PMID- 23837346
OWN - NLM
STAT- MEDLINE
DCOM- 20130801
LR  - 20191210
IS  - 0959-3330 (Print)
IS  - 0959-3330 (Linking)
VI  - 34
IP  - 5-8
DP  - 2013 Mar-Apr
TI  - Long-term starvation and subsequent recovery of nitrifiers in aerated submerged 
      fixed-bed biofilm reactors.
PG  - 945-59
AB  - The effectiveness of three operational strategies for maintaining nitrifiers in 
      bench-scale, aerated, submerged fixed-bed biofilm reactors (SFBBRs) during 
      long-term starvation at 20 degrees C were evaluated. The operational strategies 
      were characterized by the resulting oxidation-reduction potential (ORP) in the 
      SFBBRs. The activity rates of the nitrifiers were measured and the activity decay 
      was expressed by half-life times. It was found that anoxic and alternating 
      anoxic/aerobic conditions were the best ways to preserve ammonia-oxidizing 
      bacteria (AOB) during long starvation periods and resulted in half-life times of 
      up to 34 and 28 days, respectively. Extended anaerobic conditions caused the 
      half-life for AOB to decrease to 21 days. In comparison, the activity decay of 
      nitrite-oxidizing bacteria (NOB) tended to be slightly faster. The activity of 
      AOB biofilms that were kept for 97 days under anoxic conditions could be 
      completely recovered in less than one week, while over 4 weeks was needed for AOB 
      kept under anaerobic conditions. NOB were more sensitive to starvation and 
      required longer recovery periods than AOB. For complete recovery, NOB needed 
      approximately 7 weeks, regardless of the starvation conditions applied. Using the 
      fluorescence in situ hybridization (FISH) technique, Nitrospira was detected as 
      the dominant NOB genus. Among the AOB, the terminal restriction fragment length 
      polymorphism (TRFLP) technique showed that during starvation and recovery 
      periods, the relative frequency of species shifted to Nitrosomonas 
      europaea/eutropha, regardless of the starvation condition. The consequences of 
      these findings for the operation of SFBBRs under low-load and starvation 
      conditions are discussed.
FAU - Elawwad, Abdelsalam
AU  - Elawwad A
AD  - Department of Environmental Engineering (UST), Otto-von-Guericke 
      University-Magdeburg, c/o Martin Luther University Halle-Wittenberg, Merseburg, 
      Germany. abdelsalam.elawwad@iw.uni-halle.de
FAU - Sandner, Hendrik
AU  - Sandner H
FAU - Kappelmeyer, Uwe
AU  - Kappelmeyer U
FAU - Koeser, Heinz
AU  - Koeser H
LA  - eng
PT  - Comparative Study
PT  - Evaluation Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Environ Technol
JT  - Environmental technology
JID - 9884939
RN  - N762921K75 (Nitrogen)
RN  - S88TT14065 (Oxygen)
SB  - IM
MH  - Air
MH  - Batch Cell Culture Techniques/*instrumentation/methods
MH  - Biofilms
MH  - Bioreactors/*microbiology
MH  - Equipment Design
MH  - Equipment Failure Analysis
MH  - Nitrification
MH  - Nitrogen/*metabolism
MH  - Oxygen/*metabolism
MH  - Oxygen Consumption/*physiology
EDAT- 2013/07/11 06:00
MHDA- 2013/08/02 06:00
CRDT- 2013/07/11 06:00
PHST- 2013/07/11 06:00 [entrez]
PHST- 2013/07/11 06:00 [pubmed]
PHST- 2013/08/02 06:00 [medline]
AID - 10.1080/09593330.2012.722758 [doi]
PST - ppublish
SO  - Environ Technol. 2013 Mar-Apr;34(5-8):945-59. doi: 10.1080/09593330.2012.722758.