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Wei Z, Li D, Li S, Zeng H, Zhang J. Negative role of filamentous bulking and its elimination in anammox process. BIORESOURCE TECHNOLOGY 2024; 395:130336. [PMID: 38237642 DOI: 10.1016/j.biortech.2024.130336] [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: 12/07/2023] [Revised: 01/11/2024] [Accepted: 01/13/2024] [Indexed: 01/25/2024]
Abstract
In this study, the filamentous bulking (FB) with moderate and excessive levels were demonstrated to induce anammox failure by inhibiting nitrogen (N) removal and biomass retention. The low external mass transfer resulted from high liquid-surface friction and low turbulence of filamentous surface was considered the "trigger" of anammox failure, which decreased flux of nitrogen flow toward granular surface and directly limited N-removal loading, which meanwhile exposed granules with N-scarcity environment and indirectly inhibited N-removal bio-activity. Low bio-activity performed poor extracellular polymeric substances secretion further destroyed bio-aggregation with low suface hydrophobicity, which acted as "accelerator" for granule disintegration and biomass washout, ultimatly leading to anammox failure. Fortunately, incresing hydraulic shear stress could eradicate FB's negative effects without inhibiting FB itself, which promoted re-granulation and N-remval restore by enhancing external mass transfer more than hydraulic detachment. Enhancing mechanical stirring with FB level was necessary to maintain stable operation of granular anammox system.
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Affiliation(s)
- Ziqing Wei
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Dong Li
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China.
| | - Shuai Li
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Huiping Zeng
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Jie Zhang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
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2
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Pechaud Y, Derlon N, Queinnec I, Bessiere Y, Paul E. Modelling biofilm development: The importance of considering the link between EPS distribution, detachment mechanisms and physical properties. WATER RESEARCH 2024; 250:120985. [PMID: 38118257 DOI: 10.1016/j.watres.2023.120985] [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: 09/10/2023] [Revised: 12/02/2023] [Accepted: 12/06/2023] [Indexed: 12/22/2023]
Abstract
In industry, treatments against biofilms need to be optimized and, in the wastewater treatment field, biofilm composition needs to be controlled. Therefore, describing the biochemical and physical structures of biofilms is now required to better understand the influence of operating parameters and treatment on biofilms. The present study aims to investigate how growth conditions influence EPS composition, biofilm physical properties and volume detachment using a 1D biofilm model. Two types of EPS are considered in the present model, proteins and polysaccharides. The main hypotheses are that: (i) the production of polysaccharides occurs mainly under strong nutrient limitation(s) while the production of proteins is coupled to both the substrate uptake rate and the lysis process; (ii) the local biofilm porosity depends on the local biofilm composition. Both volume and surface detachment occur in biofilms and volume detachment extent depends on the biofilm local cohesion and thus on the local composition of biofilms for a given shear stress. The model is based on experimental trends and aims to represent these observations on the basis of biochemical and physical processes. Four case studies covering a wide range of contrasting growth conditions such as different COD/N ratios, applied SOLR and shear stresses are investigated. The model predicts how the biochemical and physical biofilm structures change as a result of contrasting growth conditions. More precisely simulation results are in good agreement with the main experimental observations reported in the literature, such as: (i) a strong nitrogen limitation of growth induces an important accumulation of polysaccharides leading to a more porous and homogenous biofilm, (ii) a high applied surface organic loading load allows to obtain a high biofilm thickness, (iii) a strong shear stress applied during the biofilm growth leads to a reduction of the biofilm thickness and to a consolidation of the biofilm structure. Overall, this model represents a relevant decision tool for the selection of appropriate enzymatic treatments in the context of negative biofilm control. From our results, it appears that protease based treatments should be more appropriate for biofilms developed under low COD/N ratios (about 20 gCOD/gN) whereas both glucosidases and proteases based treatments should be more appropriate for biofilms developed under high COD/N ratio (about 70 gCOD/gN). In addition, the model could be useful for other applications such as resource recovery in biofilms or granules, and help to better understand biological membrane fouling.
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Affiliation(s)
- Y Pechaud
- TBI, CNRS, INRAE, INSA, Université de Toulouse, 35 avenue de Rangueil, Toulouse 31077, France; Laboratoire Géomatériaux et Environnement (EA 4508), Université Gustave Eiffel, Marne-la-Vallée 77454, France.
| | - N Derlon
- EAWAG, Ueberlandstrasse 133, P.O Box 611, Dübendorf 8600, Switzerland
| | - I Queinnec
- CNRS, LAAS, 7 avenue du Colonel Roche, Toulouse F-31400, France
| | - Y Bessiere
- TBI, CNRS, INRAE, INSA, Université de Toulouse, 35 avenue de Rangueil, Toulouse 31077, France
| | - E Paul
- TBI, CNRS, INRAE, INSA, Université de Toulouse, 35 avenue de Rangueil, Toulouse 31077, France.
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3
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Snyder ED, Tank JL, Brandão-Dias PFP, Bibby K, Shogren AJ, Bivins AW, Peters B, Curtis EM, Bolster D, Egan SP, Lamberti GA. Environmental DNA (eDNA) removal rates in streams differ by particle size under varying substrate and light conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166469. [PMID: 37633388 DOI: 10.1016/j.scitotenv.2023.166469] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 08/17/2023] [Accepted: 08/19/2023] [Indexed: 08/28/2023]
Abstract
The use of environmental DNA (eDNA) as a sampling tool offers insights into the detection of invasive and/or rare aquatic species and enables biodiversity assessment without traditional sampling approaches, which are often labor-intensive. However, our understanding of the environmental factors that impact eDNA removal (i.e., how rapidly eDNA is removed from the water column by the combination of decay and physical removal) in flowing waters is limited. This limitation constrains predictions about the location and density of target organisms after positive detection. To address this question, we spiked Common Carp (Cyprinus carpio) eDNA into recirculating mesocosms (n = 24) under varying light (shaded versus open) and benthic substrate conditions (no substrate, bare substrate, and biofilm-colonized substrate). We then collected water samples from each mesocosm at four time points (40 min, 6 h, 18 h, and 48 h), and sequentially filtered the samples through 10, 1.0, and 0.2 μm filters to quantify removal rates for different eDNA particle sizes under varying light and substrate conditions. Combining all size classes, total eDNA removal rates were higher for mesocosms with biofilm-colonized substrate compared to those with no substrate or bare (i.e., no biofilm) substrate, which is consistent with previous findings linking biofilm colonization with increased eDNA removal and degradation. Additionally, when biofilm was present, light availability increased eDNA removal; eDNA levels fell below detection after 6-18 h for open mesocosms versus 18-48 h for shaded mesocosms. Among size classes, larger particles (>10 μm) were removed faster than small particles (1.0-0.2 μm). These results suggest that changes in the distribution of eDNA size classes over time (e.g., with downstream transport) and with differing environmental conditions could be used to predict the location of target organisms in flowing waters, which will advance the use of eDNA as a tool for species monitoring and management.
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Affiliation(s)
- Elise D Snyder
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences, Notre Dame, IN 46556, USA.
| | - Jennifer L Tank
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences, Notre Dame, IN 46556, USA.
| | | | - Kyle Bibby
- Department of Civil & Environmental Engineering & Earth Science, University of Notre Dame, 156 Fitzpatrick Hall of Engineering, Notre Dame, IN 46556, USA.
| | - Arial J Shogren
- Department of Biological Sciences, The University of Alabama, Science and Engineering Complex,1325 Hackberry Ln, Tuscaloosa, AL 35401, USA.
| | - Aaron W Bivins
- Department of Civil and Environmental Engineering, Louisiana State University, 3255 Patrick F. Taylor Hall, Baton Rouge, LA 70803, USA.
| | - Brett Peters
- Environmental Change Initiative, University of Notre Dame, 721 Flanner Hall, Notre Dame, IN 46556, USA.
| | - Erik M Curtis
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences, Notre Dame, IN 46556, USA.
| | - Diogo Bolster
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences, Notre Dame, IN 46556, USA; Department of Civil & Environmental Engineering & Earth Science, University of Notre Dame, 156 Fitzpatrick Hall of Engineering, Notre Dame, IN 46556, USA.
| | - Scott P Egan
- Department of BioSciences, Rice University, 6100 Main St, Houston, TX 77005-1827, USA.
| | - Gary A Lamberti
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences, Notre Dame, IN 46556, USA.
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Chen X, Zhao Q, Yang L, Wei W, Ni BJ, Chen X. Impacts of granular sludge properties on the bioreactor performing nitrate/nitrite-dependent anaerobic methane oxidation/anammox processes. BIORESOURCE TECHNOLOGY 2023; 386:129510. [PMID: 37495161 DOI: 10.1016/j.biortech.2023.129510] [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: 06/16/2023] [Revised: 07/14/2023] [Accepted: 07/16/2023] [Indexed: 07/28/2023]
Abstract
In this work, a bioprocess model was applied to first determine the impacts of influent substrates conditions on the granular bioreactor performing nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) and anammox integrated processes and then investigate the roles of granular sludge properties in regulating the bioreactor performance and start-up process. The ideal influent substrates conditions were identified at NO2--N/NH4+-N of 1:1 and dissolved CH4 concentration of 85 g COD m-3, which achieved 98.6% total nitrogen removal and 87.7% dissolved CH4 utilization. Under such ideal influent conditions, the initial properties of granular sludge didn't significantly affect the granular bioreactor performance. However, inoculation of granular sludge with a relatively small granular sludge size and a high abundance of n-DAMO archaea or/and anammox bacteria could effectively shorten the bioreactor start-up. Meanwhile, reducing the diffusivity of solutes within granular sludge was also beneficial for expediting the start-up process and promoting dissolved CH4 utilization.
