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1.
J AOAC Int ; 92(3): 797-805, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19610370

RESUMEN

Botanical extracts are standardized to > or = 1 marker compounds (MCs). This standardization provides a certain level of quality control, but not complete quality assurance. Thus, industries are looking for other satisfactory systems to improve standardization. This study focuses on the standardization of herbal medicines by combining 2 parameters: the concentration of the MC and antioxidant capacity. Antioxidant capacity was determined with the oxygen radical absorbance capacity (ORAC) method and the concentrations of the MCs, by high-performance liquid chromatography. Total phenols were also determined by the Folin-Ciocolteau method. The ORAC values, expressed as micromol Trolox equivalents/100 g (ORAC %), of 12 commercial herbal extracts were related to the ORAC values of the respective pure MCs at the concentrations at which the MCs occur in products (ORAC-MC %). The ORAC % values of 11 extracts were higher than those of the respective MCs and the ratios ORAC-MC %/ORAC % ranged from 0.007 to 0.7, whereas in the case of Olea europaea leaves, the same ratio was 1.36. The ORAC parameters and their ratios, as well as the linear relationship between ORAC-MC % and ORAC %, are described and discussed as tools for improving the standardization of herbal products and detecting modifications due to herb processing and storage.


Asunto(s)
Antioxidantes/análisis , Cromatografía Líquida de Alta Presión/métodos , Extractos Vegetales/normas , Liofilización , Fenoles/análisis , Extractos Vegetales/análisis
2.
J Agric Food Chem ; 53(26): 9860-6, 2005 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-16366666

RESUMEN

Immature bitter orange fruit and its extracts have been introduced into the market as an alternative to Ephedra in weight loss products. However, the safety of the immature bitter orange fruit and its extracts is a debated argument due to the presence of synephrine, a constituent known as a sympathomimetic agent. In this paper, we describe the development of a new, rapid, and simple liquid chromatography-electrospray ionization-tandem mass spectrometry method devoted to the quantitative determination of synephrine in bitter orange samples, containing a high quantity of synephrine, and sweet orange samples, known to contain a low level of synephrine but at the same time being one of the main synephrine sources in a normal human diet. Two bitter orange dry extracts containing 5 and 6% sSynephrine and 10 sweet orange samples have been analyzed. Between the sweet orange samples, six were fresh oranges and four were fresh-squeezed juices; in these samples, the synephrine levels ranged from 0.00128 to 0.00349%.


Asunto(s)
Citrus/química , Sinefrina/análisis , Bebidas/análisis , Calibración , Cromatografía Liquida , Extractos Vegetales/análisis , Estándares de Referencia , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Ultravioleta
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