Related Experiment Video
Updated: May 26, 2026

A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
[Screening and identification of two heterotrophic nitrifying bacteria and characterization of their capacity for
Dan Pan1, Qiaoyun Huang, Wenli Chen
1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China. pandan126@163.com
Objective:
Two heterotrophic nitrifying bacteria, P2 and P9 isolated from piggery wastewater, were studied for their capacity of nitrification and nitrogen removal.
Methods:
Physiological characteristics and phylogenetic analysis based on 16S rDNA sequences of strains P2 and P9 were analyzed. The ammonia removal characteristics of strains P2 and P9 were investigated. Furthermore, nitrogen removal ability of strains P2 and P9 individually or mixed were evaluated in the treatment of actual piggery wastewater.
Results:
Strains P2 and P9 were identified as Paracoccus sp. and Shinella sp., respectively. Heterotrophic nitrification could occur by the strains when they utilized organics. After cultivation of 24 h, the ammonia removal rates by the strains were up to 80% approximately; meanwhile, there was almost no nitrite and nitrate accumulation. However, aerobic denitrification could not occur by the strains when NO3- or NO2- was provided as the sole nitrogen source, respectively. For heterotrophic nitrification, with strains P2 and P9, the optimal carbon source was sodium succinate, and the optimal C/N ratio was 9. Besides, the pH values rose from 6.8 to 8.9 in the whole ammonia removal process. The growth and nitrogen removal ability of the two strains depended much on the quantity of small molecule carbon source, and the nitrogen removal capability of strains P2 or P9 in wastewater with small molecule carbon source was improved evidently. The effect was strengthened especially when the two strains were mixed together.
Conclusion:
Nitrogen removal ability of strains P2 and P9 was relatively strong, and they may exhibit broad application prospects in wastewater treatment.
More Related Videos
Related Concept Videos
Inorganic Nitrogen Assimilation
Metabolism of Chemolithotrophs
Environmental Applications of Microorganisms
Overview of Nitrogen Metabolism
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this nitrogen...
The Nitrogen Cycle