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Affiliation(s)
- Xinyan Chen
- Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Safety Engineering, Fuzhou University, Fuzhou 350116, China
| | - Qi Zhao
- Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Safety Engineering, Fuzhou University, Fuzhou 350116, China
| | - Linyan Yang
- School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Wei Wei
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Bing-Jie Ni
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Xueming Chen
- Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Safety Engineering, Fuzhou University, Fuzhou 350116, China.
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Li M, Perez-Calleja P, Kim B, Picioreanu C, Nerenberg R. Unique stratification of biofilm density in heterotrophic membrane-aerated biofilms: An experimental and modeling study. CHEMOSPHERE 2023; 327:138501. [PMID: 36963576 DOI: 10.1016/j.chemosphere.2023.138501] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 06/18/2023]
Abstract
We consistently find a band of high cell density develop within heterotrophic membrane-aerated biofilms. This study reports and attempts to explain this unique behavior. Biofilm density affects volumetric reaction rates, biofilm growth rates, substrate diffusion, and mechanical behavior. Yet the mechanisms and dynamics of biofilm density development are poorly understood. In this study, a membrane-aerated biofilm, where O2 was supplied from the base of the biofilm and acetate from the bulk liquid, was used to explore spatial and temporal patterns of density development. Biofilm density was assessed by optical coherence tomography. After inoculation, the biofilm quickly increased in thickness, with a low density throughout. However, as the biofilm reached a stable thickness of around 1000 μm, a high-density layer developed in the biofilm interior. The layer slowly expanded over time. Oxygen microprofiles in the biofilm showed this layer coincided with the most metabolically active zone, resulting from counter-diffusing O2 and acetate. The formation of this dense layer appeared to be related to changes in growth rates. Initially, high growth rates throughout the biofilm presumably led to fast-growing, low-density biofilms. As the biofilm became thicker, and as substrates became limiting in the biofilm interior, growth rates decreased, resulting in new growth at a higher density. A 1-D mathematical model with variable biofilm density was developed by linking the rates of extracellular polymeric substances (EPS) production to the growth rate. The model captured the initial fast growth at a low density, followed by a slower, substrate-limited growth in the biofilm interior, producing a dense band within the biofilm. Together, these results suggest that low growth rates can lead to high-density zones within the interior of counter-diffusional biofilms. These findings should also be relevant to conventional, co-diffusional biofilms, although differences in density may be less obvious.
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Affiliation(s)
- Mengfei Li
- University of Notre Dame, Department of Civil and Environmental Engineering and Earth Sciences, 156 Fitzpatrick Hall, Notre Dame, IN, 46556, USA; Jacobs Engineering Group, Bingham Farms, MI, 48025, USA.
| | - Patricia Perez-Calleja
- University of Notre Dame, Department of Civil and Environmental Engineering and Earth Sciences, 156 Fitzpatrick Hall, Notre Dame, IN, 46556, USA.
| | - Bumkyu Kim
- University of Notre Dame, Department of Civil and Environmental Engineering and Earth Sciences, 156 Fitzpatrick Hall, Notre Dame, IN, 46556, USA.
| | - Cristian Picioreanu
- Division of Biological and Environmental Sciences and Engineering (BESE), Water Desalination and Reuse Center (WDRC), Environmental Science and Engineering Program, King Abdullah University of Science and Technology, Thuwal, 23955, Saudi Arabia.
| | - Robert Nerenberg
- University of Notre Dame, Department of Civil and Environmental Engineering and Earth Sciences, 156 Fitzpatrick Hall, Notre Dame, IN, 46556, USA.
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Li D, Wei Z, Li S, Zeng H, Zhang J. Insight into dead space effects in granular anammox process with organic stress. BIORESOURCE TECHNOLOGY 2022; 359:127504. [PMID: 35738318 DOI: 10.1016/j.biortech.2022.127504] [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: 05/14/2022] [Revised: 06/16/2022] [Accepted: 06/17/2022] [Indexed: 06/15/2023]
Abstract
In this study, the dead space was demonstrated to enhance the robustness of anammox nitrogen (N)-removal under organic stress. Different from the "yellow aggregates" that inhabit in mixing space were assembled by anammox and heterotrophic micro-colonies, the "red granules" that inhabit in dead space were formed by initial anammox aggregates that growing outward with higher anammox-activity, settleability and sludge stability, which endowed the dead space the role of "anammox-stabilizer" with prominent anammox N-removal contribution (63.8%) especially under high organic stress. The extracellular polymeric substances (EPS) dynamic balance test revealed that the high and stable EPS contents in dead space were attributed to the low EPS degradation rate and low proportion of heterotrophic bacteria (HB)-produced EPS, respectively. The weak hydrodynamic forces were the key to less HB-colonization and high granular stability in dead space. Retaining a certain dead space is necessary to prevent anammox bacteria (AnAOB) loss under organic stress.
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Affiliation(s)
- Dong Li
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China.
| | - Ziqing Wei
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Shuai Li
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Huiping Zeng
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Jie Zhang
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
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Chen Y, Qin H, Lu Y, Liu H, Zhang J. A novel method to measure air-immobile regions of the composting pile by inverse calculation combined with gas tracer test. WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 150:131-140. [PMID: 35830767 DOI: 10.1016/j.wasman.2022.06.036] [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: 04/11/2022] [Revised: 06/27/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
Air-immobile regions in composting piles obstruct O2 mass transport and exacerbate the formation and emission of harmful off-gases. However, effective methods for measuring the parameters of these air-immobile regions are lacking. With quartz sand piles, this study first adjusted the circumstances of a gas tracer test (gas tracer, its injection volume, and chamber type) using the two-region model (TRM). The effects of β (proportional coefficient of gas in the air-mobile region) and ω (mass exchange coefficient) on the breakthrough curves (BTCs) of the gases were then explored. Finally, an inverse calculation method was used to measure the feature parameters of air-immobile regions in two composting piles (temperature-increasing and thermophilic phases) and estimate the O2 concentrations in different composting piles (50, 100, 200 cm whole height; layers of 50, 100, 200 cm height in a 200-cm high pile). The results showed that the optimal conditions were achieved when 100 mL helium (He) as the gas tracer and a cylinder with a height/diameter ratio of 3 as the chamber were used. With the simulating composting piles, increasing β or ω slowed breakthrough and decreased peak concentration in BTCs of a gas tracer. Tracer-inverse calculation protocol can be used to efficiently estimate the volume ratios of air-immobile regions (φ) and first-order mass transfer coefficient (α), with the values of 39%/46% and 0.001/0.006 min-1 in the composting piles during temperature-increasing /thermophilic phase. The TRM also predicted the O2 concentration in the off-gas or air-mobile/immobile regions of the temperature-increasing-phase composting piles.
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Affiliation(s)
- Yixiao Chen
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China
| | - Haiguang Qin
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China
| | - Yulan Lu
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China
| | - Hongtao Liu
- Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
| | - Jun Zhang
- Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin University of Technology, Guilin 541004, China.
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Modeling the Succinic Acid Bioprocess: A Review. FERMENTATION 2022. [DOI: 10.3390/fermentation8080368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Succinic acid has attracted much interest as a key platform chemical that can be obtained in high titers from biomass through sustainable fermentation processes, thus boosting the bioeconomy as a critical production strategy for the future. After several years of development of the production of succinic acid, many studies on lab or pilot scale production have been reported. The relevant experimental data reveal underlying physical and chemical dynamic phenomena. To take advantage of this vast, but disperse, kinetic information, a number of mathematical kinetic models of the unstructured non-segregated type have been proposed in the first place. These relatively simple models feature critical aspects of interest for the design, control, optimization and operation of this key bioprocess. This review includes a detailed description of the phenomena involved in the bioprocesses and how they reflect on the most important and recent models based on macroscopic and metabolic chemical kinetics, and in some cases even coupling mass transport.
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Yang X, He Q, Liu T, Zheng F, Mei H, Chen M, Liu G, Vymazal J, Chen Y. Impact of microplastics on the treatment performance of constructed wetlands: Based on substrate characteristics and microbial activities. WATER RESEARCH 2022; 217:118430. [PMID: 35429885 DOI: 10.1016/j.watres.2022.118430] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 04/04/2022] [Accepted: 04/06/2022] [Indexed: 06/14/2023]
Abstract
Presence of microplastics (MPs) in wastewater has posed a huge ecosystem risk. Constructed wetlands (CWs) can effectively intercept MPs, while with MPs accumulation the response of CWs' performance is still unclear. In order to evaluate those effects, we conducted a 370-day experiment using CW microcosms fed with different levels (0, 10, 100, and 1000 μg/L) of polystyrene (PS) MPs (diameter: 50-100 μm). Results showed that nitrogen removal efficiency was increased (by 3.9%-24.7%) during the first 60 days and then decreased (by 7.1%-41.3%) with MPs accumulating, but no obvious change in COD and TP removal was observed. From further analysis, MPs accumulation changed the biofilm composition (TOC content increased from 41.4% to 52.7%), substrate porosity (electrical resistivity increased by 1.2-2.4 folds), and oxygen mass transfer (|KLa,O2| increased from 3.5% to 18.6%). Moreover, the microbial dynamics presented a higher abundance of nitrifiers (Nitrospira and Nitrosomonas) during the 60-day experiment and a lower abundance in the last days, while denitrifiers (Thauera, Thiobacillus, and Anaerolinea) had a high relative abundance throughout the experiment, being consistent with the variation of nitrification and denitrification rates. Finally, structural equation model analysis proved that due to the changes of substrate characteristics and microbial compositions and activities, the obvious decrease in nitrification efficiency was a direct reason for the decline of nitrogen removal during 370-day MPs accumulation. Overall, our study first prove that MPs accumulation can cause a series of changes in physicochemical and microbial characteristics of substrate, and ultimately affect the nitrogen-transforming process in CWs. Although our conclusions were based on the lab-scale CWs being different from the real wetlands, we hope that the conclusions can provide the effective regulatory strategies to guide the control of MPs in the actual wetlands.
