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Updated: Aug 29, 2026

A Generalized Method for Determining Free Soluble Phenolic Acid Composition and Antioxidant Capacity of Cereals and Legumes
Published on: June 10, 2022
Calculation of the molar absorptivity of polyphenols by using liquid chromatography with diode array detection: the
M Pelillo1, M E Cuvelier, B Biguzzi
1Dipartimento di Scienze degli Alimenti, Università degli Studi di Bologna, Via Ravennate 1020, Cesena (FC) 47023, Italy. marcocinabro@hotmail.com
Abstract:
Antioxidant activity of vegetable extracts is related to the nature and the amount of active components, mainly polyphenols; therefore, a correct quantification of these molecules should be required to define their concentration in such kind of vegetable extracts. A fast and accurate method to calculate molar absorption coefficients (epsilon), by using HPLC, has been tested on standard polyphenols and caffeine, and should be widely adapted for standardless quantitative analysis. Molar absorptivity (epsilon) of carnosic acid (CA) was determined from 200 to 300 nm, by the proposed method and those values were compared to tert-butyl-hydroxytoluene (BHT) ones for further comparative quantification.
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