Chlorophenols induce lipid peroxidation and change antioxidant parameters in the leaves of wheat (Triticum aestivum L.)

In this work, changes in superoxide dismutase (SOD), catalase (CAT) and guaiacol. peroxidase (POD) activity were determined in the leaves of wheat (Triticum aestivum L.) exposed to 2,4-dichtorophenot (2,4-DCP) and pentachlorophenol (PCP). We analyzed the content of free phenols, the level of lipid peroxidation, and also the oxidation of dihydrorhodamine 123 by 2,4-DCP and PCP. Chlorophenots were spiked to soil in concentrations of 0.5 and 5.0 mg kg(-1). Plant seeds were raised in plastic pots containing soil at a temperature of 25 degrees C with a 16-h photoperiod and irradiance of 250 mu mol m(-2) s(-1). The leaves were harvested on the third, sixth and twelfth days of the experiment. The inhibition of SOD activity in the leaves of wheat was observed for 2,4-DCP and PCR 2,4-DCP and PCP induced changes in CAT activity with a stronger effect for PCR The compounds markedly increased guaiacol POD activity during 12d of the exposition of wheat to their action. The increase in free phenol content was observed both for 2,4-DCP and PCR Chlorophenots also induced a powerful lipid peroxidation process between the third and sixth days of the experiment. A higher concentration of chlorophenols used in our study induced greater changes in all of the investigated parameters. 2,4-DCP and PCP oxidized the fluorescent probe dihydrorhodamine 123 - in the concentrations of 5 and 1 ppm, respectively, and the addition of magnesium ions enhanced the oxidative capacity of the examined xenobiotics. (C) 2008 Elsevier GmbH. All rights reserved.