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Affiliation(s)
- Xiangyu Yang
- Key Laboratory of the Three Gorges Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Campus B 83 Shabeijie, Shapingba, Chongqing 400044, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, China; State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qiang He
- Key Laboratory of the Three Gorges Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Campus B 83 Shabeijie, Shapingba, Chongqing 400044, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, China
| | - Tao Liu
- Key Laboratory of the Three Gorges Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Campus B 83 Shabeijie, Shapingba, Chongqing 400044, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, China
| | - Feifei Zheng
- Key Laboratory of the Three Gorges Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Campus B 83 Shabeijie, Shapingba, Chongqing 400044, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, China
| | - Han Mei
- Key Laboratory of the Three Gorges Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Campus B 83 Shabeijie, Shapingba, Chongqing 400044, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, China
| | - Mengli Chen
- Key Laboratory of the Three Gorges Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Campus B 83 Shabeijie, Shapingba, Chongqing 400044, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, China
| | - Gang Liu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jan Vymazal
- Department of Applied Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague,16521, Prague 6, Czech Republic
| | - Yi Chen
- Key Laboratory of the Three Gorges Region's Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Campus B 83 Shabeijie, Shapingba, Chongqing 400044, China; National Centre for International Research of Low-carbon and Green Buildings, Chongqing University, Chongqing, 400044, China.
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The role of shear dynamics in biofilm formation. NPJ Biofilms Microbiomes 2022; 8:33. [PMID: 35487949 PMCID: PMC9055050 DOI: 10.1038/s41522-022-00300-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 04/04/2022] [Indexed: 11/08/2022] Open
Abstract
There is growing evidence that individual bacteria sense and respond to changes in mechanical loading. However, the subtle responses of multispecies biofilms to dynamic fluid shear stress are not well documented because experiments often fail to disentangle any beneficial effects of shear stress from those delivered by convective transport of vital nutrients. We observed the development of biofilms with lognormally distributed microcolony sizes in drinking water on the walls of flow channels underflow regimes of increasing complexity. First, where regular vortices induced oscillating wall shear and simultaneously enhanced mass transport, which produced the thickest most extensive biofilms. Second, where unsteady uniform flow imposed an oscillating wall shear, with no enhanced transport, and where the biomass and coverage were only 20% smaller. Finally, for uniform steady flows with constant wall shear where the extent, thickness, and density of the biofilms were on average 60% smaller. Thus, the dynamics of shear stress played a significant role in promoting biofilm development, over and above its magnitude or mass transfer effects, and therefore, mechanosensing may prevail in complex multispecies biofilms which could open up new ways of controlling biofilm structure.
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11
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Qi L, Liang R, Jiang T, Qin W. Anti-fouling polymeric membrane ion-selective electrodes. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2022.116572] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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12
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Kubannek F, Block J, Munirathinam B, Krull R. Reaction kinetics of anodic biofilms under changing substrate concentrations: Uncovering shifts in Nernst‐Monod curves via substrate pulses. Eng Life Sci 2022; 22:152-164. [PMID: 35382544 PMCID: PMC8961052 DOI: 10.1002/elsc.202100088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 11/14/2021] [Accepted: 12/19/2021] [Indexed: 11/25/2022] Open
Abstract
In the present study, it is shown that the concentration dependency of undefined mixed culture anodic biofilms does not follow a single kinetic curve, such as the Nernst‐Monod curve. The biofilms adapt to concentration changes, which inevitably have to be applied to record kinetic curves, resulting in strong shifts of the kinetic parameters. The substrate concentration in a continuously operated bioelectrochemical system was changed rapidly via acetate pulses to record Nernst‐Monod curves which are not influenced by biofilm adaptation processes. The values of the maximum current density jmax and apparent half‐saturation rate constant Ks increased from 0.5 to 1 mA cm−2 and from 0.5 to 1.6 mmol L−1, respectively, within approximately 5 h. Double pulse experiments with a starvation phase between the two acetate pulses showed that jmax and Ks decrease reversibly through an adaptation process when no acetate is available. Pseudo‐capacitive charge values estimated from non‐turnover cyclic voltammograms (CV) led to the hypothesis that biofilm adaptation and the observed shift of the Nernst‐Monod curves occurred due to changes in the concentration of active redox proteins in the biofilm. It is argued that concentration‐related parameters of kinetic models for electroactive biofilms are only valid for the operating points where they have been determined and should always be reported with those conditions.
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Affiliation(s)
- Fabian Kubannek
- Institute of Energy and Process Systems Engineering Technische Universität Braunschweig Braunschweig Germany
| | - Jonathan Block
- Institute of Biochemical Engineering Technische Universität Braunschweig Braunschweig Germany
| | - Balakrishnan Munirathinam
- Institute of Energy and Process Systems Engineering Technische Universität Braunschweig Braunschweig Germany
| | - Rainer Krull
- Institute of Biochemical Engineering Technische Universität Braunschweig Braunschweig Germany
- Center of Pharmaceutical Engineering (PVZ) Technische Universität Braunschweig Braunschweig Germany
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13
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Chen Q, Zhang X, Xie Q, Lee YH, Lee JS, Shi H. Microplastics habituated with biofilm change decabrominated diphenyl ether degradation products and thyroid endocrine toxicity. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 228:112991. [PMID: 34798360 DOI: 10.1016/j.ecoenv.2021.112991] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 11/02/2021] [Accepted: 11/11/2021] [Indexed: 06/13/2023]
Abstract
Microplastics (MPs) are rapidly colonized by microbial biofilms in a natural aquatic environment, and the nature of the microbial community and type of MP can result in different degradation products of organic pollutants. Here, we quantified the degradation products of a ubiquitously detected pollutant, decabrominated diphenyl ether (BDE-209), under both light-only and biota conditions and in the absence or presence of three kinds of MPs, styrofoam polystyrene, hard polyamide, and polypropylene film. The results showed that the BDE-209 concentration increased by 0.7-2.8 fold in the presence of MPs, probably due to the "sustained release" desorption effect. Under light-only conditions, the penta- and hexa-BDE concentrations in the presence of styrofoam or hard MPs were significantly reduced, which can be deemed a beneficial effect. However, when biota were present, the debromination products increased with the addition of MPs, particularly in the presence of styrofoam MPs. These products caused a 1.7-fold upregulation in triiodothyronine content and a 5.9-fold upregulation of thyroid stimulating hormone β expression in zebrafish larvae. The increase in debromination products could be attributed to the distinct high abundance of the bacteria Chloroflexi, Proteobacteria, and Basidiomycotina on styrofoam MPs that can participate in pollutant degradation. Collectively, our results indicate that MPs can alter the degradation pathways of BDE-209 and increase the toxicity to the endocrine system and the thyroid in aquatic organisms.
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Affiliation(s)
- Qiqing Chen
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200241, China
| | - Xiyang Zhang
- School of Marine Sciences, Zhuhai Key Laboratory of Marine Bioresources and Environment, Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Sun Yat-Sen University, Zhuhai 519000, China
| | - Qiang Xie
- School of Marine Sciences, Zhuhai Key Laboratory of Marine Bioresources and Environment, Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, Sun Yat-Sen University, Zhuhai 519000, China
| | - Young Hwan Lee
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Jae-Seong Lee
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Huahong Shi
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200241, China.
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14
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Lin W, Zhang Y, Li D, Wang XM, Huang X. Roles and performance enhancement of feed spacer in spiral wound membrane modules for water treatment: A 20-year review on research evolvement. WATER RESEARCH 2021; 198:117146. [PMID: 33945947 DOI: 10.1016/j.watres.2021.117146] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/07/2021] [Accepted: 04/11/2021] [Indexed: 06/12/2023]
Abstract
Membrane technologies have been widely applied in water treatment, wastewater reclamation and seawater desalination. Feed spacer present in spiral wound membrane (SWM) modules plays a pivotal role in creating flow channels, promoting fluid mixing and enhancing mass transfer. However, it induces the increase of feed channel pressure (FCP) drop and localized stagnant zones that provokes membrane fouling. For the first time, we comprehensively review the research evolvement on feed spacer in SWM modules for water treatment over the last 20 years, to reveal the impacts of feed spacer on the hydrodynamics and biofouling in the spacer-filled channel, and to discuss the potential approaches and current limitations for the modification of feed spacer. The research process can be divided into three phases, with research focus shifting from hydrodynamics in Phase Ⅰ (the year of 2001-2008), to biofouling in Phase Ⅱ (the year of 2009-2015), and then to novel spacer designs in Phase Ⅲ (the year of 2016-2020). The spacer configuration has a momentous impact on the hydraulic performance regarding flow velocity field, shear stress, mass transfer and FCP drop. Biofouling initially occurs on feed spacer, especially around spacer filaments and the contact zones with membrane surface, and ultimately degrades the overall membrane performance indicating the importance of controlling spacer biofouling. The modification of feed spacer is mainly achieved by altering surface chemistry or introducing novel configurations. However, the stability of spacer coating and the economy and practicality of 3D-printed spacer remain a predicament to be tackled. Future studies are suggested to focus on the standardization of testing conditions for spacer evaluation, the effect of hydrodynamics on membrane fouling control, the design and fabrication of novel feed spacer adaptable for SWM modules, the application of feed spacer for drinking water production, organic fouling control in spacer-filled channel and the role of permeate spacer on membrane performance.
