| This study investigated antioxidant and antiproliferative activities of medicinal herb feverfew (Tanacetum parthenium) and characterized its major bioactive constituents. Influences of the solvent, microwave-assisted and enzyme-assisted extraction methods on parthenolide yield and bioactivities were also studied.; Parthenolide, camphor, chrysanthenyl acetate, luteolin, apigenin, chlorogenic acid, caffeic acid, 3,5-di-O-caffeoylquinic acid, 3,4-di- O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid were identified in golden feverfew using chromatography, mass spectrometry and nuclear magnetic resonance. Golden feverfew extracts possessed strong DPPH free radical scavenging activity and moderate Fe2+-chelating capacity. The 3,5-di-O-caffeoylquinic acid was a major contributor to the high DPPH scavenging activity of feverfew extracts. Luteolin and four other phenolic acids also showed strong DPPH scavenging activity, while parthenolide and camphor exhibited weak DPPH scavenging activity. Moderate Fe2+ -chelating capacity was associated with parthenolide, luteolin and apigenin.; Golden feverfew ethanolic extracts inhibited the growth of all three cancer cells lines studied, with EC50 against Hs605T, MCF-7 and SiHa at 1.5 mg/mL, 2.1 mg/mL, and 0.6 mg/mL, respectively. Among the tested constituents of feverfew (i.e., parthenolide, camphor, luteolin and apigenin), parthenolide showed the highest inhibitory effect with EC50 against Hs605T, MCF-7 and SiHa of 2.6 mug/mL, 2.8 mug/mL and 2.7 mug/mL, respectively. Apigenin and luteolin had moderate to weak synergistic effects with parthenolide on inhibition of three cancer cell. Adding vitamin E to common feverfew extracts or parthenolide did not show any synergistic efficacy to inhibit the growth of Hs605T and SiHa cells, but promoted the growth of MCF-7 cells.; High parthenolide yield (0.22+/-0.03%) was obtained when using 80% ethanol and bar-stirring extraction for 10 min. Microwave-assisted aqueous extraction was effective in increasing yields of parthenolide, phenolics, and chlorogenic acid when compared to hot water extraction. This extraction had no effect on DPPH free radical scavenging and Fe2+-chelating activities of feverfew. Adding enzyme mixtures enhanced cell wall degradation in all tested particle sizes (<850 mum) but decreased yields of total phenolics and parthenolide when compared with controls. Particle size affected parthenolide yield, with the highest yields observed in the smallest particle size (<105 mum) in both enzyme treatments and controls. |
