Delphinidin 3-O- - 3-glucoside

Fig. 2.101. Chromatograms of Cabernet Sauvignon and TempraniUo wines recorded at 520 nm. Peak identification Df-3-GL = delphinidin-3-O-glucoside Cy-3-Gl = cyanidin-3-O-glucoside Pt-3-Gl = petunidin-3-O-glucoside Pn-3-Gl = peonidin-3-O-glucoside Mv-3-Gl = maMdin-3-O-glucoside Pn-3-Gl-Ac = paeonidin-3-O-acetylglucoside Mv-3-Gl-Ac = maMdin-3-O-acetylglucoside Pn-3-Gl-Cm = peonidin-3-coumaroylglucoside Mv-3-Gl-Cm = malvidin-3-coumarylglucoside. Reprinted with permission from E. Revilla et al. [235].

Fig. 4.2 HPLC-DAD chromatograms of anthocyanins from soluble and insoluble extracts of black, red-brown, and brown soybean seed coats at 520 nm. (a, d) Black (Clark), (b, e) red-brown (Mil), and (c, f) brown (MlOO) seed coats, (a and b) Pulverized fresh seed coats extracted with 80% methanol in water, (d-f) Insoluble pulverized seed coat fraction extracted with 1-butanol/HCl (19 1) 1% SDS. Compound identifications were based on comparison of retention times and absorption spectra to authentic standards. Peak 1, unknown peak 2, delphinidin-3-O-galactoside peak 3, delphinidin-3-O-glucoside peak 4, cyanidin-3-O-galactoside peak 5, cyanidin-3-O-glucoside peak 6, petunidin-3-O-glucoside peak 7, pelargonidin-3-O-glucoside peak 8, peonidin-3-O-glucoside and peak 9, malvidin-3-O-glucoside...

Gentianin (p-coumaiic acid ester of delphinidin 3-O-glucoside). C30H27O14, Mr 611.54, blue-violet powder. G. occurs in the flowers of blue gentian (Gentiana verna). The major representative of the Gentiana alkaloids, a monoterpenoid iridoid, also has the name gentianine. 

Anthocyanin 3-0-glucosldes (17) Palargonidin 3-0 glucoside Cyanidln 3-(>9luco ide Delphinidin 3-O-glucoside... 

The fruits of Cornus alternifolia showed similar anthocyanin profile as those of Cornus controversa [Vareed et al., 2006], the relative amounts of anthocyanins in these fruits were found in the following order delphinidin-3-O-rutinoside > delphinidin-3-O-glucoside cyanidin-3-O-glucoside. The anthocyanin content in Cornus alternifolia fruits was several times higher than in other commonly consumed fiuits. 

The effects of pH under model conditions (0.6 to 5.5 for 24 hr) were covered by Nielsen et al. for four anthocyanins (3-O-glucoside, glycosylated cyanidin, rutinoside, and delphinidin rutinoside). After 24 hr, over 90% of the anthocyanins were intact up to pH 3.3, while instabihty greatly increased at pH greater than 4.5. 

The riocus encodes the enzyme flavonoid 3 -hydroxylase (F3 H) [17, 18], and is an important controller of flux in the anthocyanin pathway in soybean seed coats (Fig. 4.1). F3 H diverts metabolic flux away from biosynthesis of orange (pelargoni-din) and blue (delphinidin) anthocyanins toward the red cyanidin-3-(9-glucoside, which is the main anthocyanin in the seed coats of black soybean [7, 8]. T increases the accumulation of delphidin-3-O-glucoside in black seed coats, even though it is not required for its biosynthesis [19]. Possible mechanisms for this include positive feedback, or the stabilization of the putative anthocyanin biosynthetic metabolon [20] by F3 Fl-derived membrane anchoring (Fig. 4.1). 

Quercetin, isorhamnetin, quercitrin, kaempferol 3-O-rutinoside, isorhamnetin 3-O-glucoside, and morin Betulinic acid, oleanolic add, and ursolic add Vanillic acid, caffeic add, p-coumaric add, ferulic acid, delphinidin, cyanidin, quercetin, kaempferol, isorhamnetin, procyanidin B2, and procyanidin B3... 

There are at least 10 more anthocyanidins in nature, practically always appearing as glycosides. The number of anthocyanins far exceeds that of anthocyanidins, since monosaccharides, disaccharides, and at times trisaccharides glycosylate the anthocyanidins at various positions (always at 3, occasionally at 5, and seldom at other positions). Eventual acylation with p-coumaric, caffeic, and ferulic acids increases the number of natural anthocyanins. An example of acylated anthocyanin is the dark purple eggplant pigment delphinidin, 3-[4-(p-coumaroyl)-L-rhamnosyl-(l 6)-D-glycosido] 5-o-glucoside. 

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