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Affiliation(s)
- Weichen Lin
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China
| | - Yuting Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China
| | - Danyang Li
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China
| | - Xiao-Mao Wang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China; Research and Application Center for Membrane Technology, School of Environment, Tsinghua University, Beijing 100084, China.
| | - Xia Huang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China; Research and Application Center for Membrane Technology, School of Environment, Tsinghua University, Beijing 100084, China.
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15
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Chodorski J, Hauth J, Strieth D, Wirsen A, Ulber R. Diffusion profiles in L. lactis biofilms under different conditions. Eng Life Sci 2021; 21:29-36. [PMID: 33531888 PMCID: PMC7837298 DOI: 10.1002/elsc.202000059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 10/23/2020] [Indexed: 01/26/2023] Open
Abstract
Despite being an important topic in biofilm research, we still know little about diffusion in biofilms. Emerging biofilms of Lactococcus lactis growing in custom-made flow-cells were monitored and diffusion constants across the height of the biofilms recorded. The biofilms showed different diffusional behavior with regard to flow rate and pH variations, despite growing to similar thickness. At a higher flow rate, the biofilm exhibits slower diffusion compared to the reference cultivation at lower flow rate. By increasing pH, the biofilm exhibited fast growth and little difference in diffusion compared to the reference cultivation. Furthermore, the diffusion inside of the biofilms differed depending on the position in the flow-cell. The present study reveals new insights in how external factors can affect structure and density of biofilms. The method can be reliably used for L. lactis biofilms with a thickness up to 120 μm.
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Affiliation(s)
- Jonas Chodorski
- Institute of Bioprocess Engineering, Department of Mechanical and Process EngineeringTU KaiserslauternKaiserslauternGermany
| | - Jan Hauth
- Fraunhofer ITWMKaiserslauternGermany
| | - Dorina Strieth
- Institute of Bioprocess Engineering, Department of Mechanical and Process EngineeringTU KaiserslauternKaiserslauternGermany
| | | | - Roland Ulber
- Institute of Bioprocess Engineering, Department of Mechanical and Process EngineeringTU KaiserslauternKaiserslauternGermany
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16
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Rizk N, Ait-Mouheb N, Molle B, Roche N. Treated wastewater reuse in micro-irrigation: effect of shear stress on biofilm development kinetics and chemical precipitation. ENVIRONMENTAL TECHNOLOGY 2021; 42:206-216. [PMID: 31145040 DOI: 10.1080/09593330.2019.1625956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 05/17/2019] [Indexed: 06/09/2023]
Abstract
Treated wastewater in micro-irrigation is a promising approach that could be used to decrease the pressure on good quality water resources. However, the clogging of such systems due to biofilm development and chemical precipitation constitute a constraint with the use of treated wastewater (TWW) and lead to lower irrigation system performance. The objective of this work is to study the development of biofilm and composition of fouling due to TWW under shear stresses of 0.7, 2.2 and 4.4 Pa detected along micro-irrigation systems. For this purpose, a Taylor-Couette reactor (TCR) was specifically calibrated for the cultivation of biofilm. The analysis of fouling composition samples (organic and inorganic) shows that biofilm tends to develop under the highest shear stress value (4.4 Pa). Precipitation of calcium carbonate in the form of calcite was observed in conjunction with biofilm growth using X-ray diffractometry (XRD) and thermogravimetric analysis (TGA). These results can be used to ascertain the origins of chemical and biological clogging of drippers and fouling of pipes related to reclaimed water- irrigation.
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Affiliation(s)
- Nancy Rizk
- IRSTEA Montpellier, Université de Montpellier, Montpellier, France
- Aix Marseille University, Aix-en-Provence, France
| | | | - Bruno Molle
- IRSTEA Montpellier, Université de Montpellier, Montpellier, France
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17
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You G, Wang C, Wang P, Hou J, Xu Y, Miao L, Feng T. Insights into spatial effects of ceria nanoparticles on oxygen mass transfer in wastewater biofilms: Interfacial microstructure, in-situ microbial activity and metabolism regulation mechanism. WATER RESEARCH 2020; 176:115731. [PMID: 32251943 DOI: 10.1016/j.watres.2020.115731] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 03/13/2020] [Accepted: 03/16/2020] [Indexed: 06/11/2023]
Abstract
Growing international exploitation of ceria nanoparticles (CeO2 NPs) for varied applications has increased their release into wastewater treatment plants. Mass transfer of oxygen (MTO) in wastewater biofilm is of considerable importance to influence the activity and purification ability of biofilm. Herein, we investigated the spatial distribution of oxygen in gas-liquid-biofilm phases, the microstructure of interfaces and the in-situ microbial activity to reveal the impacts of CeO2 NPs on MTO in wastewater biofilm and the related mechanisms. After exposure to 1 and 10 mg/L CeO2 NPs, the oxygen transfer coefficient (KLa) from gas to wastewater increased by 28.1% and 75.3% with a reduction of thickness in gas-liquid boundary layer, indicating the enhanced MTO in gas-liquid interface. In contrast, the MTO in liquid-biofilm interface was negatively affected and the thickness of liquid-biofilms boundary layer significantly increased, which was mainly attributed to the smoother surface and the decreased surface area difference of biofilm. Within biofilm, the microbial activity was inhibited by 10 mg/L CeO2 NPs, whereas the production of extracellular polymeric substance (EPS) was significantly improved, leading to a decline of 35.0% in the internal effective diffusivity (DB) and a 300-μm reduction of oxygen penetration depth. Moreover, the relative activities of key enzymes involved in glycometabolism indicated the transition of Embden-Meyerhof pathway to pentose phosphate pathway, which probably contributed to the enhanced EPS production and consequently increased mass transfer resistance in liquid-biofilm interface and inner biofilm. These results could potentially expand the knowledge on mass transfer of nutrients or pollutants in wastewater biofilm in response to NPs exposure.
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Affiliation(s)
- Guoxiang You
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China
| | - Chao Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China
| | - Peifang Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China.
| | - Jun Hou
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China.
| | - Yi Xu
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China
| | - Lingzhan Miao
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China
| | - Tao Feng
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China
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18
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Recupido F, Toscano G, Tatè R, Petala M, Caserta S, Karapantsios TD, Guido S. The role of flow in bacterial biofilm morphology and wetting properties. Colloids Surf B Biointerfaces 2020; 192:111047. [PMID: 32388030 DOI: 10.1016/j.colsurfb.2020.111047] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 03/26/2020] [Accepted: 04/11/2020] [Indexed: 02/06/2023]
Abstract
Biofilms are bacterial communities embedded in an extracellular matrix, able to adhere to surfaces. Different experimental set-ups are widely used for in vitro biofilm cultivation; however, a well-defined comparison among different culture conditions, especially suited to interfacial characterization, is still lacking in the literature. The main objective of this work is to study the role of flow on biofilm formation, morphology and interfacial properties. Three different in vitro setups, corresponding to stagnant, shaking, and laminar flow conditions (custom-made flow cell), are used in this work to grow single strain biofilms of Pseudomonas fluorescens AR 11 on glass coupons. Results show that flow conditions significantly influenced biofilm formation kinetics, affecting mass transfer and cell attachment/detachment processes. Distinct morphological patterns are found under different flow regimes. Static contact angle data do not depend significantly on biofilm growth conditions in the parametric range investigated in this work.
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Affiliation(s)
- Federica Recupido
- Division of Chemical Technology, School of Chemistry, Aristotle University of Thessaloniki, University Box 116, 54124, Thessaloniki, Greece; Department of Chemical, Materials and Industrial Production Engineering (DICMaPI), University of Naples, Federico II, Piazzale V. Tecchio 80, 80125, Naples, Italy
| | - Giuseppe Toscano
- Department of Chemical, Materials and Industrial Production Engineering (DICMaPI), University of Naples, Federico II, Piazzale V. Tecchio 80, 80125, Naples, Italy
| | - Rosarita Tatè
- Institute of Genetics and Biophysics: "A. Buzzati-Traverso" (IGB-CNR), Pietro Castellino 111, 80131, Naples, Italy
| | - Maria Petala
- Department of Civil Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Sergio Caserta
- Department of Chemical, Materials and Industrial Production Engineering (DICMaPI), University of Naples, Federico II, Piazzale V. Tecchio 80, 80125, Naples, Italy; CEINGE, Advanced Biotechnologies, 80145, Naples, Italy.
| | - Thodoris D Karapantsios
- Division of Chemical Technology, School of Chemistry, Aristotle University of Thessaloniki, University Box 116, 54124, Thessaloniki, Greece.
| | - Stefano Guido
- Department of Chemical, Materials and Industrial Production Engineering (DICMaPI), University of Naples, Federico II, Piazzale V. Tecchio 80, 80125, Naples, Italy; CEINGE, Advanced Biotechnologies, 80145, Naples, Italy
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19
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Chen F, Li ZL, Lv M, Huang C, Liang B, Yuan Y, Lin XQ, Gao XY, Wang AJ. Recirculation ratio regulates denitrifying sulfide removal and elemental sulfur recovery by altering sludge characteristics and microbial community composition in an EGSB reactor. ENVIRONMENTAL RESEARCH 2020; 181:108905. [PMID: 31767354 DOI: 10.1016/j.envres.2019.108905] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 11/07/2019] [Accepted: 11/07/2019] [Indexed: 06/10/2023]
Abstract
Expanded granular sludge blanket (EGSB) is regarded as a promising reactor to carry out denitrifying sulfide removal (DSR) and elemental sulfur (S0) recovery. Although the recirculation ratio is an essential parameter for EGSB reactors, how it impacts the DSR process remains poorly understood. Here, three lab-scale DSR-EGSB reactors were established with the different recirculation ratios (3:1, 6:1 and 9:1) to evaluate the corresponding variations in pollutant removal, S0 recovery, anaerobic granular sludge (AGS) characteristics and microbial community composition. It was found that an intermediate recirculation ratio (6:1) could facilitate long-term reactor stability. Adequate recirculation ratio could enhance S0 recovery, but an excessive recirculation ratio (9:1) was likely to cause AGS fragmentation and biomass loss. The S0 desorbed more from sludge at higher recirculation ratios, probably due to the enhanced hydraulic disturbance caused by the increased recirculation ratios. At the low recirculation ratio (3:1), S0 accumulation as inorganic suspended solids in AGS led to a decrease in VSS/TSS ratio and mass transfer efficiency. Although typical denitrifying and sulfide-oxidizing bacteria (e.g., Azoarcus, Thauera and Arcobacter) were predominant in all conditions, facultative and heterotrophic functional bacteria (e.g., Azoarcus and Thauera) were more adaptable to higher recirculation ratios than autotrophs (e.g., Arcobacter, Thiobacillus and Vulcanibacillus), which was conducive to the formation of bacterial aggregates to response to the increased recirculation ratio. The study revealed recirculation ratio regulation significantly impacted the DSR-EGSB reactor performance by altering AGS characteristics and microbial community composition, which provides a novel strategy to improve DSR performance and S0 recovery.
