Isolation of two anthocyanin sambubiosides from bilberry (Vaccinium myrtillus) by high-speed counter-current chromatography.

High-speed counter-current chromatography (HSCCC) was used for the separation of anthocyanins on a preparative scale from bilberry fruit crude extract (Vaccinium myrtillus, Ericaceae) with a biphasic solvent system composed of methyl tert-butyl ether-n-butanol-acetonitrile-water-trifluoroacetic acid (1:4:1:5:0.01, v/v). Each injection of 500 mg crude extract yielded 130 mg of pure delphinidin-3-O-sambubioside, and 77 mg of pure cyanidin-3-O-sambubioside. The two anthocyanin disaccharides with a glucose (2 --> 1) xylose unit are novel compounds for bilberry fruit, and were elucidated by means of electrospray ionization MS-MS, 1H, 13C, distortion less enhancement by polarization transfer NMR, and two-dimensional HC-correlation experiments (heteronuclear multiple bond correlation and heteronuclear multiple quantum correlation).