1
|
Characteristics of Ammonia Removal and Nitrifying Microbial Communities in a Hybrid Biofloc-RAS for Intensive Litopenaeus vannamei Culture: A Pilot-Scale Study. WATER 2020. [DOI: 10.3390/w12113000] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Ammonia is the main pollution factor of the aquatic environment in marine shrimp culture systems. In order to demonstrate the feasibility of the combination of biofloc technology and nitrifying biofilter for the ammonia removal, a 70-day production trial was conducted in a simplified pilot-scale hybrid biofloc-based recirculating aquaculture system (biofloc-RAS) with the intensive culture of Litopenaeus vannamei. Nitrogen dynamics and nitrifying microbial communities were investigated in three replicated systems simultaneously under the conditions of high feed loading and zero water exchange. Along with biofloc development in the culture tank and biofilm formation in the nitrifying biofilter during the trial, nitrification could be fastly and effectively established in the system, which was indicated by the dynamics of total ammonia nitrogen (TAN), NO2–-N, NO3–-N, and total nitrogen (TN) concentrations. Meanwhile, similar nitrifying microorganisms could be found between biofloc and biofilm, despite some differences in abundance, diversity, and composition of ammonia-oxidizing archaea and bacteria and nitrite-oxidizing bacteria. High TAN removal rate could be achieved and was significantly and positively correlated with abundances of these nitrifying microbial communities in both biofloc and biofilm, further indicating that both biofloc and biofilm could contribute highly to nitrification performance of the biofloc-RAS. The results of this study indicate a potential application of the biofloc-RAS in coastal intensive aquaculture.
Collapse
|
2
|
Navada S, Sebastianpillai M, Kolarevic J, Fossmark RO, Tveten AK, Gaumet F, Mikkelsen Ø, Vadstein O. A salty start: Brackish water start-up as a microbial management strategy for nitrifying bioreactors with variable salinity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 739:139934. [PMID: 32534315 DOI: 10.1016/j.scitotenv.2020.139934] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 06/01/2020] [Accepted: 06/01/2020] [Indexed: 06/11/2023]
Abstract
Nitrifying biofilms developed in brackish water are reported to be more robust to salinity changes than freshwater biofilms. This makes them a promising strategy for water treatment systems with variable salinity, such as recirculating aquaculture systems for Atlantic salmon. However, little is known about the time required for nitrification start-up in brackish water or the microbial community dynamics. To investigate the development of nitrifying biofilms at intermediate salinity, we compared the startup of moving bed biofilm reactors with virgin carriers in brackish- (12‰ salinity) and freshwater. After 60 days, the brackish water biofilm had half the nitrification capacity of the freshwater biofilm, with a less diverse microbial community, lower proportion of nitrifiers, and a significantly different nitrifying community composition. Nitrosomonas and Nitrosospira-like bacteria were the main ammonia oxidizers in the brackish water biofilms, whereas Nitrosomonas was dominant in freshwater biofilms. Nitrotoga was the dominant nitrite oxidizer in both treatments. Despite the lower nitrification capacity in the brackish water treatment, the low ammonia and nitrite concentration with rapidly increasing nitrate concentration indicated that complete nitrification was established in both reactors within 60 days. The results suggest that biofilms develop nitrification in brackish water in comparable time as in freshwater, and brackish start-up can be a strategy for bioreactors with varying salinity.
Collapse
Affiliation(s)
- Sharada Navada
- Department of Chemistry, NTNU Norwegian University of Science and Technology, N-7491 Trondheim, Norway; Krüger Kaldnes AS (Veolia Water Technologies), N-3241 Sandefjord, Norway.
| | - Marianna Sebastianpillai
- Department of Biotechnology and Food Science, NTNU Norwegian University of Science and Technology, N-7491 Trondheim, Norway
| | | | - Ragnhild O Fossmark
- Department of Environmental and Civil Engineering, NTNU Norwegian University of Science and Technology, N-7031 Trondheim, Norway
| | - Ann-Kristin Tveten
- Department of Biological Sciences, NTNU Norwegian University of Science and Technology, N-6009 Ålesund, Norway
| | - Frédéric Gaumet
- Krüger Kaldnes AS (Veolia Water Technologies), N-3241 Sandefjord, Norway
| | - Øyvind Mikkelsen
- Department of Chemistry, NTNU Norwegian University of Science and Technology, N-7491 Trondheim, Norway
| | - Olav Vadstein
- Department of Biotechnology and Food Science, NTNU Norwegian University of Science and Technology, N-7491 Trondheim, Norway
| |
Collapse
|
3
|
Yasuda S, Toyoda R, Agrawal S, Suenaga T, Riya S, Hori T, Lackner S, Hosomi M, Terada A. Exploration and enrichment of methane-oxidizing bacteria derived from a rice paddy field emitting highly concentrated methane. J Biosci Bioeng 2020; 130:311-318. [PMID: 32487498 DOI: 10.1016/j.jbiosc.2020.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 04/06/2020] [Accepted: 04/20/2020] [Indexed: 12/11/2022]
Abstract
Methane-oxidizing bacteria (MOB) possess the metabolic potential to assimilate the highly potent greenhouse gas, CH4, and can also synthesize valuable products. Depending on their distinct and fastidious metabolic pathways, MOB are mainly divided into Type I and Type II; the latter are known as producers of polyhydroxyalkanoate (PHA). Despite the metabolic potential of MOB to synthesize PHA, the ecophysiology of MOB, especially under high CH4 flux conditions, is yet to be understood. Therefore, in this study, a rice paddy soil receiving a high CH4 flux from underground was used as an inoculum to enrich MOB using fed-batch operation, then the enriched Type II MOB were characterized. The transitions in the microbial community composition and CH4 oxidation rates were monitored by 16S rRNA gene amplicon sequencing and degree of CH4 consumption. With increasing incubation time, the initially dominant Methylomonas sp., affiliated with Type I MOB, was gradually replaced with Methylocystis sp., Type II MOB, resulting in a maximum CH4 oxidation rate of 1.40 g-CH4/g-biomass/day. The quantification of functional genes encoding methane monooxygenase, pmoA and PHA synthase, phaC, by quantitative PCR revealed concomitant increases in accordance with the Type II MOB enrichment. These increases in the functional genes underscore the significance of Type II MOB to mitigate greenhouse gas emission and produce PHA.
Collapse
Affiliation(s)
- Shohei Yasuda
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan.
| | - Risako Toyoda
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan.
| | - Shelesh Agrawal
- Department of Civil and Environmental Engineering Science, Institute IWAR, Chair of Wastewater Engineering, Technische Universität Darmstadt, Franziska-Braun-Straße 7, 64287 Darmstadt, Germany.
| | - Toshikazu Suenaga
- Global Innovation Research Institute, Tokyo University of Agriculture and Technology, 3-8-1 Harumi-cho, Fuchu, Tokyo 185-8538, Japan.
| | - Shohei Riya
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan.
| | - Tomoyuki Hori
- Environmental Management Research Institute, National Institute of Advanced Industrial Science and Technology, 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan.
| | - Susanne Lackner
- Department of Civil and Environmental Engineering Science, Institute IWAR, Chair of Wastewater Engineering, Technische Universität Darmstadt, Franziska-Braun-Straße 7, 64287 Darmstadt, Germany.
| | - Masaaki Hosomi
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan.
| | - Akihiko Terada
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka, Koganei, Tokyo 184-8588, Japan; Global Innovation Research Institute, Tokyo University of Agriculture and Technology, 3-8-1 Harumi-cho, Fuchu, Tokyo 185-8538, Japan.
