Phytochemical investigations of Polygonum aviculare, Agrimonia eupatoria and Lythrum salicaria by HPLC-DAD-MS3-CAD method – application of corona charged aerosol detection (CAD) for analysis of plant phenolics

Abstract

The examination and standardization of traditionally used plant materials is often based on old-fashion methods that seem to be not fully reliable. The HPLC coupled with DAD and mass spectrometer method is a powerful tool for the proper identification of plant phenolics. Charged aerosol detection (CAD) in liquid chromatography is a relatively new technic introduced in 2002 [1]. It has been shown that the response of CAD does not depend on the structure or molecular mass of analyzed substances so it can be utilized as universal response device for HPLC. There are a few reports on possible applications of CAD for the analysis of plant extracts. The aim of the study was to investigate the chemical composition of chosen plant materials using HPLC-DAD-MS3 method and to quantify their major constituents using CAD. The application of CAD as a universal response detector for plant phenolics was also evaluated. The chemical investigation of Polygoni avicularis herba, Agrimoniae eupatoriae herba and Lythri herba has shown that all three plant materials are a rich source of plant phenolics including flavonoids, tannins and phenolic acids [2 – 3]. Most of detected compounds were fully identified showing that examined plant materials contain constituents that have not been previously detected and some of them have been isolated as new natural products. The quantification of major compounds of A. eupatoria and L. salicaria with CAD showed that the in the case of plant phenolics the response of CAD may vary significantly depending on the compound analyzed [3 – 4]. The proper investigation of CAD response for chemical standards and analysed compounds should be carried out and must not be omitted.