H2S degradation is reflected by both the activity and composition of the microbial community in a compost biofilter.
In this study, 16S rRNA- and rDNA-based denaturing gradient gel electrophoresis (DGGE) were used to study the temporal and spatial evolution of the microbial communities in a compost biofilter removing H(2)S and in a control biofilter without H(2)S loading. During the first 81 days of the experiment, the H(2)S removal efficiencies always exceeded 93% at loading rates between 4.1 and 30 g m(-3) h(-1). Afterwards, the H(2)S removal efficiency decreased to values between 44 and 71%. RNA-based DGGE analysis showed that H(2)S loading to the biofilter increased the stability of the active microbial community but decreased the activity-based diversity and evenness. The most intense band in both the RNA- and DNA-based DGGE patterns of the H(2)S-degrading biofilter represented the sulfur oxidizing bacterium Thiobacillus thioparus. This suggested that T. thioparus constituted a major part of the bacterial community and was an important primary degrader in the H(2)S-degrading biofilter. The decreasing H(2)S removal efficiencies near the end of the experiment were not accompanied by a substantial change of the DGGE patterns. Therefore, the decreased H(2)S removal was probably not caused by a failing microbiology but rather by a decrease of the mass transfer of substrates after agglutination of the compost particles.
Environmental Organic Chemistry & Technology Research Group (EnVOC), Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
Bram
B
Sercu
Nico
N
Boon
Willy
W
Verstraete
Herman
H
Van Langenhove
D019149:Bioreactors; D006862:Hydrogen Sulfide / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S; D012987:Soil; D012988:Soil Microbiology; D013855:Thiobacillus / Q000302:isolation & purification; D013997:Time Factors
D012336:RNA, Ribosomal, 16S; D012987:Soil; D006862:Hydrogen Sulfide