Ellagitannins analysis

The separation characteristics of unmodified silica, diol, cyano, cellulose and RP-18 stationary phases were compared for the analysis of ellagitannins, gallotannins and flavonoid glycosides in the aerial parts of Erodium cicutarum (Geraniaceae) (stork s bill). Its decoction has been used in cases of dysentery, fever, wounds and worm infections. The air-dried and powdered plant material (300 g) was extracted three times with water-acetone (1 1, v/v) at ambient temperature. The collected extract was filtered and concentrated. The aqueous phase was acidified to pH 3 with formic acid and separated in an ODS column. Polphenols... 

W. Mullen, T. Yokota, M.E.J. Lean, A. Crozier, Analysis of ellagitannins and conjugates of ellagic acid and quercetin in raspberry fruits by LC—AdS", Phytochem., 64(2003)617. 

Analysis of toasted oak extracts shows a breakdown of the ellagitannins, especially after medium toasting (Table 13.19). This is related to the fusion temperatures of a blend of vescalagin and castala-gin (163°C) and gallic acid (250°C). Ellagic acid only reacts at higher temperatures (F > 450°C), but it is not very soluble in dilute alcohol solutions. 

Glabasnia A, Hofmann T. Sensory-directed identification of taste-active ellagitannins in American (Quercus alba L.) and European oak wood (Quercus robur L.) and quantitative analysis in bourbon whiskey and oak-matured red wines. / Agric Food Chem. 2006 54 3380-3390. 

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