Simple Method for Analysis of Chlorogenic Acid in Foods by DEAE-Toyopearl^TM Column

Abstract

A simple column chromatographic procedure for analysis of chlorogenic acid analogue (Chl) was developed. Phenolic fraction containing Chl was extracted from plant food with 0.01M acetate buffer (pH 5) and the fraction was applied to a DEAE-Toyopearl_TM column (11×30mm). The column was washed throughly with 0.1M phosphate buffer (pH 7), followed by elution of Chl adsorbed in the Toyopearl_TM gel with 0.1N hydrochloric acid. The content of Chl was obtained from the absorbance at 325nm of the eluent spectrophotometrically, or was estimated from the absorbance at 520nm of a red solution formed by the reaction between Chl adsorbed in the above column and Hoepfner reagent colorimetrically. In several foods, slightly lower analytical value of Chl was found by the latter method than that by the former one in this DEAE-Toyopearl_TM column chromatographic procedure. The recovery rate of Chl by the spectrophotometric method was ranged from 99 to 102%.