Malvidin-3-glucoside and catechin

Pissara, J. et al., Reaction between malvidin 3-glucoside and (+)-catechin in model solutions containing different aldehydes. J. Food Sci. 68, 476, 2003. 

Colored adducts in which the anthocyanin and the flavanol are linked by a carboxy-methine bridge, have also been identified, in addition to colorless carboxy-methine-linked catechin dimers (Chapter 9B), in model solutions containing (-i-)-catechin, malvidin-3-glucoside and glyoxylic acid (Es-Safi et al. 2003). 

Sousa, C., Mateus, N., SUva, A.M.S., Gonzalez-Paramas, A.M., Santos-Buelga, C., De Freitas, V. (2007). Stmctural and chromatic characterization of a new malvidin-3-glucoside-vanillyl-catechin pigment. Food Chem. 102, 1344—1351. 

The presence of the dimers malvidin-3-glucoside-ethyl-catechin (m/z 809, [M]" and malvidin-3-(6-p-coumaroyl)-glucoside-ethyl-catechin (m/z 955, [M] ) has been confirmed in wine and wine fractions with the help of ESI-MS. Other pigments (see below), in which the anthocyanin is joined to a flavanol via a vinyl fragment, can also be produced in the presence of acetaldehyde. 

The effects of catechin, epicatechin, procyanidin B2, caffeic acid, / -coumaric acid, myricetrin, and quercetrin on the color intensity and stability of malvidin 3-glucoside at a molar ratio of 1 1 under conditions similar to red wine were evaluated. " Flavan 3-ols appeared to have the lowest protective effects and flavonols the highest strong color changes were visually perceptible. " In the complexation of malvin chloride and natural polyphenols, flavonol glycosides by far exerted the best protector effect. ... 

Duenas, M., et al., UV-visible spectroscopic investigation of the 8,8-methylmethine catechin-malvidin-3-glucoside pigments in aqueous solutions structural transformations and molecular complexations with chlorogenic acid, J. Agric. Food. Chem., 54, 189, 2006. 

Direct condensation product between catechin and malvidin-3-glucoside... 

Several aldehydes, namely furfural, 5-hydroxymethylfurfural, " isovaleraldehyde, benzal-dehyde, propionaldehyde, isobutyraldehyde, formaldehyde, and 2-methylbutyraledehyde, were shown to react with catechin and malvidin 3-glucoside in the same way as acetaldehyde or... 

Escribano-Bailon, T. et al., Color and stability of pigments derived from the acetaldehyde-mediated condensation between malvidin-3-O-glucoside and (+)-catechin. J. Agric. Food Chem. 49, 1213, 2001. 

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