Free radical formation, particularl

Free radical formation, particularly the formation of the series of oxygen free radicals mentioned above, is associated with normal metabolism in aerobic cells, and different types of oxidant damages occur in humans due to these species (Giri et al., 2012). Oxygen consumption during cell growth generates these species, and lipid-like molecules can produce new radicals, hydroperoxides and secondary oxidation products (Torel, Cillard, & Cillard, 1986). This group of radicals is likely cytotoxic toward biological systems. Fortunately, flavones and other polyophenols possess important antioxidant activity against these radicals due to the redox properties of their phenolic hydroxyl groups and the structural relationships between different parts in their chemical structures.