Abstract

Illicium verum has been widely used in many Asian countries as a spice and pharmaceutical treatment for many diseases. In this study, the antioxidant properties of the ethanol extracts fractionated by hexane, ethyl ether, chloroform and ethyl acetate, and supercritical CO₂ extracts of the plant were evaluated using 1,1-diphenyl-2-picryhydrazyl (DPPH) radical scavenging effect, the total equivalent antioxidant capacity and a reducing power assay. In addition, the amount of total phenolic content and the flavonoid content were also determined. The ethyl acetate fractions contained substantially higher levels of total phenolics (4.5 g gallic acid / 100 g dry weight) and total flavonoids (6.9 g quercetin/100 g dry weight) than the other extracts, and possessed significant antioxidant activities. The chemical components of the various extracts were analyzed by gas chromatography-mass spectrometry (GC-MS); anisyl acetone and anisyl aldehyde were evidenced to provide the slight antioxidant activities. Based on the results, it can be concluded that the ethyl acetate extracts of I. verum show a marked antioxidant potential and that they could be developed as a natural source of antioxidants.

Key words: Chinese medicines, Illicium verum, antioxidant activity, supercritical CO₂extraction.

Abbreviation

 DPPH, 1,1-Diphenyl-2-picryhydrazyl; ROS, reactive oxygen species; BHT,butylated hydroxytoluene; SFE, supercritical fluid extraction; TEAC, trolox equivalent antioxidant capacity; ABTS, 2,2-azinobis-3-ethylbenzthiazoline-6-sulfonic acid; UV, ultraviolet; TLC, thin-layer chromatography; DW, dry weight; GAE, gallic acid equivalent; GC-MS, gas chromatography-mass spectrometry.