Identification of antioxidative ingredients from feverfew (Tanacetum parthenium) extract substantially free of parthenolide and other alpha-unsaturated gamma-lactones

Abstract

Extract of feverfew (Tanacetum parthenium) has anti-infl ammatory effect with various therapeutic benefi ts. Alpha-unsaturated gamma-lactones including parthenolide were recognized as part of the major active ingredients but with undesirable allergic reactions. In this research paper, feverfew extract substantially free of parthenolide and other alpha-unsaturated gamma-lactones was investigated. We are reporting the identifi cation of more than twenty ingredients from this feverfew extract. The ingredients mainly include caffeoyl derivatives and fl avonoids. Four ingredients, caffeic acid methyl ester (2), cynarin (13), 4-methoxyl caffeic acid (22) and 3,4-dimethoxyl caffeic acid (27), were discovered in feverfew for the fi rst time. The identifi cation works were performed primarily using HPLC-UV and HPLC-APCI-MS analyses and comparing with reference compounds. Ingredients caffeic acid (1), caffeic acid methyl ester (2), quercetagetin 3, 6-dimethyl ether (3), apigenin (4), and santin (6), were isolated by semi-preparative HPLC; and their structures were further confi rmed by NMR analyses. The application of APPI-MS on the analyses of 1 and 2 enabled successful molecular weight determination and eliminated lingering ambiguity caused by weak signals from APCI-MS detection. The extract of feverfew also demonstrated considerably high antioxidant capacity using a DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging model likely due to its caffeoyl derivatives and fl avonoid ingredients with phenolic moieties to contribute to its pharmacological benefi ts.