| |
Collapse
|
4
|
Sousa MR, Oliveira CJS, Carneiro JM, Lopes AC, Rodríguez E, Vasconcelos EAF, Holanda GBM, Landim PGC, Silva MER, Firmino PIM, Dos Santos AB. Evaluation of different air dosing strategies to enhance H 2S removal in microaerobic systems treating low-strength wastewaters. ENVIRONMENTAL TECHNOLOGY 2019; 40:3724-3734. [PMID: 29888986 DOI: 10.1080/09593330.2018.1487470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 05/30/2018] [Indexed: 06/08/2023]
Abstract
This study aimed to evaluate different air dosing strategies such as microaeration flow rates and air dosing points to enhance H2S removal in microaerobic systems treating low-strength wastewaters. Efficiency and stability of the reactors, as well as biogas quality, were assessed, and microbial community changes were evaluated using the PCR-DGGE technique. The results showed that the air dosing point affected the H2S concentration and that air dosing at the headspace promoted the highest H2S removal efficiency. The airflow rate also affected the process, since H2S concentration in the biogas was higher at 0.1 mL air.min-1 than at 0.3 mL air.min-1. The methane concentration in the biogas was also affected by both air dosing point and flow rate, since the lowest value was observed at the highest airflow rate of the headspace dosing point, due to dilution by the N2 influx applied to the system. The highest productivity and operational efficiency were observed at this air dosing point, with this airflow (HD0.3), which corroborates with the operational results and the ecological parameters, since the microaeration at this stage promoted high bacterial and archaeal species richness and diversity, optimum functional organization, high COD and H2S removal efficiencies.
Collapse
Affiliation(s)
- M R Sousa
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - C J S Oliveira
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - J M Carneiro
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - A C Lopes
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - E Rodríguez
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - E A F Vasconcelos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - G B M Holanda
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - P G C Landim
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - M E R Silva
- Department of Civil Construction, Federal Institute of Science and Technology of Ceará, Fortaleza, Ceará, Brazil
| | - P I M Firmino
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - A B Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| |
Collapse
|
5
|
Singh S, Rinta-Kanto JM, Kettunen R, Tolvanen H, Lens P, Collins G, Kokko M, Rintala J. Anaerobic treatment of LCFA-containing synthetic dairy wastewater at 20 °C: Process performance and microbial community dynamics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 691:960-968. [PMID: 31326818 DOI: 10.1016/j.scitotenv.2019.07.136] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 07/07/2019] [Accepted: 07/09/2019] [Indexed: 06/10/2023]
Abstract
Facilitating anaerobic degradation of long-chain fatty acids (LCFA) is key for tapping the high methane production potential of the fats, oil and grease (FOG) content of dairy wastewaters. In this study, the feasibility of using high-rate granular sludge reactors for the treatment of mixed LCFA-containing synthetic dairy wastewater (SDW) was assessed at 20 °C. The effects of the LCFA concentration (33-45% of COD) and organic loading rates (2-3 gCOD/L·d) were determined using three parallel expanded granular sludge bed reactors. For the first time, long term anaerobic treatment of LCFA-containing feed at 20 °C was shown to be feasible and was linked to the microbial community dynamics in high-rate reactors. During a two-month operation, a soluble COD removal of 84-91% and COD to methane conversion of 44-51% was obtained. However, granular sludge flotation and washout occurred after two months in all reactors without volatile fatty acids (VFA) accumulation, emphasizing the need for sludge retention for long-term granular sludge reactor operation with LCFA-containing feed at low ambient temperatures. The temporal shifts in microbial community structure were studied in the high-rate treatment of SDW, and the process disturbances (elevated LCFA loading, LCFA accumulation, and batch operation) were found to decrease the microbial community diversity. The relative abundance of Methanosaeta increased with higher LCFA accumulation in the settled and flotation layer granules in the three reactors, therefore, acetoclastic methanogenesis was found to be crucial for the high-rate treatment of SDW at 20 °C. This study provides an initial understanding of the continuous anaerobic treatment of LCFA-containing industrial wastewaters at low ambient temperatures.
Collapse
Affiliation(s)
- Suniti Singh
- Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland.
| | | | - Riitta Kettunen
- Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland; Tampere Water, Viinikankatu 42 A, 33800 Tampere, Finland.
| | - Henrik Tolvanen
- Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland.
| | - Piet Lens
- Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland; UNESCO-IHE Institute for Water Education, Westvest 7, 2611AX Delft, the Netherlands.
| | - Gavin Collins
- Microbial Ecophysiology Laboratory, School of Natural Sciences, National University of Ireland, Galway, Ireland.
| | - Marika Kokko
- Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland.
| | - Jukka Rintala
- Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland.
| |
Collapse
|
6
|
Christiaens ME, De Paepe J, Ilgrande C, De Vrieze J, Barys J, Teirlinck P, Meerbergen K, Lievens B, Boon N, Clauwaert P, Vlaeminck SE. Urine nitrification with a synthetic microbial community. Syst Appl Microbiol 2019; 42:126021. [DOI: 10.1016/j.syapm.2019.126021] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Revised: 08/14/2019] [Accepted: 08/30/2019] [Indexed: 01/23/2023]
|
7
|
Gao J, Duan Y, Liu Y, Zhuang X, Liu Y, Bai Z, Ma W, Zhuang G. Long- and short-chain AHLs affect AOA and AOB microbial community composition and ammonia oxidation rate in activated sludge. J Environ Sci (China) 2019; 78:53-62. [PMID: 30665656 DOI: 10.1016/j.jes.2018.06.022] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 06/26/2018] [Accepted: 06/26/2018] [Indexed: 05/03/2023]
Abstract
Quorum sensing (QS) regulation of the composition of ammonia-oxidising archaea (AOA) and ammonia-oxidising bacteria (AOB) communities and functions in wastewater treatment was investigated. Specifically, we explored the role of N-acyl-l-homoserine lactones (AHLs) in microbial community dynamics in activated sludge. On average, the specific ammonia-oxidising-rate increased from 1.6 to 2.8 mg NH4+-N/g MLSS/hr after treatment with long-chain AHLs for 16 days, and the addition of AHLs to sludge resulted in an increased number of AOA/AOB amoA genes. Significant differences were observed in the AOA communities of control and AHL-treated cultures, but not the AOB community. Furthermore, the dominant functional AOA strains of the Crenarchaeota altered their ecological niche in response to AHL addition. These results provide evidence that AHLs play an important role in mediating AOA/AOB microbial community parameters and demonstrate the potential for application of QS to the regulation of nitrogen compound metabolism in wastewater treatment.
