潮间带生境下两种表型盐地碱蓬的抗氧化系统比较

Comparison on Antioxidant Systems of Two Phenotypes Suaeda salsa L.Grown in Intertidal Zone

比较自然条件下的潮间带生境中紫红色表型和绿色表型盐地碱蓬的抗氧化酶活性和两种表型的过氧化氢含量,并以外源过氧化氢处理紫红色盐地碱蓬离体叶片,分析外源过氧化氢浓度与叶中甜菜红素含量相关性的结果表明:绿色表型的盐地碱蓬叶中过氧化氢含量极显著高于紫红色表型盐地碱蓬,而二者的抗氧化酶[超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)和过氧化氢酶(CAT)]活性差异不显著。外源过氧化氢的浓度与叶中甜菜红素含量呈显著负相关。这表明,甜菜红素可能作为一种非酶促抗氧化剂参与活性氧水平的调节,从而减少逆境胁迫引起的氧化伤害。

In the present study, the leaves of red-violet phenotype and green phenotype Suaeda salsa grown in the same intertidal zone were used to comparatively study the activity of antioxidative enzymes [superoxide dismutase （SOD）, ascorbate peroxidase （APX） and catalase （CAT）] and the content of H2O2, and to examine the correlation between the exogenous H2O2 concentration and betacyanin content of red-violet phenotype using detached leaves. The results showed that the H2O2 content of green phenotype S. salsa leaves was significantly higher than that of red-violet phenotype leaves, while the activities of antioxidative enzymes （SOD, APX and CAT） of the two phenotypes of S. salsa had no significant differences. Correlative analysis showed that the exogenous H2O2 concentration was significantly negative correlated to betacyanin content of the detached leaves of red-violet phenotype S. salsa. These results suggested that betacyanin possibly played a role as a nonenzymatic antioxidant in regulating the level of reactive oxygen species, sequentially alleviating the oxidative damage caused by oxidative stress.