Cyanidin 3-glucoside, isolation

Research into the copigmentation of anthocyanins started as early as 1913 when Willstatter and Everest determined the chemical structure of cyanidin 3-glucoside isolated from blue cornflowers and red roses, and attributed the color changes to different pH levels in cell saps. This theory, however, was questioned and in 1916, Willstatter and Zollinger,revising the previous work, proposed a new theory according to which the colors of the anthocyanins varied significantly by the effects... 

Four cyanidins with 4 -glucosidation were recently isolated in minor amounts from pigmented scales of red onion. Two were the only anthocyanins with B ring sugar substitutions and no glycosyl moieties in anthocyanidin position 3, whereas the other two were also glycosilated at the usual position 3. ... 

Arteel and Sies (1999) examined procyanidin oligomers of different size, isolated from the seeds of Theobroma cacao, for their ability to protect against nitration of tyrosine. Serraino and others (2003) investigated antioxidant activity of the blackberry juice and cyanidin-3-O-glucoside on endothelial dysfunction in cells and in vascular rings exposed to peroxynitrite. However, more work is needed in this area, and the confounding effects of oxidized protein/amino acids in the diet need to be elucidated. 

Four cyanidin 4 -glucosides have recently been isolated from pigmented scales of red onion. These structures were established by extensive use of 2D NMR spectroscopy and electrospray LC MS. The previous report on 4 -glucosyl linkages in two anthocyanins from... 

Oxalic acid is another dicarboxylic acid with restricted occurrence as an acyl moiety of anthocyanins. In addition to some European orchids flowers (Section 10.5.10), cyanidin 3-dioxalylglucoside has been isolated from fruits of Rubus laciniatus. Altogether six different anthocyanins acylated with oxalic acid have been reported. With the exception of cyanidin 3-[6-(oxalyl)glucoside], evidences for proper determination of the linkage position of this acyl moiety are absent. 

Kamsteeg, J., Van Brederode, J., Hommels, C.H. and Van Nigtevecht, G. (1980) Identification, properties and genetic control of hydroxycinnamoy 1-coenzyme A antho-cyanidin 3-rhamnosyl (1 6) glucoside, 4 -hydroxycinnamoyl transferase isolated from petals of Silene dioica. Biochem. Physiol. Pfanzen, 175, 403-11. 

Glucosides of cyanidin occur m ma ay flowers and fruits, e.g. cornflower, peony, chrysanthemum, cherry and cranberry Usuwy isolated in form of its chloride. Chocolate-brown needles or prisms from EtOH- HCl. 

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