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Affiliation(s)
- Fan Chen
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Zhi-Ling Li
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Miao Lv
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Cong Huang
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Bin Liang
- Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Ye Yuan
- Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng, 224051, China
| | - Xiao-Qiu Lin
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Xiang-Yu Gao
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Ai-Jie Wang
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
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20
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Soliman MYM, van Halem D, Medema G. Virus removal by ceramic pot filter disks: Effect of biofilm growth and surface cleaning. Int J Hyg Environ Health 2020; 224:113438. [PMID: 31978734 DOI: 10.1016/j.ijheh.2019.113438] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 12/14/2019] [Accepted: 12/17/2019] [Indexed: 10/25/2022]
Abstract
Ceramic pot filters are household water treatment and safe storage (HWTS) systems designed to improve the microbial quality of drinking water. They yield high log reduction values (LRVs) for bacterial and protozoan pathogens but provide very little removal of viruses. This study investigated virus removal of ceramic filter discs (CFDs), using feed water with 3 different nutrient levels under extended continuous operation and limited cleaning frequency. The results show that filter use without cleaning resulted in biofilm growth and MS2 LRV values increased with increasing feed water nutrient content. Cleaning the filter surface by scrubbing led to a partial or total loss in improved LRVs, indicating the importance of this biological top layer to the removal of MS2. Overall, the removal capacity of a matured biofilm remained constant, regardless of its age. MS2 LRVs ranged between 0.9 ± 0.2 LRV for low nutrient (LN), 1.6 ± 0.2 LRV for medium nutrient (MN) and 2.4 ± 0.5 LRV for high nutrient (HN) biofilms. Interestingly, a change in feed conditions for the HN filters resulted in an unprecedented high LRV of >4 LRV, which supports further investigation of the mechanistic role of biofilms in virus removal.
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Affiliation(s)
- Mona Y M Soliman
- Delft University of Technology, Department of Water Management, Stevinweg 1, 2628 CN, Delft, the Netherlands.
| | - Doris van Halem
- Delft University of Technology, Department of Water Management, Stevinweg 1, 2628 CN, Delft, the Netherlands.
| | - Gertjan Medema
- Delft University of Technology, Department of Water Management, Stevinweg 1, 2628 CN, Delft, the Netherlands; KWR Watercycle Research Institute, P.O. Box 1072, 3430 BB, Nieuwegein, the Netherlands.
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21
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A Minimally Invasive Microsensor Specially Designed for Simultaneous Dissolved Oxygen and pH Biofilm Profiling. SENSORS 2019; 19:s19214747. [PMID: 31683828 PMCID: PMC6864660 DOI: 10.3390/s19214747] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 10/18/2019] [Accepted: 10/30/2019] [Indexed: 02/07/2023]
Abstract
A novel sensing device for simultaneous dissolved oxygen (DO) and pH monitoring specially designed for biofilm profiling is presented in this work. This device enabled the recording of instantaneous DO and pH dynamic profiles within biofilms, improving the tools available for the study and the characterization of biological systems. The microsensor consisted of two parallel arrays of microelectrodes. Microelectrodes used for DO sensing were bare gold electrodes, while microelectrodes used for pH sensing were platinum-based electrodes modified using electrodeposited iridium oxide. The device was fabricated with a polyimide (Kapton®) film of 127 µm as a substrate for minimizing the damage caused on the biofilm structure during its insertion. The electrodes were covered with a Nafion® layer to increase sensor stability and repeatability and to avoid electrode surface fouling. DO microelectrodes showed a linear response in the range 0–8 mg L−1, a detection limit of 0.05 mg L−1, and a sensitivity of 2.06 nA L mg−1. pH electrodes showed a linear super-Nernstian response (74.2 ± 0.7 mV/pH unit) in a wide pH range (pH 4−9). The multi-analyte sensor array was validated in a flat plate bioreactor where simultaneous and instantaneous pH and DO profiles within a sulfide oxidizing biofilm were recorded. The electrodes spatial resolution, the monitoring sensitivity, and the minimally invasive features exhibited by the proposed microsensor improved biofilm monitoring performance, enabling the quantification of mass transfer resistances and the assessment of biological activity.
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22
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Wang X, Liu X, Lu S, Liu C, Gu Z, Zeng X, Ni Q. Culture of attached and suspended Rhodopseudomonas faecalis in the presence of decomposing fish feed. Microbiologyopen 2019; 8:e924. [PMID: 31482697 PMCID: PMC6925157 DOI: 10.1002/mbo3.924] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 07/25/2019] [Accepted: 07/26/2019] [Indexed: 11/26/2022] Open
Abstract
An approach to culturing attached and suspended forms of Rhodopseudomonas faecalis by using compound fish feed with tap water in transparent containers is reported in this study. The ratio of fish feed to tap water was 14.3–50.8 g/L, and no other inoculum or substances were added during the culture process. When the ratio of fish feed to tap water was 14.3 g/L, the highest total nitrogen, total phosphorus, and total dissolved carbon content recorded in the water in the containers were approximately 730 mg/L, 356 mg/L, and 1,620 mg/L, respectively, during the process of feed decay. Comamonas, Rhodopseudomonas, and Clostridium successively dominated during the culture process. Rhodopseudomonas was the most common dominant genus in both the attached and suspended forms when the water was dark red, and the relative operational taxonomic unit abundance reached 80‒89% and 24.8%, respectively. The dominant species was R. faecalis. The maximum thickness of attached bacteria and the biomass of attached Rhodopseudomonas reached up to 0.56 mm and 7.5 mg/cm2, respectively. This study provides a method for the mass culture of Rhodopseudomonas by using the fermentation of aquatic compound fish feed.
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Affiliation(s)
- Xiaodong Wang
- Fishery Machinery and Instrument Research Institute, Chinese Academy of Fisheries Sciences, Shanghai, China
| | - Xingguo Liu
- Fishery Machinery and Instrument Research Institute, Chinese Academy of Fisheries Sciences, Shanghai, China
| | - Shimin Lu
- Fishery Machinery and Instrument Research Institute, Chinese Academy of Fisheries Sciences, Shanghai, China
| | - Chong Liu
- Fishery Machinery and Instrument Research Institute, Chinese Academy of Fisheries Sciences, Shanghai, China
| | - Zhaojun Gu
- Fishery Machinery and Instrument Research Institute, Chinese Academy of Fisheries Sciences, Shanghai, China
| | - Xianlei Zeng
- Fishery Machinery and Instrument Research Institute, Chinese Academy of Fisheries Sciences, Shanghai, China
| | - Qi Ni
- Fishery Machinery and Instrument Research Institute, Chinese Academy of Fisheries Sciences, Shanghai, China
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Zhou JH, Yu HC, Ye KQ, Wang HY, Ruan YJ, Yu JM. Optimized aeration strategies for nitrogen removal efficiency: application of end gas recirculation aeration in the fixed bed biofilm reactor. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:28216-28227. [PMID: 31368074 DOI: 10.1007/s11356-019-06050-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 07/23/2019] [Indexed: 06/10/2023]
Abstract
Aeration strategy played an important role in reactor performance. In this study, when superficial upflow air velocity (SAV) decreased from 0.16 to 0.08 cm s-1, low dissolved oxygen concentration (DO) of 2.0 mg L-1 occurred in reactor. The required depth for anoxic microenvironment in biofilm decreased from 902.3 to 525.9 μm, which enhanced the growth of denitrifying bacteria and total nitrogen (TN) removal efficiency. However, decreasing aeration intensity resulted in insufficient hydraulic shear stress, which led to weak biofilm matrix structure. Mass biofilm detachment and reactor deterioration then occurred after 87 days of operation. An end gas recirculation aeration strategy was proposed to separately manipulate DO and aeration intensity. Low DO and high aeration intensity were simultaneously achieved, which enhanced the metabolism of denitrifying bacteria (such as Flavobacterium sp., Pseudorhodobacter sp., and Dok59 sp.) and EPS-producing bacteria (such as Zoogloea sp. and Rhodobacter sp.). Consequently, high TN removal performance (82.1 ± 2.7%) and stable biofilm structure were achieved.
