摘要
为明确水体中常见的钙镁钾离子混合物对重金属离子Cu^(2+)、Zn^(2+)、Cr^(6+)、Cd^(2+)和Fe^(3+)毒性的影响,以明亮发光杆菌T3(Photobacterium phosphoreum T3)为受试生物,进行急性毒性测试并通过生化指标及核心发光基因表达量变化进行机理解析。结果表明:单一重金属离子对明亮发光杆菌T3的毒性大小为Zn^(2+)>Cd^(2+)>Cu^(2+)>Fe^(3+)>Cr^(6+),在添加不同浓度Ca^(2+)-Mg^(2+)-K^(+)混合液后重金属离子的毒性降低,当Ca^(2+)、Mg^(2+)和K^(+)质量浓度分别为13.40、8.00和26.20 mg/L时,联合毒性最弱;重金属离子质量浓度较低(<2.0 mg/L)时,重金属离子与Ca^(2+)-Mg^(2+)-K^(+)混合液之间呈拮抗作用,并出现明显的兴奋刺激效应;随着重金属离子质量浓度的增加,联合作用逐渐转为加和作用;Ca^(2+)-Mg^(2+)-K^(+)混合液的加入使细胞内活性氧质量下降,超氧化物歧化酶活性以及还原型烟酰胺腺嘌呤二核苷酸质量上升,使得菌体抗氧化能力增强,并刺激氧化还原反应来提升能量供应水平,从而降低金属离子的毒性。该研究可为实际水体中混合重金属离子的毒性评估和调控提供数据参考。
In order to determine the effect of common calcium-magnesium-potassium ion mixtures in water on the toxicity of heavy metal ions,such as Cu^(2+),Zn^(2+),Cr^(6+),Cd^(2+)and Fe^(3+),acute toxicity tests are carried out using Photobacterium phosphorium T3 as the tested organism.Mechanistic analysis is performed through biochemical indicators and changes in the expression levels of core luminescent genes.The results indicate that the toxicity of individual heavy metal ions to the bioluminescent bacterium T3 follows the order:Zn^(2+)>Cd^(2+)>Cu^(2+)>Fe^(3+)>Cr^(6+).The toxicity of heavy metal ions decreases after the addition of different concentrations of Ca^(2+)-Mg 2-K^(+)mixed solution,with the weakest combined toxicity observed when the mass concentrations of Ca^(2+),Mg^(2+),and K^(+)are 13.40,8.00,and 26.20 mg/L,respectively.Moreover,when the concentration of heavy metal ions is low(<2.0 mg/L),an antagonistic effect is observed between the heavy metal ions and the Ca^(2+)-Mg^(2+)-K^(+)mixture,accompanied by a significant stimulating effect.As the concentration of heavy metal ions increases,the combined action gradually shifts towards an additive effect.The addition of Ca^(2+)-Mg^(2+)-K^(+)mixed solution leads to a decrease in intracellular reactive oxygen species levels,an increase in superoxide dismutase activity and the content of reduced nicotinamide adenine dinucleotide,enhancing the bacterium’s antioxidant capacity and stimulating redox reactions to improve energy supply levels,thereby reducing the toxicity of metal ions.The study can provide data reference for the toxicity evaluation and regulation of mixed heavy metal ions in actual water bodies.
作者
张瑞雪
王丹
周彦宏
张家欢
李珊珊
徐浩
ZHANG Ruixue;WANG Dan;ZHOU Yanhong;ZHANG Jiahuan;LI Shanshan;XU Hao(School of Energy and Power Engineering,Xi’an Jiaotong University,Xi’an 710049,China)
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2024年第11期185-195,共11页
Journal of Xi'an Jiaotong University
基金
国家重点研发计划资助项目(2019YFB2103003)。
