The present study was carried out to investigate the antioxidant effects of aqueous extract of Raphanus raphanistrum L. (Brassicaceae) aerial parts by using various in vitro systems. The antioxidant activity of the plant was determined by the 2,2-diphenyl-l-picrylhydrazyl (DPPH) free radical scavenging test, flow injection analysis-luminol chemiluminescence (FIA-CL) and thiobarbituric acid (TBA) assays. To estimate the total phenolic content, the assay using Folin-Ciocalteu reagent was used. In addition, mineral composition of the raw plant was examined by atomic absorption spectroscopy. Raphanus raphanistrum aqueous extract was found to possess DPPH free radical scavenging activity (IC50=8-78 mg/mL), inhibitory effect on H2O2- and HOCl-luminol chemi luminescence (-logIC50=3.73 and 3.1x10-2 mg/ml.), and inhibitory activity toward lipid peroxidation (IC50=63.33 ug/ml.) compared to the references. The total phenolic content was 43.32 mg gallic acid g extract. According to our results of mineral composition, the raw plant has lower amount of toxic elements (Pb, Cd and A!) than permissible level recommended by WHO. In addition, Ca level was found to be higher (16 mg/g) than daily intake of man. These observations suggest that Raphanus raphanistrum have a potential source of antioxidant and minerals of natural origin.

Keywords: Brassicaceae, Raphanus raphanistrum L., Antioxidant activity, Radical scavenging activity, Flow injection analysis, Lumino1 chemiluminescence, Mineral.