Brassinosteroid alleviates polychlorinated biphenyls-induced oxidative stress by enhancing antioxidant enzymes activity in tomato
Brassinosteroid alleviates polychlorinated biphenyls-induced oxidative stress by enhancing antioxidant enzymes activity in tomato
复制标题
油菜素类固醇通过增强番茄抗氧化酶活性减轻多氯联苯诱导的氧化应激
DOI：
10.1016/j.chemosphere.2012.11.041
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发表时间：
2013-03-01
期刊：
影响因子：
8.8
通讯作者：
Yu, Jing-Quan
中科院分区：
文献类型：
--
作者：
Ahammed, Golam Jalal;Ruan, Yi-Ping;Yu, Jing-Quan
多氯联苯（PCBs）是大气中常见的持久性有机污染物。植物修复空气中的多氯联苯是一个新兴的新概念，以尽量减少潜在的人类接触。然而，大气中的多氯联苯对植物生长，光合作用和抗氧化防御系统的影响知之甚少。已报道，类维生素B1能缓解不同的非生物胁迫，包括有机污染物诱导的胁迫。因此，我们研究了PCBs和24-表油菜素（EBR）对番茄生物量积累、光合机制和抗氧化系统的影响。PCBs（0.4，2.0和10 μ g/l）喷雾处理显著降低了水稻的干重、光合作用和叶绿素含量，且呈剂量依赖关系。多氯联苯对光合作用的抑制既有气孔因素也有非气孔因素。同样，PSII的最大光化学效率（Fv/Fm）、PSI的量子效率（Fv/Fm）、PSII的最大光化学效率（Fv/Fm）、光化学（Phi（PSII））和光化学猝灭系数随PCBs浓度的增加而降低，表明PCBs诱导了光抑制。增加积累的H2 O2和O-2（中心点）-伴随着高脂质过氧化证实发生氧化应激多氯联苯暴露。同时，抗氧化酶活性降低暴露于多氯联苯。叶面施用EBR（100 nM）通过提高Fv/Fm、Phi（PSII）和qP来增加生物量、光合能力、叶绿素含量并减轻光抑制。EBR通过诱导抗氧化酶的活性，显著降低有害活性氧的积累和脂质过氧化作用。我们的研究结果表明，EBR对PCBs胁迫的保护作用，这可能会加强植物修复方法，提高植物的耐受性。(c)2012爱思唯尔有限公司保留所有权利。
Polychlorinated biphenyls (PCBs) are persistent organic pollutants often found in the atmosphere. Phytoremediation of airborne PCBs is an emerging new concept to minimize potential human exposure. However, effects of atmospheric PCBs on plant growth, photosynthesis and antioxidant defence system are poorly understood area. Brassinosteroids have been reported to alleviate different abiotic stresses including organic pollutants-induced stress. Hence, we studied the effects of PCBs and 24-epibrassinolide (EBR) on biomass accumulation, photosynthetic machinery and antioxidant system in tomato plants. PCBs (0.4, 2.0 and 10 mu g/l) mist spray significantly decreased dry weight, photosynthesis, chlorophyll contents in a dose dependent manner. Both stomatal and non-stomatal factors were involved in PCBs-induced photosynthetic inhibition. Likewise, the maximal photochemical efficiency of PSII (Fv/Fm), the quantum efficiency of PSI! photochemistry (Phi(PSII)) and photochemical quenching coefficient were increasingly decreased by various levels of PCBs, suggesting an induction of photoinhibition. Increased accumulation of H2O2 and O-2(center dot)- accompanied with high lipid peroxidation confirmed occurrence of oxidative stress upon PCBs exposure. Meanwhile, antioxidant enzymes activity was decreased following exposure to PCBs. Foliar application of EBR (100 nM) increased biomass, photosynthetic capacity, chlorophyll contents and alleviated photoinhibition by enhancing Fv/Fm, Phi(PSII) and qP. EBR significantly decreased harmful ROS accumulation and lipid peroxidation through the induction of antioxidant enzymes activity. Our results suggest a protective role of EBR against PCBs stress which may strengthen phytoremediation approaches by enhancing plant tolerance. (c) 2012 Elsevier Ltd. All rights reserved.