Jóźwiak Weronika, Politycka Barbara
Department of Plant Physiology, Poznań University of Life Sciences, Poznań 60-637, Poland.
Plants (Basel). 2019 Jul 11;8(7):217. doi: 10.3390/plants8070217.
The aim of the study was to evaluate the antioxidant activity of selenium in the roots of L. seedlings pre-treated with selenium (Se) in the form of sodium selenite at concentrations of 1, 5, and 10 µM, and then subjected to a water deficit (WD). It has been hypothesized that Se, in low concentrations, alleviates an oxidative stress caused by a WD in the cucumber roots. A WD was introduced by the surface dehydration of roots. The aim of the research was to compare the changes accompanying oxidative stress in plants growing in the presence of Se and in its absence. The study concerns the generation of reactive oxygen species (ROS)-superoxide anions (O), hydrogen peroxide (HO), and hydroxyl radicals (OH)-as well the activities of the antioxidant enzymes lowering the ROS level-ascorbate peroxidase (APX), peroxidase (POX), catalase (CAT), and superoxide dismutase (SOD). A WD caused oxidative stress, i.e., the enhanced generation of ROS. Selenium at the concentrations of 1 and 5 μM increased the tolerance of cucumber seedlings to oxidative stress caused by a WD by increasing the activities of the antioxidant enzymes, and it also limited the damage of plasma membranes as a result of the inhibition of lipid peroxidation.
本研究的目的是评估以亚硒酸钠形式存在的硒（Se）在浓度为1、5和10μM时对黄瓜幼苗根系进行预处理，然后使其遭受水分亏缺（WD）后，硒的抗氧化活性。据推测，低浓度的硒可减轻黄瓜根系因水分亏缺引起的氧化应激。通过根系表面脱水引入水分亏缺。本研究的目的是比较在有硒和无硒情况下生长的植物中伴随氧化应激的变化。该研究涉及活性氧（ROS）——超氧阴离子（O）、过氧化氢（HO）和羟基自由基（OH）的产生，以及降低ROS水平的抗氧化酶——抗坏血酸过氧化物酶（APX）、过氧化物酶（POX）、过氧化氢酶（CAT）和超氧化物歧化酶（SOD）的活性。水分亏缺引起了氧化应激，即ROS的生成增加。1和5μM浓度的硒通过提高抗氧化酶的活性，增加了黄瓜幼苗对水分亏缺引起的氧化应激的耐受性，并且由于抑制脂质过氧化，还限制了质膜的损伤。
