Flavonoids malvidin

In the intermolecular reactions between anthocyaifins and flavonoids mediated by acetaldehyde, new compounds linked by an ethyl bridge are formed. Three new compounds were detected by the reaction of malvidin 3-glucoside and proanthocy-... 

In products with complex combinations of various types of flavonoids and other phenolic compounds, effort has been made to ascribe the antioxidant activity of the product to different classes of polyphenols. Frankel et al. (1995) studied 20 selected California wines and related the antioxidant activity to the polyphenolic components of the wines, rather than to resveratrol. Antioxidant activity was measured by the ability of the wines to inhibit copper-catalyzed oxidation of human LDL. The correlation coefficient between antioxidant activity and total phenolic components of the wines was r = 0.94. Individual phenolic compounds (gallic acid, catechin, myricetin, quercetin, caffeic acid, rutin, epicatechin, cyanidin, malvidin-3-glucoside) contributed to the antioxidant activity. The correlation coefficient for the compounds ranged from r = 0.92 to r = 0.38 in descending order. 

Proteins have strong binding properties with flavonoid antioxidants in foods and biological systems, and generally increase the oxidative stability of liposomes. The addition of bovine serum albumin (BSA) increased the oxidative stability of a lecithin-liposome and changed the relative antioxidant activity of various pairs of flavonoids and phenolic acids (Table 10.13). In the absence of BSA, the activity of phenolic antioxidants decreased in the order ferulic acid > epicatechin > catechin > malvidin > caffeic acid quercetin > propyl gallate. In the presence of BSA, the activity of malvidin increased, followed by rutin and ferulic acid, but the activity of epicatechin and catechin decreased. 

The most important members of the flavonoid family include anthocyanidins (e.g., cyanidin, delphinidin, malvidin), flavonols (e.g., quercetin, kaempferol), flavones (e.g., luteolin, apigenin), flavanones (e.g., myricetin, naringin, hesperetin, naringenin), flavan-3-ols (e.g., catechin, epicatechin, gallocatechin) and, although sometimes classified separately, the isoflavones (e.g., genistein, daidzein). For chemical structures see Figure 1. All these phytochemical are frequently referred to as bioflavonoids due to well established effects in human health maintenance. 

Anthocyanins in C. roseus are highly dependent on the cultivar under study, which can result in different petal color. As so. Little Bright Lye, a white variety, seems to be disposed of these compounds [16], while other varieties have been shown to contain this class of flavonoids. In particular, the 3-0-glucosides of malvidin, hirsutidin, and petunidin have been described, as well as their... 

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