| Title: | Distribution and rate of microbial processes in an ammonia-loaded air filter biofilm |
| Author(s): | Juhler S; Revsbech NP; Schramm A; Herrmann M; Ottosen LD; Nielsen LP; |
| Address: | "Department of Biological Sciences, Aarhus University, Denmark. susanne.juhler@biology.au.dk" |
| ISSN/ISBN: | 1098-5336 (Electronic) 0099-2240 (Print) 0099-2240 (Linking) |
| Abstract: | "The in situ activity and distribution of heterotrophic and nitrifying bacteria and their potential interactions were investigated in a full-scale, two-section, trickling filter designed for biological degradation of volatile organics and NH(3) in ventilation air from pig farms. The filter biofilm was investigated by microsensor analysis, fluorescence in situ hybridization, quantitative PCR, and batch incubation activity measurements. In situ aerobic activity showed a significant decrease through the filter, while the distribution of ammonia-oxidizing bacteria (AOB) was highly skewed toward the filter outlet. Nitrite oxidation was not detected during most of the experimental period, and the AOB activity therefore resulted in NO(2)(-), accumulation, with concentrations often exceeding 100 mM at the filter inlet. The restriction of AOB to the outlet section of the filter was explained by both competition with heterotrophic bacteria for O(2) and inhibition by the protonated form of NO(2)(-), HNO(2). Product inhibition of AOB growth could explain why this type of filter tends to emit air with a rather constant NH(3) concentration irrespective of variations in inlet concentration and airflow" |
| Keywords: | *Air Ammonia/*metabolism Animals Bacteria/*isolation & purification/*metabolism Biofilms/*growth & development *Filtration In Situ Hybridization Nitrites/metabolism Oxidation-Reduction Polymerase Chain Reaction Reactive Nitrogen Species/metabolism Swine V; |
| Notes: | "MedlineJuhler, Susanne Revsbech, Niels Peter Schramm, Andreas Herrmann, Martina Ottosen, Lars D M Nielsen, Lars Peter eng Research Support, Non-U.S. Gov't 2009/04/14 Appl Environ Microbiol. 2009 Jun; 75(11):3705-13. doi: 10.1128/AEM.02612-08. Epub 2009 Apr 10" |
