硒胁迫对钝顶螺旋藻抗氧化酶系统的影响  

EFFECTS OF SELENIUM STRESS ON ANTIOXIDASE SYSTEM OF SPIRULINA PLATENSIS

作　　者：陈思嘉[1] 杨芳[1] 郑文杰[1] 白燕[1] 黄峙[2] 周艳晖[1] 

机构地区：[1]暨南大学化学系,广州510632 [2]暨南大学生物系,广州510632

出　　处：《水生生物学报》2007年第5期706-711,共6页Acta Hydrobiologica Sinica

基　　金：广东省自然科学基金重点项目(05103295);教育部重点项目(01141);广州市科技计划项目(2001-J-010-01)资助

摘　　要：在钝顶螺旋藻的对数生长期进行硒胁迫处理,研究硒胁迫强度和硒胁迫时间对钝顶螺旋藻抗氧化酶系统与脂质过氧化作用的影响。设置4个胁迫实验组,分别从第5天到第10天分次加硒,累计加硒量均为1000 mg/L。结果表明,硒胁迫实验组中钝顶螺旋藻的抗氧化酶活性均高于对照组或与对照组相当,其中GPX的变化最大,实验组Ⅰ中的GPX活性为对照组的20.5倍;SOD的变化趋势与GPX相近,但对较低的硒胁迫的响应不敏感;POD、CAT和APX的活性均随硒胁迫强度的减小而上升;各硒胁迫实验组中只有实验组Ⅰ的MDA含量高于对照组;藻体对.OH的清除能力与藻体的MDA含量呈负相关,提示了硒对钝顶螺旋藻抗氧化系统的双重效应。Selenium （Se） is an essential element for antioxidation reactions in human and animals. It acted as an antioxidant at low concentrations, but as a pro - oxidant at higher ones, consequently it exerted dual effects on organisms. Previous works have shown that Spirulina platensis （ S. platensis） possesses a good tolerance to high levels of Se and it is a good carrier for Se biotransformation. However, there is less information on Se - induced oxidative stress and antioxidant systems in S. platensis. In this paper, we investigated the effects of Se stress on the antioxidase system and lipid peroxidization of S. platensis. There were five test sets in the experiment. Se was added in the logarithm growth time of S. platensis from the 5th to 10thday respectively. The accumulative concentrations of Se in test sets are all 1000 mg/L, but the time of Se addition was different. The results showed that the activities of antioxidase in S. platensis under Se stress were higher than those in the control group or as high as them. GPX changed enormously. The activity of GPX in test set I was 20.5 times as high as control, and then dropped with the decrease of Se stress intensity. The trend of SOD was similar to that of GPX, but its response to Se stress was not sensitive. POD, CAT and APX increased with the drop of Se stress intensity. It was only in the experimental group I that the content of MDA was higher than that in the control group. The ability of S. platensis to scavenge hydroxy radical had a negative correlation with the MDA content. Their changes indicated the dual effects of Se on the antioxidant system of S. platensis. The concept of Se stress intensity can give a good explanation to the experimental results.

关 键 词：硒 钝顶螺旋藻 抗氧化酶 硒胁迫强度 

分 类 号：Q945.11[生物学—植物学]