Strictinin as an efficient antioxidant in lipid peroxidation

The antioxidant effect of strictinin (SOH), which was extracted from green tea leaves, against the peroxidation of linoleic acid in sodium dodecyl sulfate (SDS) and cetyl trimethylammonium (CTAB) micelles, against the peroxidation of low-density lipoprotein (LDL) and against oxidative hemolysis of human red blood cells (RBCs), has been studied. The peroxidation of linoleic acid and LDL, and oxidative hemolysis of RBCs were initiated thermally by a water-soluble azo initiator 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH), and the reaction kinetics in micelles and LDL were monitored by uptake of oxygen. The synergistic antioxidant effect of SOH with alpha-tocopherol (Vitamin E) was also studied by following the decay kinetics of alpha-tocopherol. Kinetic analysis of the antioxidation process demonstrates that SOH, used either alone or in combination with alpha-tocopherol, is an effective antioxidant against lipid peroxidation, but its effects significantly depend on the reaction medium. (C) 2004 Elsevier Ireland Ltd. All rights reserved.