高效氨氮降解菌的筛选及降解效率测定

The Screening of the Ammonia Nitrogen Degrading Bacteria and Measurement of Degradation Efficiency

本研究为获得高效降解氨氮废水的菌株资源,采用平板分离和划线纯化的技术从高氨氮废水中富集分离出了6株具有氨氮降解能力的菌株,并将它们接种到氨氮含量较高的鸡粪废水中,培养48 h后,每隔8 h测定一次氨氮浓度,使用纳氏试剂法检测氨氮浓度,筛选出了一株最佳的氨氮降解菌株。结果表明,在初始氨氮浓度为3.19 mg/mL的鸡粪废水中,本研究分离的6株菌株都能有效地降低废水中的氨氮浓度,其降解过程符合Boltzmann模型曲线,菌株N-1~N-6处理48 h后,废水中的氨氮浓度分别降低到2.48、2.47、2.49、2.55、2.37、2.53 mg/mL,平均降解效率分别为14.79、15.21、14.38、13.33、17.08、13.54 mg/(L·h),其中菌株N-5的降解效率最高,通过16S rDNA基因测序确定该菌与灰锈赤链霉菌Streptomyces griseorubiginosus相似度为99.13%,故命名为Streptomyces griseorubiginosus N-5。本研究获得的菌株N-5具有耐受高浓度氨氮和强降解能力的特点,在处理养殖废水方面具有较大的应用前景。

This research aims to obtain bacterial that can effectively degrade wastewater containing ammonia nitrogen.6 strains with degrading ammonia nitrogen ability were enriched and isolated from high ammonia nitrogen wastewater using plate isolation and streak purification techniques.These strains were subsequently inoculated into chicken manure wastewater with high ammonia nitrogen content.After 48 hours of cultivation,the ammonia nitrogen concentration was measured every 8 hours using the Nessler's reagent method to select the best ammonia nitrogen degradation strain.It’s showed that all the 6 strains could effectively reduce the ammonia nitrogen concentration in wastewater with an initial concentration of 3.19 mg/mL.The degradation process followed the Boltzmann curve model.After 48 hours treatment by strain N-1 to N-6,the ammonia nitrogen concentrations decreased to 2.48 mg/mL,2.47 mg/mL,2.49 mg/mL,2.55 mg/mL,2.37 mg/mL and 2.53 mg/mL,respectively.The average degradation efficiency was 14.79,15.21,14.38,13.33,17.08 and 13.54 mg/(L·h),indicating that the strain N-5 exhibited the highest degradation efficiency.Moreover,it had 99.13%similarity to strain Streptomyces griseorubiginosus by the method of 16S rDNA gene sequencing,so it was named Streptomyces griseorubiginosus N-5.The strain N-5 obtained in this study possessed the characteristics of high tolerance to high concentrations of ammonia nitrogen and strong degradation capability.It holds great application prospects for treating livestock wastewater.