Characterisation of hydrolysable tannins from leaves of Betula pubescens by high-performance liquid chromatography-mass spectrometry

A high-performance liquid chromatography-electrospray ionisation mass spect rometry (HPLC-ESI-MS) method, assisted by diode array detection, for the ch aracterisation of individual hydrolysable tannins in birch leaves was devel oped. With the method, it was found that birch (Betula pubescens) leaves co ntained an exceptionally complex mixture of hydrolysable tannins; 14 gallot annins and 20 ellagitannins were identified. The developed HPLC-ESI-MS meth od allows the qualitative and quantitative determination of individual gall otannins and ellagitannins directly from crude birch leaf extract. This is important in studying ecological functions of these phenolic compounds, esp ecially their role in the resistance of birch leaves against insects. (C) 1 999 Elsevier Science B.V. All rights reserved.