Collapse
Affiliation(s)
- Jie Gao
- CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu Duan
- Beijing Enterprises Water Group Limited, Beijing 100124, China
| | - Ying Liu
- CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Xuliang Zhuang
- CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yichen Liu
- Beijing Climate Change Response Research and Education Center, Department of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Zhihui Bai
- CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenlin Ma
- Beijing Climate Change Response Research and Education Center, Department of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Guoqiang Zhuang
- CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| |
Collapse
|
8
|
He Q, Chen L, Zhang S, Chen R, Wang H. Hydrodynamic shear force shaped the microbial community and function in the aerobic granular sequencing batch reactors for low carbon to nitrogen (C/N) municipal wastewater treatment. BIORESOURCE TECHNOLOGY 2019; 271:48-58. [PMID: 30261336 DOI: 10.1016/j.biortech.2018.09.102] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 09/16/2018] [Accepted: 09/18/2018] [Indexed: 06/08/2023]
Abstract
The lab-scale aerobic granules process was applied for low carbon to nitrogen (C/N < 4) wastewater treatment under different hydrodynamic shear forces. Results revealed that aerobic granules exhibited strong adaptability and stability. The aerobic granules might adopt an extracellular polymeric substances (EPS) regulating mechanism to address the changes in operational conditions, especially through growing secretion of fluorescence protein. The hydrodynamic shear force determinedly shaped and regulated the diversity and structure of dominant microbial community, briefly, reduced aeration intensity with increased time led to higher microbial richness, lower diversity and evenness, and shifts of predominant microorganisms. Phylogenetic classification of the key functional groups including bacteria related to carbon and nutrients removal, EPS production and quorum sensing (QS) presented much more differences among the reactors subject to different conditions. Therefore, the present work adds insight into the comprehensive understanding of the effect of aeration induced hydrodynamic shear force on aerobic granules.
Collapse
Affiliation(s)
- Qiulai He
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Li Chen
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Shujia Zhang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Rongfan Chen
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Hongyu Wang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China.
| |
Collapse
|
9
|
Allievi MJ, Silveira DD, Cantão ME, Filho PB. Bacterial community diversity in a full scale biofilter treating wastewater odor. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2018; 77:2014-2022. [PMID: 29722687 DOI: 10.2166/wst.2018.114] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Constantly, the odors coming from sewage plants are considered a problem by the population. The purpose of this study was to evaluate the microbial community present in a full scale biofilter used for odor treatment. The filter was packed with peat. The main gas treated was hydrogen sulphide (H2S). The removal efficiency reached 99%, with an empty bed residence time of 30 seconds. Molecular analysis can enhance our understanding of the microbial communities in biofilters treating wastewater odor. The analysis made to characterize microbial community was High-throughput 16S rRNA sequencing analysis MiSeq® Illumina. The sampling, carried out in the year 2015, was seasonal (summer and winter) and spatial (depth and position in the biofilter). In this study, a total of 206,174 raw sequence reads for six samples were analyzed using Mothur software (v 1.33.3) based on MiSeq SOP protocol. After Mothur analysis, the results of the bacterial community were explored at the Phylum and Genus levels. In this study, the efficiency removal of hydrogen sulfide reached values greater than 99% during the monitoring, and the main bacterial genera found were Acidotermus, Telmatobacter, Methylovirgula and Bryobacter representing the bacterial community active in the transformation of H2S into a system with long operating time.
Collapse
Affiliation(s)
- M J Allievi
- Department of Environmental Engineering, Federal University of Santa Catarina, Delfino Conti, Trindade, Florianópolis, Santa Catarina, Brazil E-mail:
| | - D D Silveira
- Department of Environmental Engineering, Federal University of Santa Catarina, Delfino Conti, Trindade, Florianópolis, Santa Catarina, Brazil E-mail:
| | - M E Cantão
- Empresa Brasileira de Pesquisa Agropecuária, Embrapa Suínos e Aves, BR 153, km 110, Vila Tamanduá, Concórdia, Santa Catarina, Brazil
| | - P B Filho
- Department of Environmental Engineering, Federal University of Santa Catarina, Delfino Conti, Trindade, Florianópolis, Santa Catarina, Brazil E-mail:
| |
Collapse
|
10
|
Eva S. Longterm Monitoring of Nitrification and Nitrifying Communities during Biofilter Activation of Two Marine Recirculation Aquaculture Systems (RAS). ACTA ACUST UNITED AC 2017. [DOI: 10.17352/2455-8400.000029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
11
|
Sun X, Zhu L, Wang J, Wang J, Su B, Liu T, Zhang C, Gao C, Shao Y. Toxic effects of ionic liquid 1-octyl-3-methylimidazolium tetrafluoroborate on soil enzyme activity and soil microbial community diversity. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2017; 135:201-208. [PMID: 27741461 DOI: 10.1016/j.ecoenv.2016.09.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/26/2016] [Accepted: 09/27/2016] [Indexed: 06/06/2023]
Abstract
Ionic liquids (ILs) were considered as "green" solvents and have been used widely because of their excellent properties. But ILs are not as "green" as has been suggested, and the toxic effects of ILs on organisms have been shown in recent years. In the present study, the toxic effects of the IL 1-octyl-3-methylimidazolium tetrafluoroborate ([Omim]BF4) on soil enzyme activity and soil microbial communities at three different concentrations (1.0, 5.0 and 10.0mg/kg) and a control treatment over 40 days of incubation time (sampled on days 10, 20, 30 and 40) were examined under laboratory conditions. The concentrations of [Omim]BF4 in soils were detected by high performance liquid chromatography (HPLC) and the results indicated that [Omim]BF4 were maintained stable in the soil during the exposure period. However, the enzyme activity results showed that urease activity was stimulated on day 20 and then decreased after 30 days of incubation. The activity of β-glucosidase was stimulated after 20 days of incubation in both treatment groups. Moreover, both dehydrogenase and acid phosphatase were inhibited at a high level (10.0mg/kg) only on day 20. The analysis of terminal restriction fragment length polymorphism (T-RFLP) revealed that the soil microbial community structures were altered by [Omim]BF4 and that the soil microbial diversity and evenness of high levels (5.0mg/kg and 10.0mg/kg) treatments were decreased. Moreover, the dominant structure of the microbial communities was not changed by [Omim]BF4. Furthermore, the abundance of the ammonia monooxygenase (amoA) genes of both ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) was examined using real time polymerase chain reaction (RT-PCR). The results revealed that the copy numbers of the amoA-gene were decreased by [Omim]BF4 with the 5.0 and 10.0mg/kg treatments. Based on the experiment, we concluded that high levels (5.0 and 10.0mg/kg) of [Omim]BF4 could have significantly toxic effects on soil enzyme activities and the diversity of the microbial communities.
Collapse
Affiliation(s)
- Xi Sun
- Key Laboratory of Agriculture Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Taian 271018, PR China
| | - Lusheng Zhu
- Key Laboratory of Agriculture Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Taian 271018, PR China.
| | - Jinhua Wang
- Key Laboratory of Agriculture Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Taian 271018, PR China
| | - Jun Wang
- Key Laboratory of Agriculture Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Taian 271018, PR China
| | - Benying Su
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China.
| | - Tong Liu
- Key Laboratory of Agriculture Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Taian 271018, PR China
| | - Cheng Zhang
- Key Laboratory of Agriculture Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Taian 271018, PR China
| | - Chong Gao
- Key Laboratory of Agriculture Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Taian 271018, PR China
| | - Yuting Shao
- Key Laboratory of Agriculture Environment in Universities of Shandong, College of Resources and Environment, Shandong Agricultural University, Taian 271018, PR China
| |
Collapse
|
12
|
Cruvellier N, Poughon L, Creuly C, Dussap CG, Lasseur C. Growth modelling of Nitrosomonas europaea ATCC® 19718 and Nitrobacter winogradskyi ATCC® 25391: A new online indicator of the partial nitrification. BIORESOURCE TECHNOLOGY 2016; 220:369-377. [PMID: 27595702 DOI: 10.1016/j.biortech.2016.08.090] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 08/23/2016] [Accepted: 08/24/2016] [Indexed: 06/06/2023]
Abstract
The aim of the present work was to study the growth of two nitrifying bacteria. For modelling the nitrifying subsystem of the MELiSSA loop, Nitrosomonas europaea ATCC® 19718 and Nitrobacter winogradskyi ATCC® 25931 were grown separately and in cocultures. The kinetic parameters of a stoichiometric mass balanced Pirt model were identified: μmax=0.054h(-1), decay rate b=0.003h(-1) and maintenance rate m=0.135gN-NH4(+)·gX(-1)·h(-1) for Nitrosomonas europaea; μmax=0.024h(-1), b=0.001h(-1) and m=0.467gN-NO2(-)·gX(-1)·h(-1) for Nitrobacter winogradskyi. A predictive structured model of nitrification in co-culture was developed. The online evolution of the addition of KOH is correlated to the nitritation; the dissolved oxygen concentration is correlated to both nitritation and nitratation. The model suitably represents these two variables so that transient partial nitrification is assessed. This is a clue for avoiding partial nitrification by predictive functional control.