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Affiliation(s)
- Jia Heng Zhou
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Hao Cheng Yu
- College of Environment, Zhejiang University of Technology, 310014, CNo. 18 Chaowang Road, Hangzhou, 310014, People's Republic of China
| | - Kai Qiang Ye
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Hong Yu Wang
- College of Environment, Zhejiang University of Technology, 310014, CNo. 18 Chaowang Road, Hangzhou, 310014, People's Republic of China
| | - Yun Jie Ruan
- College of Bio-systems Engineering and Food Science, Zhejiang University, |Hangzhou, 310058, China
| | - Jian Ming Yu
- College of Environment, Zhejiang University of Technology, 310014, CNo. 18 Chaowang Road, Hangzhou, 310014, People's Republic of China.
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Zhang L, Fu G, Zhang Z. Electricity generation and microbial community in long-running microbial fuel cell for high-salinity mustard tuber wastewater treatment. Bioelectrochemistry 2019; 126:20-28. [DOI: 10.1016/j.bioelechem.2018.11.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 11/05/2018] [Accepted: 11/05/2018] [Indexed: 12/19/2022]
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25
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Huang Y, Zheng Y, Li J, Liao Q, Fu Q, Xia A, Fu J, Sun Y. Enhancing microalgae biofilm formation and growth by fabricating microgrooves onto the substrate surface. BIORESOURCE TECHNOLOGY 2018; 261:36-43. [PMID: 29653332 DOI: 10.1016/j.biortech.2018.03.139] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 03/29/2018] [Accepted: 03/30/2018] [Indexed: 06/08/2023]
Abstract
Attachment of cells to substrate surface is the premise for biofilm formation. To shelter microalgae cells from fluid shear stress and offer larger areas for microalgae attachment, the inerratic microgrooves, which can act as anchor points that offer larger areas for microalgae attachment and induce vortex to protect cells from hydraulic shear stress, were designed and fabricated into substrate surface. The results indicated that the shear stress on the surface with V-grooves was weaker than that on the surface with U-grooves, and 45° V-grooves with the width of 200 μm were benefit for cells attachment. The initial attachment time was shortened to 50 min under the hydraulic shear stress of 0.02 Pa compared to that of 135 min on the surface without microgrooves. Subsequently, the biofilm biomass concentration on the surface with 45° V-grooves increased by 14.29% to 165.84 g m-2 compared with that on flat substrates.
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Affiliation(s)
- Yun Huang
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400044, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400044, China
| | - Yaping Zheng
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400044, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400044, China
| | - Jun Li
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400044, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400044, China
| | - Qiang Liao
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400044, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400044, China.
| | - Qian Fu
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400044, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400044, China
| | - Ao Xia
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400044, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400044, China
| | - Jingwei Fu
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400044, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400044, China
| | - Yahui Sun
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Chongqing University, Ministry of Education, Chongqing 400044, China; Institute of Engineering Thermophysics, Chongqing University, Chongqing 400044, China
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Li C, Brunner F, Wagner M, Lackner S, Horn H. Quantification of particulate matter attached to the bulk-biofilm interface and its influence on local mass transfer. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2017.12.044] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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28
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Skoneczny S, Cioch M. Modeling of continuous-flow bioreactors with a biofilm with the use of orthogonal collocation on finite elements. CHEM ENG COMMUN 2018. [DOI: 10.1080/00986445.2018.1423557] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Szymon Skoneczny
- Department of Chemical and Process Engineering, Cracow University of Technology, Cracow, Poland
| | - Monika Cioch
- Department of Fermentation Technology and Technical Microbiology, University of Agriculture in Krakow, Cracow, Poland
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30
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Pseudomonas sp. biofilm development on fresh-cut food equipment surfaces – a growth curve – fitting approach to building a comprehensive tool for studying surface contamination dynamics. FOOD AND BIOPRODUCTS PROCESSING 2018. [DOI: 10.1016/j.fbp.2017.11.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Luo X, Jedlicka SS, Jellison KL. Role of Wall Shear Stress in Cryptosporidium parvum Oocyst Attachment to Environmental Biofilms. Appl Environ Microbiol 2017; 83:e01533-17. [PMID: 29030438 PMCID: PMC5717202 DOI: 10.1128/aem.01533-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 10/02/2017] [Indexed: 11/20/2022] Open
Abstract
This study investigated Cryptosporidium parvum oocyst deposition onto biofilms as a function of shear stress under laminar or turbulent flow. Annular rotating bioreactors were used to grow stabilized stream biofilms at shear stresses ranging from 0.038 to 0.46 Pa. These steady-state biofilms were then used to assess the impact of hydrodynamic conditions on C. parvum oocyst attachment. C. parvum deposition onto biofilms followed a pseudo-second-order model under both laminar (after a lag phase) and turbulent flows. The total number of oocysts attached to the biofilm at steady state decreased as the hydrodynamic wall shear stress increased. The oocyst deposition rate constant increased with shear stress but decreased at high shear, suggesting that increasing wall shear stress results in faster attachment of Cryptosporidium due to higher mass transport until the shear forces exceed a critical limit that prevents oocyst attachment. These data show that oocyst attachment in the short and long term are impacted differently by shear: higher shear (to a certain limit) may be associated with faster initial oocyst attachment, but lower shear is associated with greater numbers of oocysts attached at equilibrium.IMPORTANCE This research provides experimental evidence to demonstrate that shear stress plays a critical role in protozoan-pathogen transport and deposition in environmental waters. The data presented in this work expand scientific understanding of Cryptosporidium attachment and fate, which will further influence the development of timely and accurate sampling strategies, as well as advanced water treatment technologies, to target protozoan pathogens in surface waters that serve as municipal drinking water sources.
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Affiliation(s)
- Xia Luo
- Department of Civil and Environmental Engineering, Lehigh University, Bethlehem, Pennsylvania, USA
| | - Sabrina S Jedlicka
- Department of Materials Science and Engineering, Lehigh University, Bethlehem, Pennsylvania, USA
| | - Kristen L Jellison
- Department of Civil and Environmental Engineering, Lehigh University, Bethlehem, Pennsylvania, USA
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Fernandez-Rojo L, Héry M, Le Pape P, Braungardt C, Desoeuvre A, Torres E, Tardy V, Resongles E, Laroche E, Delpoux S, Joulian C, Battaglia-Brunet F, Boisson J, Grapin G, Morin G, Casiot C. Biological attenuation of arsenic and iron in a continuous flow bioreactor treating acid mine drainage (AMD). WATER RESEARCH 2017; 123:594-606. [PMID: 28709104 DOI: 10.1016/j.watres.2017.06.059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 05/09/2017] [Accepted: 06/21/2017] [Indexed: 06/07/2023]
Abstract
Passive water treatments based on biological attenuation can be effective for arsenic-rich acid mine drainage (AMD). However, the key factors driving the biological processes involved in this attenuation are not well-known. Here, the efficiency of arsenic (As) removal was investigated in a bench-scale continuous flow channel bioreactor treating As-rich AMD (∼30-40 mg L-1). In this bioreactor, As removal proceeds via the formation of biogenic precipitates consisting of iron- and arsenic-rich mineral phases encrusting a microbial biofilm. Ferrous iron (Fe(II)) oxidation and iron (Fe) and arsenic removal rates were monitored at two different water heights (4 and 25 mm) and with/without forced aeration. A maximum of 80% As removal was achieved within 500 min at the lowest water height. This operating condition promoted intense Fe(II) microbial oxidation and subsequent precipitation of As-bearing schwertmannite and amorphous ferric arsenate. Higher water height slowed down Fe(II) oxidation, Fe precipitation and As removal, in relation with limited oxygen transfer through the water column. The lower oxygen transfer at higher water height could be partly counteracted by aeration. The presence of an iridescent floating film that developed at the water surface was found to limit oxygen transfer to the water column and delayed Fe(II) oxidation, but did not affect As removal. The bacterial community structure in the biogenic precipitates in the bottom of the bioreactor differed from that of the inlet water and was influenced to some extent by water height and aeration. Although potential for microbial mediated As oxidation was revealed by the detection of aioA genes, removal of Fe and As was mainly attributable to microbial Fe oxidation activity. Increasing the proportion of dissolved As(V) in the inlet water improved As removal and favoured the formation of amorphous ferric arsenate over As-sorbed schwertmannite. This study proved the ability of this bioreactor-system to treat extreme As concentrations and may serve in the design of future in-situ bioremediation system able to treat As-rich AMD.
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Affiliation(s)
- L Fernandez-Rojo
- Hydrosciences Montpellier, UMR 5569 CNRS-IRD-UM, CC57, 163 rue Auguste Broussonet, 34090, Montpellier, France
| | - M Héry
- Hydrosciences Montpellier, UMR 5569 CNRS-IRD-UM, CC57, 163 rue Auguste Broussonet, 34090, Montpellier, France
| | - P Le Pape
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), UMR 7590 CNRS-UPMC-IRD-MNHN, 4 place Jussieu, 75252, Paris cedex 05, France
| | - C Braungardt
- School of Geography, Earth and Environmental Sciences (Faculty of Science & Engineering), Plymouth University, United Kingdom; Hydrosciences Montpellier, UMR 5569 CNRS-IRD-UM, CC57, 163 rue Auguste Broussonet, 34090, Montpellier, France
| | - A Desoeuvre
- Hydrosciences Montpellier, UMR 5569 CNRS-IRD-UM, CC57, 163 rue Auguste Broussonet, 34090, Montpellier, France
| | - E Torres
- Hydrosciences Montpellier, UMR 5569 CNRS-IRD-UM, CC57, 163 rue Auguste Broussonet, 34090, Montpellier, France
| | - V Tardy
- Hydrosciences Montpellier, UMR 5569 CNRS-IRD-UM, CC57, 163 rue Auguste Broussonet, 34090, Montpellier, France
| | - E Resongles
- Hydrosciences Montpellier, UMR 5569 CNRS-IRD-UM, CC57, 163 rue Auguste Broussonet, 34090, Montpellier, France
| | - E Laroche
- Hydrosciences Montpellier, UMR 5569 CNRS-IRD-UM, CC57, 163 rue Auguste Broussonet, 34090, Montpellier, France
| | - S Delpoux
- Hydrosciences Montpellier, UMR 5569 CNRS-IRD-UM, CC57, 163 rue Auguste Broussonet, 34090, Montpellier, France
| | - C Joulian
- French Geological Survey (BRGM), 3 avenue Claude Guillemin, 45060, BP 36009, Orléans Cedex, France
| | - F Battaglia-Brunet
- French Geological Survey (BRGM), 3 avenue Claude Guillemin, 45060, BP 36009, Orléans Cedex, France
| | - J Boisson
- IRH Ingénieur Conseil, 197 avenue de Fronton, 31200, Toulouse, France
| | - G Grapin
- IRH Ingénieur Conseil, 427 rue Lavoisier - CS 50155, 54714, Ludres Cedex, France
| | - G Morin
- Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie (IMPMC), UMR 7590 CNRS-UPMC-IRD-MNHN, 4 place Jussieu, 75252, Paris cedex 05, France
| | - C Casiot
- Hydrosciences Montpellier, UMR 5569 CNRS-IRD-UM, CC57, 163 rue Auguste Broussonet, 34090, Montpellier, France.
