Study of diversity of anthocyanin composition in bilberry (Vaccinium myrtillus L.) fruits

Qualitative and quantitative composition of anthocyanins in bilberry (Vaccinium myrtillus L.) fruits was assayed. The aim of our study was to evaluate total anthocyanin content and their composition in bilberries collected from various regions and at different time. For the quantification of total anthocyanins in frozen fruits, the spectrophotometrical assay was performed. The highest amount of anthocyanins in bilberry fruits, collected in Lithuania, was found in samples from Šilutė (0.399%), the lowest one – from Valkininkai region (0.264%), but higher amounts of anthocyanins were found in the samples collected in Russia (Archangelsk region) and Sweden (Stockholm region). High-performance liquid chromatography was applied for qualitative evaluation of individual anthocyanins in the different material. Quantification of anthocyanidin content was performed after acidic hydrolysis of anthocyanin glycosides. Chromatographic analysis has shown that there are no differences in qualitative composition of anthocyanidins. In all samples, cyanidin was found in the highest quantities (mean amount 0.053 µg/mL). Delphinidin and petunidin was found in quantities 2.5 fold lower than cyanidin, and malvidin and peonidin were found in the smallest quantities. Only in the blueberries collected in Sweden, malvidin was found in the highest amount. It was 1.5 fold higher than amounts of petunidin and delphinidin.