Study on solid phase extraction in the purification of apple polyphenols

A method of solid phase extraction combined with HPLC determination of polyphenols in apple was studied. Taking apple lyophilized powder as raw material, recovery of the polyphenols as the measure indicators, Waters Oasis HLB was screened out from four kinds of solid phase minicolumns to purify the apple extract. Gradient eluation was carried out on the chromatographic column phenomenex Luna C18 (150mm ×4.6mm, 5μm) with the mobile phase consisted of 0.1% formic acid solution (v/v) and acetonitrile. Under these conditions, the components of apple polyphenols can be perfectly separated. An UV-detector was used for recording the chromatographic peaks of the apple polyphenols at 280 nm and 320 nm. The results showed that polyphenols in apple were seven kinds of neutral polyphenols and three kinds of acidic polyphenols, the recovery of the polyphenols was in the range of 95%~104% and RSD were lower than 2.2%. This method was rapid, sensitive, simple, accurate and less impurity interference, and ten kinds of polyphenols peaks were separated well.