一株卓贝尔氏菌的分离鉴定及氨氧化特性的优化

Isolation and Identification of a Strain of Zobellella sp.and Optimization of Ammonia Oxidation Characteristics

为了准确阐明卓贝尔氏菌对污染水体中NH4^+-N的氧化效率,以清河底泥为菌源,分离筛选出1株氨氧化能力较强的卓贝尔氏菌(Zobellella sp.)。考察了该菌株在不同培养条件下对NH4^+-N硝化效率的影响,利用响应面分析法对培养条件进行优化。结果表明,该菌株4 d内的氨氧化强度为27.88 mg/(L·d),当COD/ρ(TN)为11、pH为8.5、温度为25℃时,该菌在24 h内将NH4^+-N的质量浓度从171.1 mg/L降至11.88 mg/L,氧化效率高达93.06%;建立二次方程回归模型对实验数据拟合结果良好,优化后的培养条件为COD/ρ(TN)=10.72、pH=8.27、θ=25.72℃,在此条件下该菌的NH4^+-N氧化率为94.82%。可为污染水体中NH4^+-N去除的生物方法提供了理论指导依据。

In order to accurately clarify the removal efficiency of ammonia nitrogen in polluted water by Zobellella sp.bacteria,a strain of Zobellella sp.with strong ammonia nitrogen oxidation ability was isolated and screened,using clear river sediment as the source of bacteria.The effects of culture conditions on the degradation rate of ammonia nitrogen by Zobellella sp.were investigated,and the culture conditions were optimized by response surface analysis.The results showed that when C/N was 11,pH was 8.5 and the temperature was 25,the bacteria reduced the mass concentration of ammonia nitrogen from 171.1 mg/L to 11.88 mg/L,and the degradation rate was up to 93.06%;The two equation regression model was fit the experimental data well.The optimum culture condition was C/N of 10.72,pH of 8.27,θof 25.72℃,and the degradation rate of ammonia nitrogen was 94.82%under this condition,which provides a theoretical basis for biological methods of ammonia nitrogen removal in polluted water.