Fruits, anthocyanins

Miyazawa, T., Nakagawa, K., Kudo, M., Muraishi, K., and Someya, K., Direct intestinal absorption of red fruit anthocyanins, cyanidin-3-glucoside and cyanidin-3,5-diglucoside, into rats and humans, J. Agric. Food Chem., 47, 1083, 1999. 

The phenolic compounds extracted from the fruit contribute to the development and stability of the wine s red color. The color evolution during vinification and aging is mainly due to chemical transformations to the phenolic compound derived from the fruit. Anthocyanins, responsible for the purple-red color of young wines, participate in reactions with other phenolic compounds to generate other, more chemically stable molecules. These changes involve oxidation, polymerization, and other... 

Robert D. Curtright, James A. Rynearson, and John Markwell, "Fruit Anthocyanins Colorful Sensors of Molecular Milieu," ]. Chem. Educ,... 

Del Carpio Jimenez, C., Flores, C. S., He, J., Tian, Q., Schwartz, S. J., Giusti, M. M. Characterisation and preliminary bioactivity determination of Berberis boliviana Lechler fruit anthocyanins. Food Chem. 128, 717-... 

Soluble HBA or HCA derivatives are frequently extracted from fmits and vegetables with ethanol or methanol-water solutions (80 0, v/v), using low temperatures and adding an antioxidant to prevent oxidation during the extraction procedure. Chemical or enzymatic hydrolysis of the plant material is necessary when phenolic acids are linked to cell wall constituents to give insoluble forms [6]. Apolar solvents or supercritical carbon dioxide may be useful to extract phenolic lipids [7,8]. In the case of acylated flavonoids, solvents must be adapted to the characteristics of the flavonoid itself, e.g., acidic methanol for fruit anthocyanins, although some artefacts may appear under these conditions. 

Sulfur dioxide (bisulfites) also reacts with thiamine yielding inactive compounds (see Section 5.6.6), forms adducts with riboflavin, nicotinamide, vitamin K, inhibits ascorbic acid oxidation (see Section 5.14.6.1.6) and reacts with ascorbic acid degradation products, reduces o-quinones produced in enzymatic browning reactions back to 1,2-diphenols (see Section 9.12.4), causes decolourisation of fruit anthocyanins (see Section 9.4.1.5.7) and reacts with synthetic azo dyes to form coloured or colourless products (see Section 11.4.1.3.2). Sulfur dioxide also reacts with pyrimidine bases in vitro, specifically with cytosine and 5-methylcytosine. Important reactions of sulfur dioxide are shown in Figure 11.4. 

He J., Silva A.M.S., Mateus N., de Freitas V. Oxidative formation and structural characterisation of new a-pyranone (lactone) compounds of non-oxonium nature originated from fruit anthocyanins. Food Chemistry, 127 984 992 (2011). 

Goldy, R.G., Ballinger, W.E., Maness, E.P., 1986. Fruit anthocyanin content of some Euvi-tis X Vitis rotundifolia hybrids. J. Am. Soc. Hortic. Sci. Ill, 955-960. 

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