Antioxidant capacity of herbal infusions and tea extracts: A comparison of ORAC-fluorescein and ORAC-pyrogallol red methodologies
| Autor: | Eduardo Lissi, Ana María Edwards, Camilo López-Alarcón, Ana Maria Campos, Emilio I. Alarcon |
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| Rok vydání: | 2008 |
| Předmět: |
Antioxidant
Chromatography Oxygen radical absorbance capacity ROUGE Aloysia biology Stereochemistry Pyrogallol red medicine.medical_treatment General Medicine biology.organism_classification Analytical Chemistry chemistry.chemical_compound Antioxidant capacity chemistry medicine Phenols Fluorescein Food Science |
| Zdroj: | FOOD CHEMISTRY Artículos CONICYT CONICYT Chile instacron:CONICYT |
| ISSN: | 0308-8146 |
| Popis: | Oxygen radical absorbance capacity (ORAC) values have been obtained for a series of teas and herbal infusions employing 2,2′-azo-bis(2-amidinopropane) as free radical source, and fluorescein and pyrogallol red as target molecules. The amounts of phenols in the extracts were evaluated by Folin’s methodology. ORAC values are extremely dependent upon the employed target molecule. Even more, relative ORAC values measured for different infusions depend upon the employed methodology. For example, ORAC-fluorescein value of Aloysia citriodora is larger than that of green tea, while if pyrogallol red is employed as target molecule green tea appears as nearly nine times more efficient. Similarly, for extracts with comparable amounts of phenols, herbal infusions are more efficient than teas by ORAC-fluorescein, while opposite conclusions are obtained if ORAC-pyrogallol red values are considered. Extreme care must then be taken for conclusions obtained from ORAC values estimated by employing a single target molecule. |
| Databáze: | OpenAIRE |
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