Background. The oxygen is the ultimate electron acceptor in the electron flow system that produces energy. Problems appears when the electron flow becomes uncoupled thus, generating free radicals. While the majority of processes require oxygen, the last is a highly reactive molecule that can damage cells by producing reactive oxygen species, such as hydroxyl radical, superoxide radical, hydrogen peroxide and hypochlorous acid, all together defined as triggers of oxidative stress. The last is involved in many types of pathologies, such as cancer, atherosclerosis and rheumatic arthritis. Antioxidants can stop formation of free radical by giving hydrogen atoms or scavenging them. The antioxidant can be defined any molecule capable of preventing or blocking oxidation of lipids, proteins and nucleic acids. The reduced glutathione (GSH), as well enzymes, glutathione peroxidase (GPO), glutathione reductase (GR) and glutathione S-transferase (GST) represent antioxidants which prevent the formation of new free radicals, converting them into less harmful molecules. The present study was conducted to assess the antioxidant activity of Taraxacum officinale (TO) ethanolic extracts with different bioactive contents. This experiment was conducted with extracts prepared from dandelion (Taraxacum officinale F. H. Wigg) leaves. A series (10%, 20%, 25%, 40%, 50% and 80%) of ethanolic extracts were made. The influence of TO extracts on RBC’s GPO, GR, GST, glutathione (GSSG, GSH and total-GSH) and thiols (native and total) was evaluated by measuring absorbance spectrophotometrically. Conclusions. Taraxacum officinale ethanolic extracts exhibit a strong antioxidant activity. This plant is capable of preventing damage of cells during oxidative stress process, by using different targets of glutathione system. But, this activity depends of ethanol concentrations, maybe due to different bioactive content.
Catalase-Like Antioxidant Activity is Unaltered in Hypochlorous Acid Oxidized Horse Heart Myoglobin
