HPLC Analysis of Flavonoids from the Aerial Parts of Bupleurum Species

AimTo establish a quantitative analysis method with HPLC-UV for simultaneous determination of flavonoids in the aerial parts of Bupleurum, to investigate the content and distribution of flavonoids in different species of Bupleurum with the established method for quality control.MethodA rapid and accurate HPLC-UV method was developed and validated for the quantitative determination of twelve flavonoids, (+)-catechin (1), apigenin-6, 8-di-C-glucopyranoside (2), quercetin-3-O-rutinoside (3), kaempferol-3, 7-di-O-rhamnoside (4), quercetin-3-O-arabinoside (5), quercetin-3-O-rhamnoside (6), 7-hydroxyl-2, 5-dimethyl-4H-chromone (7), acacetin-7-O-rutinoside (8), kaempferol-7-O-rhamnoside (9), quercetin (10), kaempferol (11) and isoramnetin (12). The subsequent HPLC separation and quantification was achieved in 60 minutes using a Shimpack ODS C18 column and at 254 nm. The mobile phase comprised solvent A (0.1% formic acid aqueous, V/V, pH 2.6) and solvent B (acetonitrile) and gradient elution mode was applied. This established method was therefore applied to determine the amounts of flavonoids in twenty-eight samples collected from different regions in China.ResultThe linear regression analytical data for the calibration plots showed a good linear relationship with r2 > 0.9995 within the test ranges. The average recovery was from 97.10 to 102.86% indicating good accuracy. It was successfully applied to quantify twelve flavonoids in different samples.ConclusionIt is the first time to establish a quantitative method to investigate the content and distribution of flavonoids in different species of Bupleurum.