Analysis of quinic acid esters of hydroxycinnamic acids in plant material by capillary gas chromatography and high-performance liquid chromatography

Abstract

Capillary gas chromatographic (GC) and high-performance liquid chromatographic (HPLC) methods for separation and determination of cis and trans isomers of nine caffeoyl-, p-coumaroyl- and feruloylquinic acids in plant extracts are presented and compared. GC analysis requires highly deactivated SE-30 capillaries because of the sensitivity of the silylated compounds and the high temperatures involved. The production of these capillaries is described. HPLC analysis is performed with an RP-18 column and a gradient elution with 2% acetic acid-methanol. Both methods allow the separation opf the trans isomers and most of the cis isomers. For the various samples, quantitatives results of GC and HPLC separation agree well. © 1982.