Collapse
Affiliation(s)
- Nelly Cruvellier
- Université Clermont Auvergne, Institut Pascal, UMR CNRS 6602, TSA 60026, CS 60026, F-63178 Aubière cedex, France
| | - Laurent Poughon
- Université Clermont Auvergne, Institut Pascal, UMR CNRS 6602, TSA 60026, CS 60026, F-63178 Aubière cedex, France.
| | - Catherine Creuly
- Université Clermont Auvergne, Institut Pascal, UMR CNRS 6602, TSA 60026, CS 60026, F-63178 Aubière cedex, France
| | - C-Gilles Dussap
- Université Clermont Auvergne, Institut Pascal, UMR CNRS 6602, TSA 60026, CS 60026, F-63178 Aubière cedex, France
| | | |
Collapse
|
13
|
Zou W, Xue B, Zhi W, Zhao T, Yang D, Qiu Z, Shen Z, Li J, Zhang B, Wang J. Effects of antibiotic resistance genes on the performance and stability of different microbial aggregates in a granular sequencing batch reactor. JOURNAL OF HAZARDOUS MATERIALS 2016; 304:343-351. [PMID: 26590870 DOI: 10.1016/j.jhazmat.2015.10.057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 10/19/2015] [Accepted: 10/25/2015] [Indexed: 06/05/2023]
Abstract
Antibiotic resistance genes (ARGs) have emerged as key factors in wastewater environmental contaminants and continue to pose a challenge for wastewater treatment processes. With the aim of investigating the performance of granular sludge system when treating wastewater containing a considerable amount of ARGs, a lab-scale granular sequencing batch reactor (GSBR) where flocculent and granular sludge coexisted was designed. The results showed that after inoculation of donor strain NH4(+)-N purification efficiency diminished from 94.7% to 32.8% and recovered to 95.2% after 10 days. Meanwhile, RP4 plasmid had varying effects on different forms of microbial aggregates. As the size of aggregates increased, the abundance of RP4 in sludge decreased. The residence time of RP4 in granules with particle size exceeding 0.9 mm (14 days) was far shorter than that in flocculent sludge (26 days). Therefore, our studies conclude that with increasing number of ARGs being detected in wastewater, the use of granular sludge system in wastewater treatment processes will allow the reduction of ARGs transmissions and lessen potential ecological threats.
Collapse
Affiliation(s)
- Wenci Zou
- Tianjin Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, PR China
| | - Bin Xue
- Tianjin Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, PR China
| | - Weijia Zhi
- Tianjin Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, PR China
| | - Tianyu Zhao
- Tianjin Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, PR China
| | - Dong Yang
- Tianjin Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, PR China
| | - Zhigang Qiu
- Tianjin Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, PR China
| | - Zhiqiang Shen
- Tianjin Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, PR China
| | - Junwen Li
- Tianjin Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, PR China
| | - Bin Zhang
- Tianjin Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, PR China.
| | - Jingfeng Wang
- Tianjin Institute of Health and Environmental Medicine, Tianjin Key Laboratory of Risk Assessment and Control for Environment and Food Safety, Tianjin 300050, PR China.
| |
Collapse
|
14
|
Louca S, Doebeli M. Transient dynamics of competitive exclusion in microbial communities. Environ Microbiol 2015; 18:1863-74. [DOI: 10.1111/1462-2920.13058] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 09/15/2015] [Indexed: 12/23/2022]
Affiliation(s)
- Stilianos Louca
- Biodiversity Research Centre; University of British Columbia; Vancouver BC V6T 1Z4 Canada
| | - Michael Doebeli
- Department of Zoology; University of British Columbia; Vancouver BC V6T 1Z4 Canada
- Department of Mathematics; University of British Columbia; Vancouver BC V6T 1Z2 Canada
| |
Collapse
|
15
|
Ge S, Wang S, Yang X, Qiu S, Li B, Peng Y. Detection of nitrifiers and evaluation of partial nitrification for wastewater treatment: A review. CHEMOSPHERE 2015; 140:85-98. [PMID: 25796420 DOI: 10.1016/j.chemosphere.2015.02.004] [Citation(s) in RCA: 220] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 12/14/2014] [Accepted: 02/01/2015] [Indexed: 06/04/2023]
Abstract
Partial nitrification has gained broad interests in the biological nitrogen removal (BNR) from wastewater, since it alleviates carbon limitation issues and acts as a shortcut nitrogen removal system combined with anaerobic ammonium oxidation (Anammox) process. The occurrence and maintenance of partial nitrification relies on various conditions, which favor ammonium oxidizing bacteria (AOB) but inhibit or limit nitrite oxidizing bacteria (NOB). The studies of the AOB and NOB activities have been conducted by state-of-the-art molecular techniques, such as Polymerase Chain Reaction (PCR), Quantitative PCR, denaturing gradient gel electrophoresis (DGGE), Fluorescence in situ hybridization (FISH) technique, Terminal Restriction Fragment Length Polymorphism (T-RFLP), Live/Dead BacLight, and quinone profile. Furthermore, control strategies for obtaining partial nitrification are mainly focused on the pH, temperature, dissolved oxygen concentration, real-time aeration control, sludge retention time, substrate concentration, alternating anoxic and aerobic operation, inhibitor and ultrasonic treatment. Existing problems and further perspectives for the scale-up of partial nitrification are also proposed and suggested.
Collapse
Affiliation(s)
- Shijian Ge
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
| | - Shanyun Wang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Xiong Yang
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Shuang Qiu
- Department of Biology, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Baikun Li
- Department of Civil and Environmental Engineering, University of Connecticut, Storrs, CT 06269, USA
| | - Yongzhen Peng
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| |
Collapse
|
16
|
Ryu BG, Kim W, Nam K, Kim S, Lee B, Park MS, Yang JW. A comprehensive study on algal-bacterial communities shift during thiocyanate degradation in a microalga-mediated process. BIORESOURCE TECHNOLOGY 2015; 191:496-504. [PMID: 25911193 DOI: 10.1016/j.biortech.2015.03.136] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 03/25/2015] [Accepted: 03/27/2015] [Indexed: 06/04/2023]
Abstract
Changes in algal and bacterial communities during thiocyanate (SCN(-)) decomposition in a microalga-mediated process were studied. Pyrosequencing indicated that Thiobacillus bacteria and Micractinium algae predominated during SCN(-) hydrolysis, even after its complete degradation. Principal components analysis and evenness profiles (based on the Pareto-Lorenz curve) suggested that the changes in the bacterial communities were driven by nitrogen and sulfur oxidation, pH changes, and photoautotrophic conditions. The populations of predominant microalgae remained relatively stable during SCN(-) hydrolysis, but the proportion of bacteria - especially nitrifying bacteria - fluctuated. Thus, the initial microalgal population may be crucial in determining which microorganisms dominate when the preferred nitrogen source becomes limited. The results also demonstrated that microalgae and SCN(-)-hydrolyzing bacteria can coexist, that microalgae can be effectively used with these bacteria to completely treat SCN(-), and that the structure of the algal-bacterial community is more stable than the community of nitrifying bacteria alone during SCN(-) degradation.