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33
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Herrling MP, Weisbrodt J, Kirkland CM, Williamson NH, Lackner S, Codd SL, Seymour JD, Guthausen G, Horn H. NMR investigation of water diffusion in different biofilm structures. Biotechnol Bioeng 2017; 114:2857-2867. [PMID: 28755486 DOI: 10.1002/bit.26392] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 06/08/2017] [Accepted: 07/23/2017] [Indexed: 01/19/2023]
Abstract
Mass transfer in biofilms is determined by diffusion. Different mostly invasive approaches have been used to measure diffusion coefficients in biofilms, however, data on heterogeneous biomass under realistic conditions is still missing. To non-invasively elucidate fluid-structure interactions in complex multispecies biofilms pulsed field gradient-nuclear magnetic resonance (PFG-NMR) was applied to measure the water diffusion in five different types of biomass aggregates: one type of sludge flocs, two types of biofilm, and two types of granules. Data analysis is an important issue when measuring heterogeneous systems and is shown to significantly influence the interpretation and understanding of water diffusion. With respect to numerical reproducibility and physico-chemical interpretation, different data processing methods were explored: (bi)-exponential data analysis and the Γ distribution model. Furthermore, the diffusion coefficient distribution in relation to relaxation was studied by D-T2 maps obtained by 2D inverse Laplace transform (2D ILT). The results show that the effective diffusion coefficients for all biofilm samples ranged from 0.36 to 0.96 relative to that of water. NMR diffusion was linked to biofilm structure (e.g., biomass density, organic and inorganic matter) as observed by magnetic resonance imaging and to traditional biofilm parameters: diffusion was most restricted in granules with compact structures, and fast diffusion was found in heterotrophic biofilms with fluffy structures. The effective diffusion coefficients in the biomass were found to be broadly distributed because of internal biomass heterogeneities, such as gas bubbles, precipitates, and locally changing biofilm densities. Thus, estimations based on biofilm bulk properties in multispecies systems can be overestimated and mean diffusion coefficients might not be sufficiently informative to describe mass transport in biofilms and the near bulk.
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Affiliation(s)
- Maria P Herrling
- Department of Wastewater Engineering, Institute IWAR, Technische Universität Darmstadt, Darmstadt, Germany.,Department of Water Chemistry and Water Technology, Engler-Bunte-Institute, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Jessica Weisbrodt
- Department of Water Chemistry and Water Technology, Engler-Bunte-Institute, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Catherine M Kirkland
- Center of Biofilm Engineering, Montana State University, Bozeman, Montana.,Department of Mechanical and Industrial Engineering, Montana State University, Bozeman, Montana
| | - Nathan H Williamson
- Future Industries Institute, University of South Australia, Mawson Lakes Campus, Adelaide, Australia
| | - Susanne Lackner
- Department of Wastewater Engineering, Institute IWAR, Technische Universität Darmstadt, Darmstadt, Germany
| | - Sarah L Codd
- Center of Biofilm Engineering, Montana State University, Bozeman, Montana.,Department of Mechanical and Industrial Engineering, Montana State University, Bozeman, Montana
| | - Joseph D Seymour
- Center of Biofilm Engineering, Montana State University, Bozeman, Montana.,Department of Chemical and Biological Engineering, Montana State University, Bozeman, Montana
| | - Gisela Guthausen
- Department of Water Chemistry and Water Technology, Engler-Bunte-Institute, Karlsruhe Institute of Technology, Karlsruhe, Germany.,Institute of Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Harald Horn
- Department of Water Chemistry and Water Technology, Engler-Bunte-Institute, Karlsruhe Institute of Technology, Karlsruhe, Germany
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Mendoza-Lera C, Datry T. Relating hydraulic conductivity and hyporheic zone biogeochemical processing to conserve and restore river ecosystem services. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 579:1815-1821. [PMID: 27932213 DOI: 10.1016/j.scitotenv.2016.11.166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 11/23/2016] [Accepted: 11/23/2016] [Indexed: 06/06/2023]
Abstract
River management practices commonly attempt to improve habitat and ecological functioning (e.g. biogeochemical processing or retention of pollutants) by restoring hydrological exchange with the hyporheic zone (i.e. hyporheic flow) in an effort to increase mass transfer of solutes (nutrients, carbon and electron acceptors such as oxygen or nitrate). However, even when hyporheic flow is increased, often no significant changes in biogeochemical processing are detected. Some of these apparent paradox result from the simplistic assumption that there is a direct relationship between hyporheic flow and biogeochemical processing. We propose an alternative conceptual model that hyporheic flow is non-linearly related with biogeochemical processing. Based on the different solute mass transfer and area available for colonization among hydraulic conductivities, we hypothesize that biogeochemical processing in the hyporheic zone follows a Gaussian function depending on hyporheic hydraulic conductivity. After presenting the conceptual model and its domain of application, we discuss the potential implications, notably for river restoration and further hyporheic research.
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Affiliation(s)
- Clara Mendoza-Lera
- IRSTEA, UR MALY, Centre de Lyon, 5 rue de la Doua BP 32108, 69616 Villeurbanne Cedex, France.
| | - Thibault Datry
- IRSTEA, UR MALY, Centre de Lyon, 5 rue de la Doua BP 32108, 69616 Villeurbanne Cedex, France
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35
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Cao Y, Zhang C, Rong H, Zheng G, Zhao L. The effect of dissolved oxygen concentration (DO) on oxygen diffusion and bacterial community structure in moving bed sequencing batch reactor (MBSBR). WATER RESEARCH 2017; 108:86-94. [PMID: 27871745 DOI: 10.1016/j.watres.2016.10.063] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 10/20/2016] [Accepted: 10/23/2016] [Indexed: 05/13/2023]
Abstract
The effect of dissolved oxygen concentration (DO) on simultaneous nitrification and denitrification was studied in a moving bed sequencing batch reactor (MBSBR) by microelectrode measurements and by real-time PCR. In this system, the biofilm grew on polyurethane foam carriers used to treat municipal sewage at five DO concentrations (1.5, 2.5, 3.5, 4.5 and 5.5 mg/L). The results indicated that the MBSBR exhibited good removal of chemical oxygen demand (92.43%) and nitrogen (83.73%) when DO concentration was 2.5 mg/L. Increasing the oxygen concentration in the reactor was inhibitory to denitrification. Microelectrode measurements showed that the thickness of oxygen penetration increased from 1.2 to 2.6 mm when the DO concentration (from 1.5 mg/L to 5.5 mg/L) in the system increased. Oxygen diffusion was not significantly limited by the boundary layer surrounding the carrier and had the largest slope when DO concentration was 2.5 mg/L. The real-time PCR analysis indicated that the amount of the ammonia-oxidizing bacteria and nitrite-oxidizing bacteria increased slowly as DO concentration increased. The proportions of ammonia-oxidizing bacteria and nitrite-oxidizing bacteria, as a percentage of the total bacteria, were low with average values of 0.063% and 0.67%, respectively. When the DO concentration was 2.5 mg/L, oxygen diffusion was optimal and ensured the optimal bacterial community structure and activity; under these conditions, the MBSBR was efficient for total inorganic nitrogen removal. Changing the DO concentration could alter the aerobic zone and the bacterial community structure in the biofilm, directly influencing the simultaneous nitrification and denitrification activity in MBSBRs.
