Oxidation of lecithin in the presence of dihydroquercetin and its complex with divalent iron ions

The ability of the flavonoid dihydroquercetin to prevent or accelerate the accumulation of reactive oxygen species and the metabolites of oxidative stress, carbonyl compounds has been studied. It has been shown on a model of oxidation of lecithin that dihydroquercetin exhibits a prooxidant effect in the alkaline region of pH, whereas at neutral and acidic pH values dihydroquercetin is an effective antioxidant. In the presence of ferrous iron ions, which catalyze the Fenton reaction, dihydroquercetin forms a complex with metal that shows the antioxidant activity in the region of high pH values. It has been found that the oxidation of lecithin in the presence of 20–200 μM ferrous iron is inhibited by dihydroquercetin to a concentration of 3.2 mM. At higher concentration of dihydroquercetin in the presence of ferrous iron, accumulation of malonic dialdehyde occurs, indicating the presence of the prooxidant activity of dihydroquercetin.     

Photoregulation of the Cytoplasmic PGA Dehydrogenase Complex in Wheat Leaves

Russian Journal of Plant Physiology - Experiments were performed with 10-day-old seedlings of wheat (Triticum aestivum L.) grown on sand saturated with Knop’s solution at a temperature of...     

Effect of Phytochrome Deficit on Activity of Ascorbate Peroxidase and Phenylalanine Ammonia-Lyase and Expression of Genes APX1, tAPX,sAPX, and PAL in the Leaves of Arabidopsis thaliana Plants Exposed to UV-A and Red Light

Russian Journal of Plant Physiology - Effect of UV-A radiation (10 W/m2, 2 h) and modifying effect of brief exposure to red light (RL) (1.8 W/m2, 20 min) on photochemical activity of photosystem II...     

Response of photosynthetic apparatus in Arabidopsis thaliana L. mutant deficient in phytochrome A and B to UV-B

Photosynthetica - The effects of UV-B radiation (1 W m–2, 1 and 2 h) on PSII activity, chloroplast structure, and H2O2 contents in leaves of 26-d-old Arabidopsis thaliana phyA phyB double...