摘要
采用室内培养试验方法,以米氏凯伦藻(Karenia mikimotoi)为生物材料,设置不同浓度梯度的重金属Zn^(2+)(0、1、5、10、15和20mg·L^(-1)),主要测定藻细胞密度、光合色素、光合效率、抗氧化酶类、丙二醛(malondialdehyde,MDA)等相关指标,探讨重金属Zn^(2+)胁迫下米氏凯伦藻(Karenia mikimotoi)的生长和生理特征。结果发现,在1和5 mg·L^(-1)的Zn^(2+)浓度下,米氏凯伦藻细胞依然保持较好生长繁殖,表明其具有一定的耐受性,而随着重金属Zn^(2+)浓度的提高,细胞生长受到毒害抑制。光合色素含量呈现动态变化,试验结束时(96 h)叶绿素a、叶绿素b和胡萝卜素含量有各自不同的变化趋势,最大光能转化效率(Fv/Fm)表现出先升后降的趋势。Zn^(2+)浓度为10mg·L^(-1)时,超氧化物歧化酶(superoxidedismutase,SOD)活性显著高于对照;过氧化氢酶(catalase,CAT)活性呈现出先上升后下降的趋势,且5、10、15和20mg·L^(-1)Zn^(2+)浓度下米氏凯伦藻的过氧化氢酶(CAT)活性均显著高于对照;10、15mg·L^(-1)Zn^(2+)浓度下米氏凯伦藻的总抗氧化能力(total antioxidantcapacity,T-AOC)显著高于对照,而20mg·L^(-1) Zn^(2+)浓度下的显著低于对照。丙二醛(MDA)呈现出随着Zn^(2+)浓度提高而增加的趋势,5、10、15和20mg·L^(-1)Zn^(2+)浓度下米氏凯伦藻的丙二醛(MDA)均显著高于对照。结果可为了解重金属对海洋微藻的毒性作用提供数据参考。
An indoor experiment with different concentration gradients of heavy metal Zn^2+(0,1,5,10,15 and 20 mg·L^-1)was carried out by using Karenia mikimotoi as material,and determining the cell density,photosynthetic pigments,photosynthetic efficiency,antioxidant enzymes and malondialdehyde(MDA)to study the growth and physiological characteristics of K.mikimotoi in response to Zn^2+stress.The results showed that under the concentration of 1 and 5 mg·L^-1 Zn^2+,K.mikimotoi cells still maintained good growth and reproduction,indicating that they were tolerant to Zn^2+,meanwhile the growth of cells was inhibited by toxicity with the increase of the Zn^2+concentration.At the end of the experiment(96 h),the contents of chlorophyll a,chlorophyll b and carotene fluctuated,and the maximal photochemical efficiency(Fv/Fm)showed a trend of first rising and then decreasing.The activity of superoxide dismutase(SOD)was significantly higher when the Zn^2+concentration was 10 mg·L^-1 than that of the control;the activity of catalase(CAT)increased first and then decreased,and its activity was significantly higher than that of the control under the Zn^2+concentration of 5,10,15 and 20 mg·L^-1;the total antioxidant capacity(T-AOC)of K.mikimotoi at the Zn^2+concentration of 10 and 15 mg·L^-1 was significantly higher than that of the control,while at the Zn^2+concentration of 20 mg·L^-1 was significantly lower than that of the control.The content of malondialdehyde(MDA)increased with the increase of the Zn^2+concentration,and the content of malondialdehyde(MDA)of K.mikimotoi treated with 5,10,15 and 20 mg·L^-1 Zn^2+concentrations was significantly higher than that in the control.The results can provide data for understanding the toxicity of heavy metals to marine microalgae.
作者
蔡卓平
刘伟杰
段舜山
CAI Zhuoping;LIU Weijie;DUAN Shunshan(Ecological Society of Guangdong Province,Guangzhou 510650,China;Jinan University,Guangzhou 510632,China)
出处
《生态科学》
CSCD
2019年第2期176-181,共6页
Ecological Science
基金
广州市科技计划项目(201707010481)
关键词
重金属
米氏凯伦藻
生长生理
抗氧化酶类
heavy metal
Karenia mikimotoi
growth and physiology
antioxidant enzymes
