Purification and identification of Capulin (Prunus serotina Ehrh) anthocyanins

Capulin (Prunus serotina Ehrh) anthocyanins were extracted from liquid nitrogen powdered epidermal tissue using acetone, the aqueous acetone extract partitioned with chloroform and purified in a C-18 solid-phase cartridge. pH-differential and bisulfite bleaching methods were used to determine monomeric anthocyanin content and polymeric color. Pigments were identified by spectral analyses, HPLC and mass spectroscopy. Information from HPLC profiles, saponification and acid hydrolysis of the capulin anthocyanins showed that the two major pigments were cyanidin-3-glucoside (34%) and cyanidin-3-rutinoside (63%), with no acylating groups. A third yellow/orange pigment (λmax 480 nm, MW=632) possibly containing rutinose was detected by MS.