Abstract
The result of present investigation is in accordance with earlier studies which showed that corollas of chrysanthemum contain cyanidin 3-glucoside as the main anthocyanin. In addition to this pigment, a few anthocyanins have been isolated from many cultivars by the authors.
To characterize these unknown anthocyanins, an attempt has been made in which the properties of partial hydrolysate and of oxidation products of each anthocyanin in dark red corollas of Chrysanthemum morifolium RAMAT., cultivar“Aka-chu-san” were examined.
Four anthocyanins (A1, A2, A3, and A4) were chromatographically separated and isolated from the pigment solution of chrysanthemum corollas.
Only cyanidin was found as the aglycone of their anthocyanins. Two kinds of cyanidin glycosides were obtained by deacylation of four anthocyanins in an alkaline solution. One was cyanidin 3-glucoside (chrysanthemin) from A1 and A2 and the other cyanidin 3-diglucoside from A3 and A4. Their sugars liberated from deacylated anthocyanins were also examined by a method of oxidation with hydrogen peroxide, showing glucose and diglucose respectively.
The sugars in the glucoside form were found in 3-position of cyanidinskelton by the behavior of partial hydrolysates on chromatogram and by the ratio of E440/Emax of anthocyanin solution using spectrophotometer.
After alkaline hydrolysis, caffeic acid having the absorption maximum (λ=337nm), was identified in the hydrolysate of A2, A3 and A4.
This may be the new finding on chrysanthemum anthocyanins.
In conclusion, A1 is cyanidin 3-glucoside (chrysanthemin), A2 cyanidin 3-caffeoylglucoside, A4 cyanidin 3-caffeoyldiglucoside and A3 cyanidin 3-diglucoside having probably two molecules of caffeic acid. Of these, chrysanthemum and cyanidin 3-caffeoyl glucoside are the main anthocyanins in corollas of chrysanthemum.
