oxidative stress

The bacteria Azospirillum brasilense, used as biofertilizers, have a signifi cant positive eff ect on the growth and development of plants. The genome of the strain A. brasilense Sp7 is represented by a chromosome and numerous plasmids with molecular weight of 90, 115, and over 300 MDa. Genomic rearrangements that cause changes in the “plasmid profi le” can contribute to the formation of subpopulations or phenotypic variants in a bacterial population. There is little data on the role of such rearrangements in the adaptation of A.

The paper presents the results of an experimental study of VHF band electromagnetic field on the intensity of lipid peroxidation and total antioxidant activity of rats blood serum. As a result of the conducted research it were revealed valid changes in the concentration of diene conjugates, ketodienes and of the activity of the antioxidative system at different duration of exposure.

The goal of this research was lipid peroxidation process assessment for different levels of ultrahigh frequency electromagnetic field and different time exposure. There were animal 171 MHz one time exposures during 1 and 3 hours. In the blood serum of exposed animals the malondialdehyde concentration evaluated the lipid peroxidation process. The research results shown the statistically significant electromagnetic field biological effects as for maximum field strength 1 hour exposure, as lower field strength 3 hours exposure.

The effect of heavy metal ions (Ni2+, Zn2+, Cu2+, Pb2+)  in concentrations of 10 ?M, 0.1 ?M and 1 mM on the rate of lipid peroxidation (LPO) has been studied in the 7-day-old seedlings of cucumber (Cucumis sativus L.) and radish (Raphanus sativus L.). It was revealed that Ni2+ and Cu2+ ions induced oxidative stress in plant cells, but Pb2+ and Zn2+ ions did not have toxic effects. The heavy metals effect on LPO increasing was as follows: Zn2+ < Pb2+< Ni2+ < Cu2+ for cucumber plants; Pb2+< Zn2+ < Cu2+ < Ni2+ for radish plants.