Collapse
Affiliation(s)
- Byung-Gon Ryu
- Environmental and Energy Program, KAIST, 291 Daehak-ro, Yuseong, Daejeon, Republic of Korea; Decontamination and Decommissioning Research Division, Korea Atomic Energy Research Institute (KAERI), 989-111 Daedukdaero, Yuseong-gu, Daejeon, Republic of Korea
| | - Woong Kim
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Kibok Nam
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Sungwhan Kim
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Bongsoo Lee
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Min S Park
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Ji-Won Yang
- Department of Chemical and Biomolecular Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, Republic of Korea; Advanced Biomass R&D Center, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon, Republic of Korea.
| |
Collapse
|
17
|
De Vrieze J, Raport L, Willems B, Verbrugge S, Volcke E, Meers E, Angenent LT, Boon N. Inoculum selection influences the biochemical methane potential of agro-industrial substrates. Microb Biotechnol 2015; 8:776-86. [PMID: 25756301 PMCID: PMC4554466 DOI: 10.1111/1751-7915.12268] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 01/08/2015] [Accepted: 01/09/2015] [Indexed: 12/22/2022] Open
Abstract
Obtaining a reliable estimation of the methane potential of organic waste streams in anaerobic digestion, for which a biochemical methane potential (BMP) test is often used, is of high importance. Standardization of this BMP test is required to ensure inter-laboratory repeatability and accuracy of the BMP results. Therefore, guidelines were set out; yet, these do not provide sufficient information concerning origin of and the microbial community in the test inoculum. Here, the specific contribution of the methanogenic community on the BMP test results was evaluated. The biomethane potential of four different substrates (molasses, bio-refinery waste, liquid manure and high-rate activated sludge) was determined by means of four different inocula from full-scale anaerobic digestion plants. A significant effect of the selected inoculum on the BMP result was observed for two out of four substrates. This inoculum effect could be attributed to the abundance of methanogens and a potential inhibiting effect in the inoculum itself, demonstrating the importance of inoculum selection for BMP testing. We recommend the application of granular sludge as an inoculum, because of its higher methanogenic abundance and activity, and protection from bulk solutions, compared with other inocula.
Collapse
Affiliation(s)
- Jo De Vrieze
- Laboratory of Microbial Ecology and Technology (LabMET), Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
| | - Linde Raport
- Laboratory of Microbial Ecology and Technology (LabMET), Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
- InnolabDerbystraat 223, Sint-Denijs-Westrem, 9051, Belgium
| | | | - Silke Verbrugge
- Laboratory of Microbial Ecology and Technology (LabMET), Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
| | - Eveline Volcke
- Department of Biosystems Engineering, Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
| | - Erik Meers
- Laboratory of Analytical Chemistry and Applied Biochemistry, Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
| | - Largus T Angenent
- Department of Biological and Environmental Engineering, Cornell UniversityIthaca, NY, 14853, USA
| | - Nico Boon
- Laboratory of Microbial Ecology and Technology (LabMET), Ghent UniversityCoupure Links 653, Gent, B-9000, Belgium
| |
Collapse
|
18
|
Vannecke TPW, Volcke EIP. Modelling microbial competition in nitrifying biofilm reactors. Biotechnol Bioeng 2015; 112:2550-61. [DOI: 10.1002/bit.25680] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/10/2015] [Accepted: 06/10/2015] [Indexed: 11/07/2022]
Affiliation(s)
- T. P. W. Vannecke
- Department of Biosystems Engineering; Ghent University; Coupure Links 653, 9000 Ghent Belgium
| | - E. I. P. Volcke
- Department of Biosystems Engineering; Ghent University; Coupure Links 653, 9000 Ghent Belgium
| |
Collapse
|
19
|
Ma F, Li A, Li B, Cui Z, Shi C, Zhou B. Prolonged starvation and subsequent recovery of nitrification process in a simulated photovoltaic aeration SBR. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:10778-10787. [PMID: 25758416 DOI: 10.1007/s11356-015-4246-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 02/17/2015] [Indexed: 06/04/2023]
Abstract
The ability of a new SBR (sequencing batch reactor) based on simulating photovoltaic aeration for maintaining nitrification activity under a 25-day starvation period was studied. The activity and abundance of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) and the diversity of AOB were investigated. The measured biomass decay rates were 0.017 day(-1) and 0.029 day(-1) for AOB and NOB, respectively. These decay rates correlated well with AOB and NOB population quantified by real-time PCR. The recovery of ammonia oxidation rate and nitrite oxidation rate needed 4 and 7 days, respectively, indicating that NOB was more affected than AOB by starvation conditions. According to the real-time PCR results, Nitrospira was the dominant NOB in the reactor. Phylogenetic analysis indicated that Nitrosomonas oligotropha cluster was the dominant major cluster before and after starvation. Moreover, Pareto-Lorenz evenness distribution curves were plotted to interpret the interspecies abundance of AOB; the results suggested that AOB community possessed a balanced structure with medium Fo (Functional organization). Thus, the community can potentially deal with changing environmental conditions (e.g., starvation) and preserve its functionality according to the concept of functional redundancy.
Collapse
Affiliation(s)
- Fangshu Ma
- Department of Environmental Engineering, School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | | | | | | | | | | |
Collapse
|
20
|
Liu J, Wang J, Gao G, Bartlam MG, Wang Y. Distribution and diversity of fungi in freshwater sediments on a river catchment scale. Front Microbiol 2015; 6:329. [PMID: 25954259 PMCID: PMC4404825 DOI: 10.3389/fmicb.2015.00329] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 04/01/2015] [Indexed: 11/16/2022] Open
Abstract
Fungal communities perform essential functions in biogeochemical cycles. However, knowledge of fungal community structural changes in river ecosystems is still very limited. In the present study, we combined culture-dependent and culture-independent methods to investigate fungal distribution and diversity in sediment on a regional scale in the Songhua River catchment, located in North-East Asia. A total of 147 samples over the whole river catchment were analyzed. The results showed that compared to the mainstream, the tributaries have a higher fungal community organization and culturable fungal concentration, but possess lower community dynamics as assessed by denaturing gradient gel electrophoresis (DGGE). Furthermore, phylogenetic analysis of DGGE bands showed that Ascomycota and Basidiomycota were the predominant community in the Songhua River catchment. Redundancy analysis revealed that longitude was the primary factor determining the variation of fungal community structure, and fungal biomass was mainly related to the total nutrient content. Our findings provide new insights into the characteristics of fungal community distribution in a temperate zone river at a regional scale, and demonstrate that fungal dispersal is restricted by geographical barriers in a whole river catchment.
