Phenols/polyphenols fractionation procedure

Extensive reviews of analytical methods for anthocyanins (Francis, 1982 Jackman et al., 1987b Strack and Wray, 1994) and other flavonoids (Williams and Harbome, 1994) as well as phenolic acids (Herrmann, 1989) have been published. In these reviews, extraction procedures, methods for fractionation of groups of polyphenols and the identification and quantification of individual components are presented. Here, a brief presentation of more recently published methods for grape and berry polyphenolic analyses is given with respect to their relationship to antioxidant activity and health benefits. 

Recently, Romani et al. [200] published a sophisticated solid phase extraction procedure for the qualitative analysis of grape skins. In a first extraction on Extrelut 20 (kieselguhr, Merck) polyphenols are separated from anthocyanins. The polyphenols are subsequently fractionated on a C-18 cartridge (Bond Elut , Varian) into phenolic acids and esters, procyanidins, flavonol glycosides and acylated anthocyanins. 

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