Antioxidant activity of Knipholone anthrone

作者：Habtemariam Solomon^*

来源：Food Chemistry, 2007, 102(4): 1042-1047.

DOI：10.1016/j.foodchem.2006.06.040

• Knipholone anthrone
• Kniphofia foliosa
• antioxidant activity
• DPPH
• reducing power
• superoxide anion
• hydroxyl radical
• iron chelation
• DNA damage

Knipholone anthrone (KA), isolated from an Ethiopian medicinal plant, Kniphofia foliosa, Hochst (Asphodelaceae) has been shown to display a potent antiprotozoal activity and a relatively little cytotoxic effect on mammalin cells. In the present study, the antioxidant potential of KA was assessed using a variety of in vitro assay models. KA displayed a concentration-dependant scavenging effect against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. The IC(50) values obtained for KA and the positive control (-)-epicatechin (EC) in the DPPH assay were 22 +/- 11.5 and 8.7 +/- 0.9 mu M (mean +/- SEM; n = 3 separate experiments), respectively. KA displayed a better activity than EC in scavenging superoxide anions and preventing deoxyribose degradation by hydroxyl radicals. KA appeared to form a complex with Fe(2+), displayed a concentration-dependant reducing power, and also protected (at concentrations of 4.4 mu M and above) isolated DNA from damage induced by Fenton reaction-generated hydroxyl radicals.

• 出版日期2007