Abstract: To fully develop the potential application of blueberry fruits, this paper is focused on the preparation of anthocyanin monomers from blueberry fruits using column chromatography and semi-preparative high performance liquid chromatography (HPLC). Crude blueberry anthocyanins were ultrasonically extracted with acidified 70% ethanol and further subjected to two cycles of ethyl acetate extraction for the purpose of facilitating the dissolution of anthocyanins and removing non-anthocyanin flavonoids. The purity of crude blueberry anthocyanins reached 62.49% after Amberlite XAD-7HP column chromatography separationand Sep-Pak C18 solid-phase extraction. Three anthocyanin fractions were obtained by Sephadex LH-20 column chromatography with purities ranging from 65% to 75%. Using semi-preparative HPLC, two pure anthocyanin monomers were successfully isolated from the three purified anthocyanin fractions, which were identified as delphinidin-3-O-galactoside and malvidin-3-O-galactoside by analytical HPLC, with purities of 96.98% and 95.63% respectively. The present study can provide technical references for large-scale production of anthocyanin glycoside monomers, and also provide a good theoretical basis for the production of high value-added products of blueberry anthocyanins.

Key words: blueberry, anthocyanins, column chromatography, semi-preparative high performance liquid chromatography (HPLC), separation and purification