外源抗坏血酸对镉胁迫下黑藻抗氧化系统的保护作用  

Protective effects of exogenous ascorbic acid on antioxidant system in Hydrilla verticillata under Cd^(2+) stress.

作　　者：许丙军[1] 施国新[1] 徐勤松[1] 王学[1] 赵娟[1] 胡金朝[1] 

机构地区：[1]南京师范大学生命科学学院,南京210097

出　　处：《应用生态学报》2006年第9期1768-1770,共3页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(30370083);江苏省教育厅自然科学基金项目(03KJBI800620);江苏省重点实验室开放基金资助项目(164070300805).

摘　　要：研究了不同浓度抗坏血酸(ascorbicacid,AsA)对5mg.L-1Cd2+胁迫下黑藻(Hydrillaverticillata)体内超氧阴离子(O2.-)产生速率、过氧化氢(H2O2)含量、抗坏血酸和谷胱甘肽(GSH)含量,以及超氧化物歧化酶(SOD)、超氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性的影响.结果表明,与单一Cd2+胁迫相比,随着外源AsA浓度的升高,黑藻体内活性氧生成速率逐步降低;抗氧化物质AsA先升后降,GSH缓慢升高;抗氧化酶APX和CAT活性先升后降,POD活性逐步下降,并接近正常状态,对SOD活性影响不大.可见AsA能够有效缓解Cd2+对黑藻的毒害,且60mg.L-1浓度下的缓解效果最好.In this paper, HydriUa verticiUata was cultured in the hoagland solution containing 5 mg · L^-1 Cd^2＋ and different concentration ascorbic acid （AsA） to investigate the protective action of AsA to aquatic plant suffered from heavy metal＇s stress. The O2^- generation rate, H2O2 content, antioxidants （AsA and GSH） contents, and antioxidant enzymes （SOD, POD, CAT and APX） activities were analyzed. The results showed that compared with single Cd^2＋ treatment, AsA addition lessened the reactive oxygen species （O2^- and H2O2 ） generation rates, endogenous AsA content, and antioxidant enzyme activities. It was concluded that exogenous AsA could relieve the Cd^2 ＋ poison to H. verticiUata, and its optimum concentration was 60 mg· L^-1.

关 键 词：抗坏血酸 CD^2+ 黑藻 抗氧化酶 

分 类 号：X173[环境科学与工程—环境科学]