Collapse
Affiliation(s)
- Jie Liu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University Tianjin, China
| | - Jianan Wang
- Department of Environmental Science and Engineering, Nankai University Binhai College Tianjin, China
| | - Guanghai Gao
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University Tianjin, China
| | - Mark G Bartlam
- State Key Laboratory of Medicinal Chemical Biology and College of Life Sciences, Nankai University Tianjin, China
| | - Yingying Wang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University Tianjin, China
| |
Collapse
|
21
|
Inoculum selection is crucial to ensure operational stability in anaerobic digestion. Appl Microbiol Biotechnol 2014; 99:189-99. [DOI: 10.1007/s00253-014-6046-3] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 08/19/2014] [Accepted: 08/24/2014] [Indexed: 01/24/2023]
|
22
|
Simultaneous in-situ excess sludge reduction and removal of organic carbon and nitrogen by a pilot-scale continuous aerobic–anaerobic coupled (CAAC) process for deeply treatment of soybean wastewater. Biochem Eng J 2014. [DOI: 10.1016/j.bej.2014.01.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
23
|
Guadie A, Xia S, Zhang Z, Zeleke J, Guo W, Ngo HH, Hermanowicz SW. Effect of intermittent aeration cycle on nutrient removal and microbial community in a fluidized bed reactor-membrane bioreactor combo system. BIORESOURCE TECHNOLOGY 2014; 156:195-205. [PMID: 24508900 DOI: 10.1016/j.biortech.2014.01.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 01/02/2014] [Accepted: 01/04/2014] [Indexed: 06/03/2023]
Abstract
Effect of intermittent aeration cycle (IAC=15/45-60/60min) on nutrient removal and microbial community structure was investigated using a novel fluidized bed reactor-membrane bioreactor (FBR-MBR) combo system. FBR alone was found more efficient for removing PO4-P (>85%) than NH4-N (<40%) and chemical oxygen demand (COD<35%). However, in the combo system, COD and NH4-N removals were almost complete (>98%). Efficient nitrification, stable mixed liquor suspended solid and reduced transmembrane pressure was also achieved. Quantitative real-time polymerase chain reaction results of total bacteria 16S rRNA gene copies per mL of mixed-liquor varied from (2.48±0.42)×10(9) initial to (2.74±0.10)×10(8), (6.27±0.16)×10(9) and (9.17±1.78)×10(9) for 15/45, 45/15 and 60/60min of IACs, respectively. The results of clone library analysis revealed that Proteobacteria (59%), Firmicutes (12%) and Bacteroidetes (11%) were the dominant bacterial group in all samples. Overall, the combo system performs optimum nutrient removal and host stable microbial communities at 45/15min of IAC.
Collapse
Affiliation(s)
- Awoke Guadie
- UNEP-Tongji Institute of Environment for Sustainable Development, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Siqing Xia
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
| | - Zhiqiang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Jemaneh Zeleke
- Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Wenshan Guo
- Center for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Huu Hao Ngo
- Center for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Slawomir W Hermanowicz
- Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720, United States
| |
Collapse
|
24
|
Characterization of Denitrifying Phosphorus Removal Microorganisms in a Novel Two-Sludge Process by Combining Chemical with Microbial Analysis. J CHEM-NY 2014. [DOI: 10.1155/2014/360503] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The present work focuses on the investigation of denitrifying phosphorus removal organisms (DPB) in a novel two-sludge denitrifying phosphorus removal process by combining chemical with microbial analysis. When the two-sludge process operated stably over one year, good phosphorus (P) release and P uptake performance of activated sludge samples collected from this process were present in anaerobic and anoxic conditions, respectively, via batch test, showing that the ratio of P release specific rate to P uptake specific rate was 1.31. The analysis of energy dispersive spectrometry (EDS) showed that P content of activated sludge samples collected at the end of anoxic phase was 12.3% of dry weight, further demonstrating the existence of microorganisms responsible for phosphorus removal in this two-sludge process. From polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis, the presence of microorganisms mostly belonging to the phyla Firmicutes and Proteobacteria was observed, previously evidenced in the phosphorus removal wastewater treatment process. Fluorescence in situ hybridization (FISH) quantitative analysis showed thatAccumulibacterresponsible for phosphorus removal was dominant in this two-sludge process, accounting for 69.7% of all bacteria in activated sludge. These results obtained from chemical and microbial analysis in this study suggested that denitrifying phosphorus removal microorganisms were completely enriched in the two-sludge process proposed here.
Collapse
|
25
|
Marzorati M, Negroni A, Fava F, Verstraete W, Boon N. Application of a molecular based approach for the early detection of short term 3-chloroaniline shock loads on activated sludge bacterial community and functionality. N Biotechnol 2013; 30:763-71. [DOI: 10.1016/j.nbt.2013.07.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 05/06/2013] [Accepted: 07/19/2013] [Indexed: 11/30/2022]
|
26
|
Regueiro L, Veiga P, Figueroa M, Alonso-Gutierrez J, Stams AJ, Lema JM, Carballa M. Relationship between microbial activity and microbial community structure in six full-scale anaerobic digesters. Microbiol Res 2012; 167:581-9. [DOI: 10.1016/j.micres.2012.06.002] [Citation(s) in RCA: 144] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 05/21/2012] [Accepted: 06/05/2012] [Indexed: 10/28/2022]
|
27
|
Prevalence of Nitrosomonas cluster 7 populations in the ammonia-oxidizing community of a submerged membrane bioreactor treating urban wastewater under different operation conditions. Bioprocess Biosyst Eng 2012; 36:901-10. [PMID: 22976820 DOI: 10.1007/s00449-012-0823-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 09/01/2012] [Indexed: 10/27/2022]
Abstract
A pilot-scale ultrafiltration membrane bioreactor (MBR) was used for the aerobic treatment of urban wastewater in four experimental stages influenced by seasonal temperature and different sets of operation conditions. The structure of the ammonia-oxidizing bacteria (AOB) community was profiled by temperature gradient gel electrophoresis (TGGE), based on the amplification and separation of partial ammonia-monoxygenase subunit A (amoA) genes. Canonical correspondence analysis revealed that temperature, hydraulic retention time and percentage of ammonia removal had a significant effect on the fingerprints of AOB communities. Phylogenetic analysis conducted on amoA/AmoA sequences of reamplified TGGE bands showed, however, that closely related ammonia-oxidizing populations inhabited the sludge of the MBR in all experimental stages. Nitrosomonas cluster 7 populations (N. europaea-N. eutropha cluster) prevailed under all conditions tested, even when the MBR was operated under complete biomass retention or at low temperatures, suggesting that the high ammonia concentrations in the system were determinant to select r-strategist AOB.
Collapse
|
28
|
Lebrero R, Rodríguez E, Pérez R, García-Encina PA, Muñoz R. Abatement of odorant compounds in one- and two-phase biotrickling filters under steady and transient conditions. Appl Microbiol Biotechnol 2012; 97:4627-38. [DOI: 10.1007/s00253-012-4247-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2012] [Revised: 06/12/2012] [Accepted: 06/14/2012] [Indexed: 10/28/2022]
|
29
|
Xu XY, Feng LJ, Zhu L, Xu J, Ding W, Qi HY. Biofilm formation and microbial community analysis of the simulated river bioreactor for contaminated source water remediation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2012; 19:1584-1593. [PMID: 22120124 DOI: 10.1007/s11356-011-0649-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 10/18/2011] [Indexed: 05/31/2023]
Abstract
BACKGROUND, AIM, AND SCOPE The start-up pattern of biofilm remediation system affects the biofilm characteristics and operating performances. The objective of this study was to evaluate the performances of the contaminated source water remediation systems with different start-up patterns in view of the pollutants removal performances and microbial community succession. METHODS The operating performances of four lab-scale simulated river biofilm reactors were examined which employed different start-up methods (natural enrichment and artificial enhancement via discharging sediment with influent velocity gradient increase) and different bio-fillers (Elastic filler and AquaMats® ecobase). At the same time, the microbial communities of the bioreactors in different phases were analyzed by polymerase chain reaction, denaturing gradient gel electrophoresis, and sequencing. RESULTS AND DISCUSSION The pollutants removal performances became stable in the four reactors after 2 months' operation, with ammonia nitrogen and permanganate index (COD(Mn)) removal efficiencies of 84.41-94.21% and 69.66-76.60%, respectively. The biomass of mature biofilm was higher in the bioreactors by artificial enhancement than that by natural enrichment. Microbial community analysis indicated that elastic filler could enrich mature biofilm faster than AquaMats®. The heterotrophic bacteria diversity of biofilm decreased by artificial enhancement, which favored the ammonia-oxidizing bacteria (AOB) developing on the bio-fillers. Furthermore, Nitrosomonas- and Nitrosospira-like AOB coexisted in the biofilm, and Pseudomonas sp., Sphaerotilus sp., Janthinobacterium sp., Corynebacterium aurimucosum were dominant in the oligotrophic niche. CONCLUSION Artificial enhancement via the combination of sediment discharging and influent velocity gradient increasing could enhance the biofilm formation and autotrophic AOB enrichment in oligotrophic niche.
