In vitro antioxidant properties of Helichrysum arenarium (L.) Moench.

The choleretic, hepatoprotective and detoxifying activities of the inflorescence of Helichrysum arenarium (L.) Moench (everlasting, immortelle: Asteraceae-Helichrysi flos syn. Stoechados flos) have been known for a long time from herbal medicine in Hungary. Antioxidant properties of its main phenolics, flavonoids, are supposed to be responsible for these effects. The aim of this study is to verify the antioxidant properties of the lyophilized water extracts from inflorescences, and to define the total polyphenol and flavonoid contents in Helichrysi flos water extracts as well as in lyophilized water extracts. The hydrogen-donating ability and the reducing power property of the lyophilizates were determined spectrophotometrically; their OH&z.rad; scavenging activity was measured, in the H(2)O(2)/OH&z.rad;-luminol-microperoxidase system, by a chemiluminometric method. Results were compared with the activity of the flavonoid silibinin, the main agent of the well-known milk thistle (Silybum marianum L.).