Antioxidant screening of some medicinal plants of Iran

One of the most reactive and dangerous agents for the living cells is reactive oxygen free radical species (ROS). When there is an imbalance between ROS generating and scavenging systems (oxidative stress), tissue damages will appear in human body such as degenerative disorders of CNS like Alzheimer's disease. Recently, a high interest in medicinal plants containing antioxidants has been increased because of lower side effects, higher water solubility and more potency. The objective of this work was to carry out a screening test to find the most antioxidant activity in plants containing high levels of flavonoids (as reported in a phytochemistry research by the authors before). A total methanolic extract of plants was prepared and dried for evaluation of antioxidant activity. Antioxidant activity of the extracts was evaluated by using diphenylpicryl hydrazyle (DPPH) added to different extract concentrations. Absorption of DPPH decreased if there was an antioxidant activity. Some medicinal plants belong to polygonaceae family showed antioxidant activity. We concluded that some of the plants showing antioxidant activity contained high levels of flavonoids (as showed before by the authors) and so it is under isolating and identifying the chemical struchres of active components.