Collapse
Affiliation(s)
- Xiang-Yang Xu
- Department of Environmental Engineering, Zhejiang University, Hangzhou, People's Republic of China
| | | | | | | | | | | |
Collapse
|
30
|
Lubarsky HV, Gerbersdorf SU, Hubas C, Behrens S, Ricciardi F, Paterson DM. Impairment of the bacterial biofilm stability by triclosan. PLoS One 2012; 7:e31183. [PMID: 22523534 PMCID: PMC3327702 DOI: 10.1371/journal.pone.0031183] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 01/04/2012] [Indexed: 11/18/2022] Open
Abstract
The accumulation of the widely-used antibacterial and antifungal compound triclosan (TCS) in freshwaters raises concerns about the impact of this harmful chemical on the biofilms that are the dominant life style of microorganisms in aquatic systems. However, investigations to-date rarely go beyond effects at the cellular, physiological or morphological level. The present paper focuses on bacterial biofilms addressing the possible chemical impairment of their functionality, while also examining their substratum stabilization potential as one example of an important ecosystem service. The development of a bacterial assemblage of natural composition – isolated from sediments of the Eden Estuary (Scotland, UK) – on non-cohesive glass beads (<63 µm) and exposed to a range of triclosan concentrations (control, 2 – 100 µg L−1) was monitored over time by Magnetic Particle Induction (MagPI). In parallel, bacterial cell numbers, division rate, community composition (DGGE) and EPS (extracellular polymeric substances: carbohydrates and proteins) secretion were determined. While the triclosan exposure did not prevent bacterial settlement, biofilm development was increasingly inhibited by increasing TCS levels. The surface binding capacity (MagPI) of the assemblages was positively correlated to the microbial secreted EPS matrix. The EPS concentrations and composition (quantity and quality) were closely linked to bacterial growth, which was affected by enhanced TCS exposure. Furthermore, TCS induced significant changes in bacterial community composition as well as a significant decrease in bacterial diversity. The impairment of the stabilization potential of bacterial biofilm under even low, environmentally relevant TCS levels is of concern since the resistance of sediments to erosive forces has large implications for the dynamics of sediments and associated pollutant dispersal. In addition, the surface adhesive capacity of the biofilm acts as a sensitive measure of ecosystem effects.
Collapse
Affiliation(s)
- Helen V. Lubarsky
- Institute of Hydraulic Engineering, University Stuttgart, Stuttgart, Germany
- Sediment Ecology Research Group, Scottish Ocean Institute, School of Biology, University of St. Andrews, St. Andrews, Scotland, United Kingdom
| | - Sabine U. Gerbersdorf
- Institute of Hydraulic Engineering, University Stuttgart, Stuttgart, Germany
- * E-mail:
| | - Cédric Hubas
- Département Milieux et Peuplements Aquatiques (DMPA), Muséum National d’Histoire Naturelle, UMR BOREA (Biologie des organismes et écosystèmes aquatiques) MNHN-CNRS-UPMC-IRD, Paris, France
| | - Sebastian Behrens
- Geomicrobiology/Microbial Ecology Group, Centre for Applied Geosciences (ZAG), Eberhard-Karls-University Tübingen, Tübingen, Germany
| | | | - David M. Paterson
- Sediment Ecology Research Group, Scottish Ocean Institute, School of Biology, University of St. Andrews, St. Andrews, Scotland, United Kingdom
| |
Collapse
|
31
|
Farges B, Poughon L, Roriz D, Creuly C, Dussap CG, Lasseur C. Axenic Cultures of Nitrosomonas europaea and Nitrobacter winogradskyi in Autotrophic Conditions: a New Protocol for Kinetic Studies. Appl Biochem Biotechnol 2012; 167:1076-91. [DOI: 10.1007/s12010-012-9651-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Accepted: 03/09/2012] [Indexed: 11/28/2022]
|
32
|
Zielińska M, Bernat K, Cydzik-Kwiatkowska A, Sobolewska J, Wojnowska-Baryła I. Nitrogen removal from wastewater and bacterial diversity in activated sludge at different COD/N ratios and dissolved oxygen concentrations. J Environ Sci (China) 2012; 24:990-998. [PMID: 23505865 DOI: 10.1016/s1001-0742(11)60867-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The impact of the organic carbon to nitrogen ratio (chemical oxygen demand (COD)/N) in wastewater and dissolved oxygen (DO) concentration on carbon and nitrogen removal efficiency, and total bacteria and ammonia-oxidizing bacteria (AOB) communities in activated sludge in constantly aerated sequencing batch reactors (SBRs) was determined. At DO of 0.5 and 1.5 mg O2/L during the aeration phase, the efficiency of ammonia oxidation exceeded 90%, with nitrates as the main product. Nitrification and denitrification achieved under the same operating conditions suggested the simultaneous course of these processes. The most effective nitrogen elimination (above 50%) was obtained at the COD/N ratio of 6.8 and DO of 0.5 mg O2/L. Total bacterial diversity was similar in all experimental series, however, for both COD/N ratios of 6.8 and 0.7, higher values were observed at DO of 0.5 mg O2/L. The diversity and abundance of AOB were higher in the reactors with the COD/N ratio of 0.7 in comparison with the reactors with the COD/N of 6.8. For both COD/N ratios applied, the AOB population was not affected by oxygen concentration. Amplicons with sequences indicating membership of the genus Nitrosospira were the determinants of variable technological conditions.
