Ni2+、Cu2+、Zn2+对氧化亚铁硫杆菌氧化 活性影响

为研究金属离子对氧化亚铁硫杆菌（Acidithiobacillus ferrooxidans，At.f）氧化活性的影响，通过测定经初步驯化的At.f菌在不同初始pH下的生长活性，开展不同浓度梯度的Ni2+、Cu2+、Zn2+及三种金属离子共存时对At.f菌的氧化活性影响的试验。结果表明，当初始pH为1.8时，At.f菌生长活性最好，且低浓度的Ni2+、Zn2+对At.f菌氧化活性影响较小，对两种金属离子的耐受浓度均在20 g/L以上；而该细菌对Cu2+比较敏感，当Cu2+浓度为2.5 g/L时，菌株的生长活性明显下降，特别是10 g/L时，对At.f菌的氧化能力有显著的抑制作用。三种金属离子同时存在时对At.f菌氧化活性的影响大于单一金属离子，当三种金属离子的浓度均为2.5 g/L时，在48小时内对At.f菌的氧化能力有显著的抑制作用，当三种金属离子的浓度均为5 g/L时，80小时时菌株对Fe2+的氧化率极低，说明At.f菌需要经过多种金属离子共存驯化培养后才能更好地运用于多金属复杂矿物的处理。

Effect of Ni2+, Cu2+, and Zn2+ on Oxidation Activity of Acidithiobacillus Ferrooxidans

In order to study the effect of metal ions on oxidation activity of Acidithiobacillus ferrooxidans(At.f), effects of Ni2+, Cu2+, Zn2+ and three metal ions coexisting in different concentration gradients on oxidation activity of At.f were investigated by measuring the growth activity of domestication At.f under different condition of initial pH value. The result show that the growth activity of At.f is the best when the initial pH value is 1.8, low concentration of Ni2+ and Zn2+ has little effect on oxidation activity of At.f, and its tolerance concentration of Ni2+ and Zn2+ is above 20 g/L. The bacterium is sensitive to Cu2+, when concentration of Cu2+ is 2.5 g/L, the growth activity of strain drops significantly, especially at 10 g/L, the oxidation ability of At.f is significantly inhibited. When three metal ions exist simultaneously, the effect of At.f on oxidation activity of bacteria is greater than that of single metal ions. When concentration of all three metal ions is 2.5 g/L, the oxidation ability of At.f is significantly inhibited with 48 hours. When concentration of all three metal ions is 5 g/L, the oxidation rate of Fe2+ was very low at 80 h, it is suggested that At.f bacteria can be better used in treatment of complex polymetallic complex minerals after domestication and culture with coexistence of multiple metal ions.