金属纳米材料在厌氧条件下对脱氮副球菌反硝化作用的影响

以脱氮副球菌YF1为实验菌株,研究纳米Fe0和纳米Fe/Ni 2种金属纳米材料对菌体生长及其反硝化作用的影响。实验结果表明:添加纳米材料到反应体系中会降低实验菌株的生长量和生物反硝化作用,纳米Fe/Ni对实验菌株的毒性比纳米Fe0大。在含硝态氮初始浓度为100 mg/L的反硝化培养基中接种脱氮副球菌,于30℃培养20 h,脱氮率为89.47%,而菌+1 000 mg/L纳米Fe/Ni的体系脱氮率仅为64.33%;菌+1 000 mg/L纳米Fe0体系的脱氮率为76.36%。不同体系的反硝化过程均可采用零级动力学模型进行拟合(相关系数R2>0.92)。这2种金属纳米材料对实验菌株的生长量及其反硝化作用的影响程度,与体系的pH和温度有较大关系。

Effect of metallic nanoparticles on denitrification by Paracoccus sp. under anaerobic conditions

The present study explored the effect of Fe and Fe/Ni nanoparticles on the cell growth and the denitrification using Paracoccus sp. YF1 as the experiment strain.The results showed that addition of the nanoparticles to bacteria systems inhibited the growth and the biological denitrification,where the toxicity of Fe/Ni nanoparticles was higher than that of Fe nanoparticles.Paracoccus sp. YF1 was inoculated in solution containing 100 mg/L nitrate medium at 30℃ for 20 h with a denitrification of 89.47%,while the 64.33% biological denitrification and ceased completely denitrification were observed at concentration of 1 000 mg/L Fe/Ni nanoparticles.However,the removal rate of nitrate in the Fe0+cell system was 76.36%.Different systems were fitting by zero order dynamical model(R2>0.92) and the solution pH and the temperature could impact the metallic nanoparticles on the growth and the denitrification.