Abstract

A reliable solid-phase extraction – high-performance liquid chromatography (SPE-HPLC) method for the determination of flavonoids in European Bupleurum species B. baldense Turra and B. affine Sadler was developed. Extraction of aerial parts by ultrasound with 80% aqueous methanol and fractionation of flavonoids by means of SPE allowed a good recovery of analytes between 99 and 104%. The subsequent HPLC separation of the flavonoids was performed on a Luna C18 column using gradient elution and UV detection. The optimized SPE-HPLC method was validated for precision, linearity, accuracy, recovery, limit of detection and limit of quantification. The precision of the entire analytical procedure was < 2%. The total amount of assayed flavonoids was 11.53 mg/g dry weight (B. affine) and 39.16 ± 0.92 mg/g (B. baldense). Rutin was the dominant flavonol glycoside in B. baldense being present at 28.63 ± 1.57 mg/g, whilst B.affine demonstrated lower levels of flavonoids.