supplements purchased in Spain should not include the claim “reduction of time taken to fall asleep”, as their melatonin content is lower than 1 mg.