Delphinidin Anthocyanins

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). 

Anticancer activity was demonstrated in laboratory tests using extracts of leaves from a related species, Myrica gale, and a delphinidin (anthocyanin) extract showed anticancer and antiviral activity in test-tube experiments. 

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. 

Whereas the anthocyanins bear hues from orange (pelargonidin) to red (cyanidin) to blue (delphinidin), the betalains may be subdivided into distinct yellow-orange (betaxanthins) and red-violet stractures (betacyanins). On the other hand, betalainic... 

Wu, X., Cao, G., and Prior, R.L., Absorption and metabolism of anthocyanins in elderly women after consumption of elderberry or blueberry, J. Nutr, 132,1865, 2002. Matsumoto, H. et al.. Orally administered delphinidin 3-rutinoside and cyanidin 3-rutinoside are directly absorbed in rats and humans and appear in the blood as the intact forms, J. Agric. Food Chem., 49, 1546, 2001. 

The color stability of strawberry syrup with or without fortification with anthocyanins from black currants (cyanidin and delphinidin 3-glucosides and 3-rutino-sides) and/or AA with levels equivalent to those existing in black currant syrup was investigated. Black currant-fortified strawberry anthocyanins showed higher stability the addition of AA diminished stability. ... 

Takeoka, G.R. et al., Delphinidin 3-0-(2-0-P-D-glucopyranosyl-a-L-arabinopyrano-side) a novel anthocyanin identified in Beluga black lentils, J. Agric. Food Chem., 53, 4932, 2005. 

The W1 locus encodes flavonoid 3 5 -hydroxylase F3 5 H) [21]. F3 5 H diverts metabolic flux into the blue delphinidin branch of anthocyanin biosynthesis (Fig. 4.1). In the absence of F3 H activity (f), Wi and recessive wl give imperfect black and buff seed colors, respectively [10]. However, in black seeds, F3 H (T) phenotypically masks Wl. In contrast to its role in seeds, Wl has a prominent role in flower colors, as delphinidin-based anthocyanins are the major pigments in purple soybean flowers [22, 23]. Interestingly, F3 5 H is expressed at very low levels in flowers and seeds [21]. This suggests that, out of the two branch-point genes (i.e., F3 H and F3 5 H), it is the strong expression of F3 H in seed coats and weak expression in the flowers that determines preferential accumulation of cyanidin-based and delphinidin-based anthocyanins in these respective tissues [21]. 

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...

Cao, G., Muccitelli, H.U., Sanchez-Moreno, C., and Prior, R.L., Anthocyanins are absorbed in glycated forms in elderly women a pharmacokinetic study. Am. J. Clin. Nutr., 73, 920, 2001. Matsumoto, H., Inaba, H., Kishi, M., Tominaga, S., Hirayama, M., and Tsuda, T., Orally administered delphinidin 3-rutinoside and cyanidin 3-rutinoside are directly absorbed in rats and humans and appear in the blood as the intact forms, J. Agric. Food Chem., 49, 1546, 2001. Netzel, M., Strass, G., Janssen, M., Bitsch, I., and Bitsch, R., Bioactive anthocyanins detected in human urine after ingestion of blackcurrant juice, J. Environ. Pathol. Toxicol. Oncol, 20, 89, 2001. 

Parasitic plants often use chemicals released by their host plant to stimulate seed germination, to locate the host, or for haustorial development. Many different compounds are involved, including strigolactones, quinones, coumarins, flavonoids, and other phenolics. Flavonoids contribute to signaling in some species but not others. Haustorial development in Triphysaria versicolor can be induced in vitro by the anthocyanidins petunidin, cyanidin, pelargonidin, delphinidin, as well as their glycosides obtained from the host plant.Anthocyanins are not usually found in root exudates, however, and thus the mechanism by which they affect natural signals for parasitic plants in the soil is not clear. 

In addition to the 18 anthocyanidins listed previously, Table 10.1 contains seven new desoxyanthocyanidins and a novel type of anthocyanidin called pyranoanthocyanidins. While 31 monomeric anthocyanidins have been properly identified, most of the anthocyanins are based on cyanidin (30%i), delphinidin (22%i), and pelargonidin (18%), respectively (Figure 10.2). Altogether 20%i of the anthocyanins are based on the three common anthocyanidins (peonidin, malvidin, and petunidin) that are methylated. Around 3, 3, and 2% of the anthocyanins or anthocyanidins are labeled as 3-desoxyanthocyanidins, rare methylated anthocyanidins, and 6-hydroxyanthocyanidins, respectively. 

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