Abstract
Berberis species have been used extensively as raw material in various herbal medicines. In this work, a fast and sensitive method based on reversed-phase high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (HPLC-ESI-QTOF-MS/MS) was used to assist the distribution and discrimination study of bioactive compounds from Berberis species such as B. aristata, B. asiatica, B. chitria, B. jaeschkeana, B. koehneana, B. lyceum, B. petiolaris and B. pseudoumbellata. The HPLC separation was performed on a Thermo Betasil C8 column (250 mm x 4.5 mm, 5μ) using gradient elution with a mobile phase of 0.1% aqueous solution of formic acid (v/v) and acetonitrile. The high resolution (HR) and collision induced dissociation (CID) mass spectrometry experiments were conducted in order to provide molecular-mass information and MS/MS fragmentation patterns of the compounds for structural elucidation. A total of 59 compounds were tentatively identified and characterized including three acids, forty-one alkaloids and twelve flavonoids using seventeen reference standards for authentication. Principle component analysis (PCA) was also applied to discriminate eight Berberis species according to their plant parts i.e., leaf, stem and root. The highest total content of identified compounds was detected in the root of all the Berberis species wherein alkaloids were predominant.