Comparison of Radix angelicae pubescentis and substitutes -: Constituents and inhibitory effect on 5-lipoxygenase and cyclooxygenase

Various samples of Radix Angelicae pubescentis (Duhuo) and substitutes from the genera Angelica, Heracleum (Umbelliferae), and Aralia (Araliaceae) were analyzed for their constituents and inhibitory effect on cyclooxygenase (COX-1) and 5-lipoxygenase (5-LO). HPLC analysis showed that osthol, columbianedin, columbianetin acetate, and angelol-type coumarins are the principal constituents of the n-hexane and dichloromethane extracts of the roots of Angelica pubescens f. biserrata The constituents of the substitutes from Angelica and Heracleum species were found to be mainly furanocoumarins and falcarindiol. No coumarins were detected in Aralia cordata. The presence of fatty acids (linoleic acid) could be confirmed by GC in Duhuo and the substitutes. All the species showed inhibitory effects on COX-1 and 5-LO. Linoleic acid turned out to be the most active constituent in the extract exerting COX-1 inhibition and also had strong inhibitory activity on 5-LO. Osthol was another major inhibitor of 5-LO in Radix Angelicae pubescentis, while in the substitutes falcarindiol was mainly responsible for the 5-LO inhibitory effect, except in Aralia cordata which also contained other polyacetylene derivatives.