Abstract: In this study, we optimized the simultaneous separation and purification of forsythiaside A, phillyrin and rutin from an ethanolic extract of Forsythia suspensa leaves. These target compounds were quantitatively determined by high performance liquid chromatography (HPLC). Different types of macroporous adsorption resin were compared for their abilities to separate and purify three active components from Forsythia suspensa leaves. AB-8 resin was selected as the best one, and the optimum chromatographic conditions on this adsorbent were obtained as follows: sample-to-resin ratio, 1.5:1 (g/g); sample loading flow rate, 2 bed volumes (BV)/h; sequential elution with 8 BV of deionized water, 6 BV of 30% ethanol and 6 BV of 50% ethanol at a flow rate of 3 BV/h. Further purification of forsythiaside A was carried out using a C18-silica gel column by reversed-phase chromatography, while purified phillyrin and rutin were obtained by precipitation after standing. After purification, the purity of forsythiaside A and rutin was more than 97%, and that of phillyrin was over 95%. In conclusion, under the optimized conditions, three effective components of high purity were obtained from Forsythia suspensa leaves. This study may be helpful for the comprehensive utilization and industrialization exploitation of Forsythia suspensa leaves.

Key words: Forsythia suspensa leaves, forsythoside A, rutin, phillyrin, extraction conditions