污染水体中氨氮降解菌的筛选与降解特性研究

为研究污染水体中微生物对氨氮的降解能力,寻求安全有效的治理技术,从浙江安吉南北湖的底泥中分离筛选出12株具有氨氮降解能力的菌株X1至X12,以(NH4)2SO4为唯一氮源,对比12株菌株的生长情况与氨氮降解率,挑选出脱氮能力较强的菌株X1和X2。活化后的菌株X1和X2反应48h,氨氮降解率分别为98.05%、97.63%,且反应体系的亚硝酸盐氮和硝酸盐氮积累均极少。未经活化的菌株X1和X2反应48h,氨氮降解率分别为96.40%、97.90%,也未出现明显的硝酸盐氮和亚硝酸盐氮积累。通过观察形态特征、测定生化性质和比对16SrDNA序列,鉴定出菌株X1为浅黄色假单胞菌(Pseudomonas lurida),菌株X2为Pseudomonas weihenstephanensis。菌株X1和X2生长速率快,易成为优势菌种,降解氨氮能力显著,在污染水体生物修复领域具有良好的应用前景。

Screening of ammonia nitrogen degradation strains and their degrading characteristics from contaminated water

The research was aimed to study the microbiological degradation ability for ammonia nitrogen,providing the more safe and effective control measures for solving the problem of water pollution. Using (NH4)2SO4 as the sole nitrogen source medium,12 ammonia nitrogen degrading bacterial strains X1-X12 were isolated from the sediments of Anji Nanbei Lake in Zhejiang,and then strains X1 and X2 with the maximal degrading rate were screened from the isolated bacterial strains by detecting the growth and ammonia nitrogen degrading ability. The ammonia nitrogen degradation rate of activated strains X1 and X2 were 98.05% and 97.63% within 48 h,respectively. The ammonia nitrogen degradation rate of non- activated strains X1 and X2 were 96.40% and 97.90% within 48 h,respectively. Activated and non-activated strains X1 and X2 both showed minimal nitrite nitrogen and nitrate nitrogen accumulation. Strains X1 and X2 were respectively identified as Pseudomonas lurida and Pseudomonas weihenstephanensis by morphological,biochemical tests and16S rDNA sequence analysis. Because of their fast growth rate,strains X1 and X2 were easy to be the dominant strains with significant ammonia nitrogen degrading ability,they had good application prospect in the bioremediation of water pollution.