Analysis of Phenolic Acids by High Performance Liquid Chromatography Using a Step-Wise Gradient

Abstract
A high performance liquid chromatographic method for analyzing phenolic acids on reverse phase C-18 is described. Twelve substituted benzoic and cinnamic acid derivatives as well as the parent acids were resolved in less than 25 min. Separation was achieved by using a step-wise gradient of three different solvent systems and by adding ammonium acetate for preventing intramolecular hydrogen bonding of the acids. The applicability of the described m ethod to crude plant extracts is demonstrated with Adenostoma fasciculatum, Adenostoma sparsifolium and Phyllospadix scouleri. The percent composition of the phenolic acids within the three extracts is given.