Response of antioxidant activity to excess copper in two cultivars of Brassica campestris ssp chinensis Makino
Response of antioxidant activity to excess copper in two cultivars of Brassica campestris ssp chinensis Makino
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两个油菜品种的抗氧化活性对过量铜的响应。
DOI：
10.1007/s11738-008-0216-9
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发表时间：
2009-01-01
影响因子：
2.6
通讯作者：
Hou, Xilin
中科院分区：
文献类型：
--
作者：
Li, Ying;Song, Yuping;Hou, Xilin
以不结球白菜为试材，研究了其抗坏血酸含量和抗氧化酶活性的变化。结果表明，在过量铜胁迫下，乌塔菜和二青叶片中Cu含量明显升高。铜处理使乌塔菜地上部和地下部鲜重分别下降57%和46%，使二青地上部鲜重下降60%和54%。‘乌塔菜’叶片中铜的积累量高于‘二青’。与对照相比，铜处理后两个品种抗坏血酸（阿萨）含量均显著降低，但“乌塔菜”抗坏血酸含量高于“二青”，这可能解释了“乌塔菜”耐铜性强、铜积累量高的原因。“乌塔菜”阿萨含量高于“二青”是由于铜处理后其抗坏血酸氧化酶（AAO）和抗坏血酸过氧化物酶（APX）等降解酶活性降低，脱氢抗坏血酸还原酶（达尔）活性升高所致。铜刺激超氧化物歧化酶（SOD）的活性在两个品种，但过氧化氢酶（CAT），两个品种之间的差异不大。铜处理后，二青的过氧化物酶（POD）活性降低，而乌塔菜在14 d时POD活性显著升高，且21和28 d时乌塔菜的POD活性高于二青。因此，‘乌塔菜’POD活性的诱导提高在其耐铜性中也起着重要作用。
Changes in ascorbic acid content and antioxidant enzyme activities were investigated in non-heading Chinese cabbage (Brassica campestris ssp. chinensis Makino) leaves of 'Wutacai' and 'Erqing' exposed to excess copper (Cu). Cu treatment reduced the fresh weight of shoot and root by 57% and 46% in 'Wutacai', and 60 and 54% in 'Erqing', respectively. The accumulation of copper in leaves was higher in 'Wutacai' than that in 'Erqing'. Compared to the control, ascorbic acid (AsA) contents were significantly decreased after copper treatment in both cultivars, while they were higher in 'Wutacai' than in 'Erqing', which may explain the higher copper-tolerance of 'Wutacai' with higher copper accumulation. The higher AsA contents of 'Wutacai' resulted from their lower activities of degrading enzymes, such as ascorbate oxydase (AAO) and ascorbate peroxidase (APX), as well as the increasing activity of dehydroascorbate reductase (DHAR) after copper treatment compared with 'Erqing'. Copper stimulated superoxide dismutase (SOD) activity in both cultivars, but for catalase (CAT), there was little difference between both cultivars. Peroxidases (POD) activity was decreased after copper treatment in 'Erqing', while in 'Wutacai', it was significantly increased at 14 days, and POD activity was higher in 'Wutacai' than that in 'Erqing' at 21 and 28 days. Therefore, the induced increasing activity of POD in 'Wutacai' also played an important role in its copper tolerance.