Characterization of Anthocyanins by NMR

Andersen, O.M. and Fossen, T., Characterization of anthocyanins by NMR, in Handbook of Food Analytical Chemistry Pigments, Colorants, Flavors, Texture, and Bioactive Food Components, Wrolstad, R.E., Ed., John WUey Sons, New York, 2005. 

F1.3 Separation and Characterization of Anthocyanins by HPLC FI. 4 Characterization of Anthocyanins by NMR... 

Many recent stndies of NMR spectroscopy have been reported for structure elucidation of anthocyanins from many plant materials such as carrot, tart berries, boysenberries, " flowers, black soybeans, and anthocyanin and flavonol derivatives in red wine. Ginsti et al. (1998) structurally elucidated two novel diacylated anthocyanins and two monoacylated anthocyanins from radish Raphanus sativus) by one- and two-dimensional NMR. Anderson et al. (2006) applied two-dimensional NMR to characterize carboxypyranoanthocyanins. Two 3-deoxyantho-cyanins, lnteolinidin-5-glncoside, and apigeninidin-5-glucoside were identified by Swinny et al. nsing H and C NMR. 

Remy-Tanneau, S. et al.. Characterization of a colorless anthocyanin-flavan-3-ol dimer containing both carbon-carbon and ether interflavanoid linkages by NMR and mass spectrometries. J. Agric. Food Chem. 51, 3592, 2003. 

Mechanism of reaction. The adduct of malvidin-3-glucoside with pyruvic acid, also known as vitisin A(Fig. 9A.3h), was firstly detected in fortified red wines (Bakker et al. 1997) and in a grape marc (Fulcrand et al. 1998) and further isolated and characterized by NMR (Bakker et al. 1997 Fulcrand et al. 1998). According to Fulcrand et al. (1998), the reaction between pyruvic acid and grape anthocyanins occurs through a series of steps similar to those previously described for the hydroxyphenyl-pyranoanthocyanins (Sect. 9A.2.4.1 Fig. 9A.3f). Later studies performed by NMR (Mateus et al. 2001b) and mass spectrometry (Asenstorfer et al. 2001 Hayasaka and Asenstorfer 2002) have confirmed the structure proposed by Fulcrand et al. (1998). This mechanism is extended to the condensation reaction between anthocyanins and other enolizable precursors found in wine (Benabdeljalil et al. 2000). 

The first study of the anthocyanin content of Cornus officinalis and Cornus controversa was reported by Seeram et al. in 2002. The isolation, characterization and quantification of anthocyanins in these Cornus spp. fruits was achieved by HPLC, LC-ES/MS and NMR methods. 

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