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Practical ecological knowledge for the temperate reader. |
"Anthocyanins are water-soluble pigments that give plants and their fruits and flowers red, purple, or blue color, which is important for attracting animals for seed dispersal and pollination. They are a class of flavonoids derived from the flavylium cation and due to their polyphenolic structure, can act as powerful antioxidants. When coupled to a glycoside, commonly glucose or galactose, they are referred to as anthocyanins, while the aglycones are referred to as anthocyanidins. Anthocyanins are currently very popular in health research and studies have shown that they have roles in alleviating oxidative stress, inflammation, cardiovascular disease, cancer, obesity, and diabetes (He and Giusti 2010). Their role in plants beyond acting as pigments is more controversial (de Pascual-Teresa and Sanchez-Ballesta 2008)." [SVPC]
Glycosides of anthocyanidins
"The anthocyanins, anthocyanidins with sugar group(s), are mostly 3-glucosides of the anthocyanidins. The anthocyanins are subdivided into the sugar-free anthocyanidin aglycones and the anthocyanin glycosides. As of 2003, more than 400 anthocyanins had been reported,[51] while later literature in early 2006, puts the number at more than 550 different anthocyanins. The difference in chemical structure that occurs in response to changes in pH, is the reason why anthocyanins often are used as pH indicators, as they change from red in acids to blue in bases." [Wiki]
Stability
"Anthocyanins are thought to be subject to physiochemical degradation in vivo and in vitro. Structure, pH, temperature, light, oxygen, metal ions, intramolecular association, and intermolecular association with other compounds (copigments, sugars, proteins, degradation products, etc.) generally are known to affect the color and stability of anthocyanins.[52]" [Wiki]