College of Environmental Science and Engineering, Guilin University of Technology, Yanshan, Guilin 541006, China.
Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Yanshan, Guilin 541006, China.
Int J Environ Res Public Health. 2022 Sep 2;19(17):10974. doi: 10.3390/ijerph191710974.
As algae are extremely sensitive to heavy-metal ions and can be critical biological indicators in the heavy-metal toxicity analyses conducted by environmental health researchers, this paper explores the sensitivity to temporal toxicity of three species of green algae: , , and . The method of time-dependent microplate toxicity analysis was used to systematically investigate the changes in the toxicities of the three green-algae species induced by different concentrations of cadmium (Cd). The chlorophyll content, antioxidant enzyme activity, and malondialdehyde (MDA) content in the algae were analyzed to explore the mechanism of Cd toxicity after 96 h of exposure. The results showed that the toxic effects of Cd on the three algae species were time-dependent. By comparing the toxic effect of Cd, indicated by pEC (the negative logarithm of EC), on the algae species at four durations of exposure (24, 48, 72, and 96 h), this study found that the indicator organisms had different sensitivities to Cd. The order of sensitivity was > > . Cd exposure had significant effects on the chlorophyll and MDA content and on the enzyme activity of superoxide dismutase (SOD) and catalase (CAT) in the algae species. The chlorophyll content in the cells of the algae decreased with increasing Cd concentration. The enzyme activity of CAT and content of MDA increased with increasing Cd concentration, which indicated that Cd had an oxidative stress effect on the three algae species.
由于藻类对重金属离子极为敏感，并且可以作为环境健康研究人员进行重金属毒性分析的关键生物指标，因此本文探讨了三种绿藻： 、 和 对时间毒性的敏感性。采用时间依赖性微孔板毒性分析方法，系统研究了不同浓度镉（Cd）对三种绿藻物种毒性的变化。分析了藻类中的叶绿素含量、抗氧化酶活性和丙二醛（MDA）含量，以探讨暴露 96 h 后 Cd 毒性的机制。结果表明，Cd 对三种藻类的毒性作用具有时间依赖性。通过比较 Cd 对四种暴露时间（24、48、72 和 96 h）的藻类物种的毒性效应（由 pEC 表示，EC 的负对数），本研究发现指示生物对 Cd 的敏感性不同。敏感性顺序为 > > 。Cd 暴露对藻类物种的叶绿素含量和 MDA 含量以及超氧化物歧化酶（SOD）和过氧化氢酶（CAT）的酶活性有显著影响。藻类细胞中的叶绿素含量随 Cd 浓度的增加而降低。CAT 酶活性和 MDA 含量随 Cd 浓度的增加而增加，表明 Cd 对三种藻类物种具有氧化应激作用。
