Leaf aging and lipid peroxidation: The role of the antioxidants vitamin C and E

Abstract

To study age‐related peroxidation in annual beech ( Fagus silvatica Mill.) leaves and perennial fir ( Abies alba Mill.) needles, the concentration changes of the antioxidants vitamin C (ascorbic acid) and vitamin E (α‐tocopherol) present in leaves and needles were determined, and the formation of thiobarbituric acid reactants was measured as an index of age‐related lipid peroxidation. With age, the content of the lipid‐soluble antioxidant vitamin E increased, and the increase was higher in beech leaves than in fir needles. A comparable age‐dependent increase of the vitamin C content was found neither in leaves nor in needles. The concentration ratio of the vitamin C to the vitamin E present in leaves and needles, which determines the potency of the anti oxidative system consisting of both vitamins, declined with age. This decline was directly related to a higher peroxidation of lipids. The extent of age‐related peroxidative damage of cells seems to be controlled by the potency of anti oxidative systems.