Large-Scale Isolation of Three O-Methyl Anthocyanins from Bilberry (Vaccinium myrtillus L.) Extract.

Three O-methyl anthocyanidin 3-O-β-D-glucopyranosides were isolated from bilberry extract on a large-scale basis together with two non O-methyl analogues. Anthocyanidin 3-O-β-D-galactopyranosides were removed from bilberry extract together with parts of anthocyanidin 3-O-α-L-arabinopyranosides after treatment with β-galactosidase. The remaining arabinopyranosides were removed by applying acid catalytic hydrolysis. The amounts of anthocyanins recovered as flavylium trifluoroacetic acid salt were as follows: 630 mg for petunidin 3-O-β-D-glucopyranoside, 423 mg for peonidin 3-O-β-D-glucopyranoside, 588 mg for malvidin 3-O-β-D-glucopyranoside, 877 mg for delphinidin 3-O-β-D-glucopyranoside, and 742 mg for cyanidin 3-O-β-D-glucopyranoside.