Crocine glycosides

N.A. Crocine glycosides, beta-carotene, phytoene, phytofluene, pinene, safranal, cineole.100-107 Saffron stomachic, antispasmodic, emmenagogue properties. 

Crocin is a yellow-orange glycoside that is freely soluble in hot water, slightly soluble in absolute alcohol, glycerol, and propylene glycol, and insoluble in vegetable oils. Crocin melts with decomposition at about 186°C and has absorption maxima in methanol at about 464 nm and 434 nm. 

Main components 0.4-1% essential oil, which contains app. 50% of the odour carrier safranal. For further components of the oil see [258, 259[. Safranal is formed by hydrolysis from the glycoside picrocrocin, which causes the bitter taste. Carotinoids, mainly the water-soluble crocin (crocetin digentiobiose ester) and other crocetin derivatives [260[, a- and P-carotin, zeaxanthin and lycopin are responsible for the colouring effect. 

Saffron is a mixture of substances. Those that make it desirable as a spice and dye are among the ones the plant uses to attract insects. Two of them, crocetin and crocin, are mainly responsible for its color, another (safrana ) its odor, and another picrocrocin) its taste. The same 20-carbon conjugated polyene unit is the chromophore that gives crocetin and crocin their yellow color. The difference between the two is that crocin is a glycoside in which both carboxylic acid functions of crocetin are attached to a disaccharide igentiobiose) by ester linkages. 

Definition Dried stigmata of Crocus sativus, contg. glycoside picrocrocin, coloring principles crocin and crocetin... 

Although crocin is an acyl derivative and not a true glycoside, it appears to be derived from a glycoside pro-crocin (see below). 

This carboxylic acid carotenoid is the yellow tiobiose. The diester, called crocin, is therefore pigment of saffron. It occurs in plants as a di- water-soluble, ester, i. e. glycoside with the disaccharide gen-... 

Crocetin (329) occurs in the stigma of saffron flowers Crocus sativd) together with crocin, the bis(glycoside) with gentiobiose of crocetin. It is used as a yellow color in foods, in the form of intact stigma rather than as an extracted dye. 

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