离子强度对外源纳米银形态转化和氨氧化细菌Nitrosomonas europaea活性的影响  

Effect of ionic strength on the form transformation of exogenous silver nanoparticles and the activity of ammonia-oxidizing bacteria Nitrosomonas europaea

作　　者：杨宝瑞 黄亚惠 张雯雯 杨新萍 YANG Baorui;HUANG Yahui;ZHANG Wenwen;YANG Xinping(Department of Environmental Science and Engineering,College of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210095,China)

机构地区：[1]南京农业大学资源与环境科学学院环境科学与工程系,南京210095

出　　处：《环境工程学报》2025年第1期144-151,共8页Chinese Journal of Environmental Engineering

基　　金：国家自然科学面上基金资助项目(31870489)。

摘　　要：以氨氧化细菌—欧洲亚硝化单胞杆菌(Nitrosomonas europaea)为模式菌株,研究纳米银(silver nanoparticles,AgNPs)在不同离子强度水样中的赋存形态及对N.europaea氧化NH_(4)^(+)-N性能的影响。在N.europaea培养液、月牙湖水、生活污水、化工废水4种水样中分别添加AgNPs及不同形态Ag化合物,测试其对N.europaea的急性毒性,得到AgNPs及不同形态银对N.europaea的毒性效应浓度EC_(20)、EC_(50)和EC_(80)。采用紫外可见吸收光谱法分析AgNPs在不同离子强度水样中的粒径变化。利用Visual MINTEQ模型预测AgNPs在4种水样中的主要化学形态分布,发现水样的离子组分及离子强度显著影响AgNPs的聚集和Ag的赋存状态。在4种水样中分别添加不同浓度(EC_(20)、EC_(50)和EC_(80))的AgNPs,探究不同离子强度水样中的AgNPs对N.europaea活性的影响,结果表明随着水样中外源添加AgNPs浓度的增加,N.europaea氧化NH_(4)^(+)-N的效率降低,特别在培养液和校园生活污水中,呈现较明显的剂量效应;但在月牙湖水和化工废水中,由于其含有高浓度SO_(4)^(2−)、Cl^(-)等离子组分,影响AgNPs对N.europaea的毒性效应。评价AgNPs在环境水体或污水中的生物毒性,应考虑水中离子组成和离子强度对其毒性的影响。With the ammonia-oxidizing bacterium Nitrosomonas europaea as a model strain,the study investigated the chemical transformation of silver nanoparticles(AgNPs)in water samples with varying ionic strengths and their impact on the ammonia oxidation ability of N.europaea.Initially,AgNPs and various silver compounds were added into the culture medium of N.europaea,as well as water samples from Yueya Lake,domestic sewage,and chemical wastewater,respectively,to assess their acute toxicity towards N.europaea.The toxic effect concentrations,namely EC_(20),EC_(50) and EC_(80) of AgNPs and different forms of silver compounds on N.europaea were determined.The particle size of AgNPs in water samples with different ionic strengths was analyzed using UV-vis absorption spectroscopy.The Visual MINTEQ model was used to predict the distribution of the main chemical forms of AgNPs in four water samples,it was found that the ion composition and ion strength of the water samples significantly affected the distribution of different forms of silver compounds in the water samples.Different concentrations of AgNPs(EC_(20),EC_(50),and EC_(80))were added to four different water samples to investigate the effect of AgNPs on the activity of N.europaea in water samples under different ionic strengths.The results showed that as the concentration of AgNPs added externally to the water samples increased,the efficiency of N.europaea oxidation of NH_(4)^(+)-N decreased,especially in the culture medium and domestic sewage,showing a significant dose effect;However,in the Yueya Lake water and chemical wastewater,due to the high concentration of SO_(4)^(2−)and Cl^(-),the toxic effects of AgNPs on N.europaea were alleviated.To evaluate the biological toxicity of AgNPs in environmental water bodies or sewage,the influence of ion composition and ion strength in water on their toxicity should be considered.

关 键 词：纳米银 欧洲亚硝化单胞杆菌 赋存形态 毒性效应 氨氧化 

分 类 号：X703[环境科学与工程—环境工程]