Analysis of Hydroxycinnamic Acids in Roots of Japanese Radish

Raphanus satiuus L.

Abstract

The kind and amount of hydroxycinnamic acids occurring in the roots of radish (Raphanus satiuus L.) cultivated in Japan were investigated. In the ethyl acetate extracts of roots prepared under the acidic condition, malic acid esters of p-coumaric acid and ferulic acid were identified as main hydroxycinnamic acids. In quantitative analysis, the esters which were partially purified by C₁₈ SEP-PAK cartridges were converted into liberated form by an alkaline-hydrolysis, and HPLC analysis was accomplished. In 13 varieties of radish, the amounts of p-coumaric acid and ferulic acid contained as malic acid ester were 1.26-8.58mg per kg and 0.24-1.12mg per kg, respectively.