PMID- 18541284
OWN - NLM
STAT- MEDLINE
DCOM- 20081031
LR  - 20080625
IS  - 0043-1354 (Print)
IS  - 0043-1354 (Linking)
VI  - 42
IP  - 13
DP  - 2008 Jul
TI  - Microbial population dynamics during aerobic sludge granulation at different 
      organic loading rates.
PG  - 3552-60
LID - 10.1016/j.watres.2008.05.005 [doi]
AB  - Laboratory experiments were carried out to investigate the evolution of the 
      bacterial community during aerobic sludge granulation. The experiments were 
      conducted in three 2.4L sequencing batch reactors (SBRs) that were seeded with 
      activated sludge and fed with glucose-based synthetic wastewater. Three different 
      influent organic concentrations were introduced into the three SBRs, R1, R2 and 
      R3, resulting in chemical oxygen demand (COD) loading rates of 1.5 (R1), 3.0 (R2) 
      and 4.5 (R3)kg/m(3)d, respectively. Changes in bacterial diversity throughout the 
      granulation process were monitored and analysed using polymerase chain reaction 
      (PCR) and denaturing gradient gel electrophoresis (DGGE) techniques. The 
      experimental results demonstrate that glucose-fed aerobic granules could be 
      formed without significant presence of filamentous bacteria. Granules formed at 
      different loading rates had different morphology, structural properties and 
      bacterial species. A higher loading rate resulted in faster formation of larger 
      and loose granules, while a lower loading rate resulted in slower formation of 
      smaller and more tightly packed granules. The biomass underwent a dynamic 
      transformation in terms of bacterial species richness and dominance during the 
      granulation process. The reactor with the highest substrate loading rate had the 
      lowest species diversity, while the reactor with the lowest substrate loading 
      rate had the highest species diversity. Different dominant species of beta- and 
      gamma-Proteobacteria and Flavobacterium within the granule communities from the 
      three different SBRs were confirmed by analysis of 16S rDNA sequences of the PCR 
      products separated by DGGE. It is apparent that a few common bacterial species 
      play an important role in the formation and growth of aerobic granules and help 
      sustain the granular sludge structure in the bioreactors.
FAU - Li, An-jie
AU  - Li AJ
AD  - Department of Civil Engineering, Environmental Engineering Research Centre, The 
      University of Hong Kong, Pokfulam Road, Hong Kong, China.
FAU - Yang, Shu-fang
AU  - Yang SF
FAU - Li, Xiao-yan
AU  - Li XY
FAU - Gu, Ji-dong
AU  - Gu JD
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20080517
PL  - England
TA  - Water Res
JT  - Water research
JID - 0105072
RN  - 0 (Sewage)
SB  - IM
MH  - Aerobiosis
MH  - Microscopy, Electron, Scanning
MH  - Sewage/*microbiology
EDAT- 2008/06/11 09:00
MHDA- 2008/11/01 09:00
CRDT- 2008/06/11 09:00
PHST- 2007/12/12 00:00 [received]
PHST- 2008/04/19 00:00 [revised]
PHST- 2008/05/07 00:00 [accepted]
PHST- 2008/06/11 09:00 [pubmed]
PHST- 2008/11/01 09:00 [medline]
PHST- 2008/06/11 09:00 [entrez]
AID - S0043-1354(08)00206-6 [pii]
AID - 10.1016/j.watres.2008.05.005 [doi]
PST - ppublish
SO  - Water Res. 2008 Jul;42(13):3552-60. doi: 10.1016/j.watres.2008.05.005. Epub 2008 
      May 17.