Collapse
Affiliation(s)
- Magdalena Zielińska
- Department of Environmental Biotechnology, University of Warmia and Mazury in Olsztyn, Stoneczna St. 45G, 10-709 Olsztyn, Poland.
| | | | | | | | | |
Collapse
|
33
|
Teles FR, Teles RP, Uzel NG, Song XQ, Torresyap G, Socransky SS, Haffajee AD. Early microbial succession in redeveloping dental biofilms in periodontal health and disease. J Periodontal Res 2011; 47:95-104. [PMID: 21895662 DOI: 10.1111/j.1600-0765.2011.01409.x] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND AND OBJECTIVE The development of dental biofilms after professional plaque removal is very rapid. However, it is not clear whether most bacterial species return at similar rates in periodontally healthy and periodontitis subjects or if there are differences in bacterial recolonization between supragingival and subgingival biofilms in periodontal health and disease. MATERIAL AND METHODS Supragingival and subgingival plaque samples were taken separately from 28 teeth in 38 healthy and 17 periodontitis subjects immediately after professional cleaning. Samples were taken again from seven teeth in randomly selected quadrants after 1, 2, 4 and 7 d of no oral hygiene and analyzed using checkerboard DNA-DNA hybridization. The percentage of DNA probe counts were averaged within subjects at each time-point. Ecological succession was determined using a modified moving-window analysis. RESULTS Succession in supragingival biofilms from subjects with periodontitis and from healthy individuals was similar. At 1 d, Streptococcus mitis and Neisseria mucosa showed increased proportions, followed by Capnocytophaga gingivalis, Eikenella corrodens, Veillonella parvula and Streptococcus oralis at 1-4 d. At 4-7 d, Campylobacter rectus, Campylobacter showae, Prevotella melaninogenica and Prevotella nigrescens became elevated. Subgingival plaque redevelopment was slower and very different from supragingival plaque redevelopment. Increased proportions were first observed for S. mitis, followed by V. parvula and C. gingivalis and, at 7 d, by Capnocytophaga sputigena and P. nigrescens. No significant increase in the proportions of periodontal pathogens was observed in any of the clinical groups or locations. CONCLUSION There is a defined order in bacterial species succession in early supragingival and subgingival biofilm redevelopment after professional cleaning.
Collapse
Affiliation(s)
- F R Teles
- Department of Periodontology, The Forsyth Institute, Cambridge, MA 02142, USA
| | | | | | | | | | | | | |
Collapse
|
34
|
Munz G, Lubello C, Oleszkiewicz JA. Factors affecting the growth rates of ammonium and nitrite oxidizing bacteria. CHEMOSPHERE 2011; 83:720-725. [PMID: 21345481 DOI: 10.1016/j.chemosphere.2011.01.058] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 01/26/2011] [Accepted: 01/28/2011] [Indexed: 05/30/2023]
Abstract
The maximum specific growth rates of both ammonium oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) were investigated under varying aerobic solids retention time (SRT(a)) and in the presence/absence of anoxic (alternating) conditions. Two bench SBRs, reactor R1 and R2, were run in parallel for 150d. Reactor R1 was operated in aerobic conditions while R2 operated in alternating anoxic/aerobic conditions. The feed (synthetic wastewater), temperature, hydraulic retention time and mixing were identical in both reactors. The SRT(a) in both reactors was, sequentially, set at four values: 5, 4, 3 and 2d. Kinetic tests with the biomasses from both reactors were carried out to estimate the maximum specific growth rates (μ(max)) at each tested SRT(a) and decay rates, in both aerobic and anoxic conditions. The kinetic parameters of nitrifier were estimated through the calibration of a two step nitrification-denitrification activated sludge model. The results point to a slightly higher μ(max,AOB) and μ(max,NOB) in alternating conditions, while both μ(max,AOB) and μ(max,NOB) were shown not to vary in the tested range of SRT(a) (from 2 to 5d) at 20°C. They were relatively high when compared to literature data: 1.05d(-1)<μ(max,AOB)<1.4d(-1) and 0.91d(-1)<μ(max,NOB)<1.31d(-1). The decay coefficients of both AOB and NOB were much higher in aerobic (from 0.22d(-1) to 0.28d(-1)) than in anoxic (0.04d(-1) to 0.16d(-1)) conditions both in R1 and R2, which explained the higher nitrification rates observed in the alternating reactor.
Collapse
Affiliation(s)
- Giulio Munz
- Department of Civil Engineering, University of Manitoba, Winnipeg, Manitoba, Canada R3T 5V6.
| | | | | |
Collapse
|
35
|
Microbial Resource Management revisited: successful parameters and new concepts. Appl Microbiol Biotechnol 2011; 90:861-71. [DOI: 10.1007/s00253-011-3223-5] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Revised: 02/24/2011] [Accepted: 02/24/2011] [Indexed: 12/21/2022]
|
36
|
Integrating microbial ecology in bioprocess understanding: the case of gas biofiltration. Appl Microbiol Biotechnol 2011; 90:837-49. [PMID: 21424795 DOI: 10.1007/s00253-011-3191-9] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2010] [Revised: 02/25/2011] [Accepted: 02/27/2011] [Indexed: 10/18/2022]
Abstract
Biofilters are packed-bed bioreactors where contaminants, once transferred from the gas phase to the biofilm, are oxidized by diverse and complex communities of attached microorganisms. Over the last decade, more and more studies aimed at opening the back box of biofiltration by unraveling the biodiversity-ecosystem function relationship. In this review, we report the insights provided by the microbial ecology approach in biofilters and we emphasize the parallels existing with other engineered ecosystems used for wastewater treatment, as they all constitute relevant model ecosystems to explore ecological issues. We considered three characteristic ecological indicators: the density, the diversity, and the structure of the microbial community. Special attention was paid to the temporal and spatial dynamics of each indicator, insofar as it can disclose the potential relationship, or absence of relation, with any operating or functional parameter. We also focused on the impact of disturbance regime on the microbial community structure, in terms of resistance, resilience, and memory. This literature review led to mitigated conclusions in terms of biodiversity-ecosystem function relationship. Depending on the environmental system itself and the way it is investigated, the spatial and temporal dynamics of the microbial community can be either correlated (e.g., spatial stratification) or uncoupled (e.g., temporal instability) to the ecosystem function. This lack of generality shows the limits of current 16S approach in complex ecosystems, where a functional approach may be more suitable.
Collapse
|
37
|
Munz G, Mori G, Vannini C, Lubello C. Kinetic parameters and inhibition response of ammonia- and nitrite-oxidizing bacteria in membrane bioreactors and conventional activated sludge processes. ENVIRONMENTAL TECHNOLOGY 2010; 31:1557-1564. [PMID: 21275252 DOI: 10.1080/09593331003793828] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Ammonium and nitrite oxidizing biomasses (AOB and NOB) were investigated in parallel pilot plants: a membrane bioreactor (MBR) and a conventional activated sludge process (CASP) fed with domestic wastewater. The kinetics of AOB and NOB were monitored through titrimetric tests. The maximum specific growth rate of the AOB (micro(max,AOB)) was affected by the solids' retention time (SRT) maintained during the start up: by varying the start up SRT from 20 d to 8 d, micro(max,AOB) in the CASP varied from 0.45 d(-1) +/- 0.04 to 0.72 d(-1) +/- 0.2 respectively; the mean value of micro(max,AOB) in the MBR samples (always maintained at SRT = 20 d) was in the range 0.45-0.49 d(-1). The endogenous decay coefficients of the NOB and AOB and the maximum specific growth rates of the NOB were similar in both MBR and CASP. Inhibition tests with different concentrations of allylthiourea (ATU) were carried out on samples from both activated sludge systems: the MBR sludge exhibited higher sensitivity to a low ATU concentration; however, the maximum nitrification activity recovered more rapidly than the CASP sludge.
Collapse
Affiliation(s)
- G Munz
- Department of Civil and Environmental Engineering, University of Florence, Via S. Marta n.3, 50139 Florence, Italy.
| | | | | | | |
Collapse
|
38
|
Marzorati M, Verhelst A, Luta G, Sinnott R, Verstraete W, de Wiele TV, Possemiers S. In vitro modulation of the human gastrointestinal microbial community by plant-derived polysaccharide-rich dietary supplements. Int J Food Microbiol 2010; 139:168-76. [DOI: 10.1016/j.ijfoodmicro.2010.02.030] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Revised: 01/30/2010] [Accepted: 02/28/2010] [Indexed: 01/06/2023]
|