RESUMEN
Antioxidant activity of natural compounds in food and in dietary supplements plays an important role in healthy life. Scientific evidences suggest that antioxidants reduce the risk for chronic diseases including cancer, diabetes mellitus and heart diseases. The antioxidant activity of wild Cyclamen persicum, Malva sylvestris and Urtica pilulifera leaves and their cultivated species were studied using 2, 2-diphenylpicrylhydrazyl (DPPH) radical scavenging activity and compared to Trolox antioxidant activity. The exhaustive extractions yields for these samples were estimated by using polar and nonpolar solvents. The results showed that the wild Cyclamen persicum, Malva sylvestris and Urtica pilulifera leaves have higher exhaustive extraction yield and as well the higher antioxidant activity (IC50) comparing with their cultivated species. Both of cultivated, as well the wild natural growing forms of Cyclamen persicum, Malva sylvestris and Urtica pilulifera are a good source for natural foods supplements, pharmaceutical industry purposes and for organic food rich with antioxidant compounds.
RESUMEN
The photodynamic action of riboflavin is generally considered to involve the generation of reactive oxygen species [ROS], the production of which is enhanced when Cu [II] is present in the reaction. In the present study we report that photoactivated riboflavin caused lipid peroxidation in fresh human red blood cells [RBC] in a time dependent manner. Addition of Cu [II] and sodium azide enhanced the lipid peroxidation in RBC. Bathocuproine, a specific Cu [I] sequestering agent, when present in the reaction, inhibited the lipid peroxidation to about 70%. Free radical scavengers like superoxide dismutase, potassium iodide, mannitol, [Beta]-carotene and thiourea inhibited the lipid peroxidation to different extents. These results suggest that lipid peroxidation in human RBC is basically a free radical mediated reaction