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Affiliation(s)
- Yongfeng Cao
- College of Civil Engineering, Guangzhou University, Guangzhou, 510006, China
| | - Chaosheng Zhang
- College of Civil Engineering, Guangzhou University, Guangzhou, 510006, China.
| | - Hongwei Rong
- College of Civil Engineering, Guangzhou University, Guangzhou, 510006, China
| | - Guilin Zheng
- College of Civil Engineering, Guangzhou University, Guangzhou, 510006, China
| | - Limin Zhao
- College of Civil Engineering, Guangzhou University, Guangzhou, 510006, China
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36
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Silva MCF, Araújo JDP, Campos JBLM. CFD studies coupling hydrodynamics and solid‐liquid mass transfer in slug flow for matter removal from tube walls. AIChE J 2016. [DOI: 10.1002/aic.15610] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Mónica C. F. Silva
- Centro de Estudos de Fenómenos de Transporte, Departamento de Engenharia QuímicaFaculdade de Engenharia da Universidade do PortoRua Dr. Roberto FriasPorto4200‐465 Portugal
| | - José D. P. Araújo
- Centro de Estudos de Fenómenos de Transporte, Departamento de Engenharia QuímicaFaculdade de Engenharia da Universidade do PortoRua Dr. Roberto FriasPorto4200‐465 Portugal
| | - João B. L. M. Campos
- Centro de Estudos de Fenómenos de Transporte, Departamento de Engenharia QuímicaFaculdade de Engenharia da Universidade do PortoRua Dr. Roberto FriasPorto4200‐465 Portugal
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37
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Spatial heterogeneity of biofouling under different cross-flow velocities in reverse osmosis membrane systems. J Memb Sci 2016. [DOI: 10.1016/j.memsci.2016.08.065] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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38
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Guimerà X, Dorado AD, Bonsfills A, Gabriel G, Gabriel D, Gamisans X. Dynamic characterization of external and internal mass transport in heterotrophic biofilms from microsensors measurements. WATER RESEARCH 2016; 102:551-560. [PMID: 27423049 DOI: 10.1016/j.watres.2016.07.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 07/05/2016] [Accepted: 07/06/2016] [Indexed: 06/06/2023]
Abstract
Knowledge of mass transport mechanisms in biofilm-based technologies such as biofilters is essential to improve bioreactors performance by preventing mass transport limitation. External and internal mass transport in biofilms was characterized in heterotrophic biofilms grown on a flat plate bioreactor. Mass transport resistance through the liquid-biofilm interphase and diffusion within biofilms were quantified by in situ measurements using microsensors with a high spatial resolution (<50 μm). Experimental conditions were selected using a mathematical procedure based on the Fisher Information Matrix to increase the reliability of experimental data and minimize confidence intervals of estimated mass transport coefficients. The sensitivity of external and internal mass transport resistances to flow conditions within the range of typical fluid velocities over biofilms (Reynolds numbers between 0.5 and 7) was assessed. Estimated external mass transfer coefficients at different liquid phase flow velocities showed discrepancies with studies considering laminar conditions in the diffusive boundary layer near the liquid-biofilm interphase. The correlation of effective diffusivity with flow velocities showed that the heterogeneous structure of biofilms defines the transport mechanisms inside biofilms. Internal mass transport was driven by diffusion through cell clusters and aggregates at Re below 2.8. Conversely, mass transport was driven by advection within pores, voids and water channels at Re above 5.6. Between both flow velocities, mass transport occurred by a combination of advection and diffusion. Effective diffusivities estimated at different biofilm densities showed a linear increase of mass transport resistance due to a porosity decrease up to biofilm densities of 50 g VSS·L(-1). Mass transport was strongly limited at higher biofilm densities. Internal mass transport results were used to propose an empirical correlation to assess the effective diffusivity within biofilms considering the influence of hydrodynamics and biofilm density.
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Affiliation(s)
- Xavier Guimerà
- Department of Mining Engineering and Natural Resources, Universitat Politècnica de Catalunya, Avinguda de les Bases de Manresa 61-73, 08240, Manresa, Spain.
| | - Antonio David Dorado
- Department of Mining Engineering and Natural Resources, Universitat Politècnica de Catalunya, Avinguda de les Bases de Manresa 61-73, 08240, Manresa, Spain.
| | - Anna Bonsfills
- Department of Mining Engineering and Natural Resources, Universitat Politècnica de Catalunya, Avinguda de les Bases de Manresa 61-73, 08240, Manresa, Spain.
| | - Gemma Gabriel
- Instituto de Microelectrónica de Barcelona, IMB-CNM (CSIC), Esfera UAB, Campus Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain; Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Zaragoza, Spain.
| | - David Gabriel
- Department of Chemical Engineering, Universitat Autònoma de Barcelona, Edifici Q, 08193, Bellaterra, Barcelona, Spain.
| | - Xavier Gamisans
- Department of Mining Engineering and Natural Resources, Universitat Politècnica de Catalunya, Avinguda de les Bases de Manresa 61-73, 08240, Manresa, Spain.
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Zhang Y, Pei G, Chen L, Zhang W. Metabolic dynamics of Desulfovibrio vulgaris biofilm grown on a steel surface. BIOFOULING 2016; 32:725-736. [PMID: 27299565 DOI: 10.1080/08927014.2016.1193166] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 05/18/2016] [Indexed: 06/06/2023]
Abstract
In this study, a comparative metabolomics approach combining gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) was applied first between planktonic cells and biofilms and then between pure cultures and biofilms of Desulfovibrio vulgaris. The results revealed that the overall metabolic level of the biofilm cells was down-regulated, especially for metabolites related to the central carbon metabolism, compared to the planktonic cells and the pure culture of D. vulgaris. In addition, pathway enrichment analysis of the 58 metabolites identified by GC-MS showed that fatty acid biosynthesis in the biofilm cells was up-regulated, suggesting that fatty acids may be important for the formation, maintenance and function of D. vulgaris biofilm. This study offers a valuable perspective on the metabolic dynamics of the D. vulgaris biofilm.
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Affiliation(s)
- Yang Zhang
- a Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology , Tianjin University , Tianjin , PR China
- b Key Laboratory of Systems Bioengineering (Ministry of Education) , Tianjin University , Tianjin , PR China
- c SynBio Research Platform , Collaborative Innovation Center of Chemical Science and Engineering , Tianjin , PR China
| | - Guangsheng Pei
- a Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology , Tianjin University , Tianjin , PR China
- b Key Laboratory of Systems Bioengineering (Ministry of Education) , Tianjin University , Tianjin , PR China
- c SynBio Research Platform , Collaborative Innovation Center of Chemical Science and Engineering , Tianjin , PR China
| | - Lei Chen
- a Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology , Tianjin University , Tianjin , PR China
- b Key Laboratory of Systems Bioengineering (Ministry of Education) , Tianjin University , Tianjin , PR China
- c SynBio Research Platform , Collaborative Innovation Center of Chemical Science and Engineering , Tianjin , PR China
| | - Weiwen Zhang
- a Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology , Tianjin University , Tianjin , PR China
- b Key Laboratory of Systems Bioengineering (Ministry of Education) , Tianjin University , Tianjin , PR China
- c SynBio Research Platform , Collaborative Innovation Center of Chemical Science and Engineering , Tianjin , PR China
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40
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Espinosa-Ortiz EJ, Pechaud Y, Lauchnor E, Rene ER, Gerlach R, Peyton BM, van Hullebusch ED, Lens PNL. Effect of selenite on the morphology and respiratory activity of Phanerochaete chrysosporium biofilms. BIORESOURCE TECHNOLOGY 2016; 210:138-145. [PMID: 26935326 DOI: 10.1016/j.biortech.2016.02.074] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 02/16/2016] [Accepted: 02/19/2016] [Indexed: 06/05/2023]
Abstract
The temporal and spatial effects of selenite (SeO3(2-)) on the physical properties and respiratory activity of Phanerochaete chrysosporium biofilms, grown in flow-cell reactors, were investigated using oxygen microsensors and confocal laser scanning microscopy (CLSM) imaging. Exposure of the biofilm to a SeO3(2-) load of 1.67mgSeL(-1)h(-1) (10mgSeL(-1) influent concentration), for 24h, resulted in a 20% reduction of the O2 flux, followed by a ∼10% decrease in the glucose consumption rate. Long-term exposure (4days) to SeO3(2-) influenced the architecture of the biofilm by creating a more compact and dense hyphal arrangement resulting in a decrease of biofilm thickness compared to fungal biofilms grown without SeO3(2-). To the best of our knowledge, this is the first time that the effect of SeO3(2-) on the aerobic respiratory activity on fungal biofilms is described.
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Affiliation(s)
| | - Yoan Pechaud
- Université Paris-Est, Laboratoire Géomatériaux et Environnement (EA 4508), UPEM, 77454 Marne-la-Vallée, France
| | - Ellen Lauchnor
- Center for Biofilm Engineering, Montana State University, 366 EPS, PO Box 173980, Bozeman, MT 59717, USA
| | - Eldon R Rene
- UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands
| | - Robin Gerlach
- Center for Biofilm Engineering, Montana State University, 366 EPS, PO Box 173980, Bozeman, MT 59717, USA
| | - Brent M Peyton
- Center for Biofilm Engineering, Montana State University, 366 EPS, PO Box 173980, Bozeman, MT 59717, USA
| | - Eric D van Hullebusch
- Université Paris-Est, Laboratoire Géomatériaux et Environnement (EA 4508), UPEM, 77454 Marne-la-Vallée, France
| | - Piet N L Lens
- UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands
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41
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Garrido-Baserba M, Asvapathanagul P, McCarthy GW, Gocke TE, Olson BH, Park HD, Al-Omari A, Murthy S, Bott CB, Wett B, Smeraldi JD, Shaw AR, Rosso D. Linking biofilm growth to fouling and aeration performance of fine-pore diffuser in activated sludge. WATER RESEARCH 2016; 90:317-328. [PMID: 26760484 DOI: 10.1016/j.watres.2015.12.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 11/18/2015] [Accepted: 12/09/2015] [Indexed: 06/05/2023]
Abstract
Aeration is commonly identified as the largest contributor to process energy needs in the treatment of wastewater and therefore garners significant focus in reducing energy use. Fine-pore diffusers are the most common aeration system in municipal wastewater treatment. These diffusers are subject to fouling and scaling, resulting in loss in transfer efficiency as biofilms form and change material properties producing larger bubbles, hindering mass transfer and contributing to increased plant energy costs. This research establishes a direct correlation and apparent mechanistic link between biofilm DNA concentration and reduced aeration efficiency caused by biofilm fouling. Although the connection between biofilm growth and fouling has been implicit in discussions of diffuser fouling for many years, this research provides measured quantitative connection between the extent of biofouling and reduced diffuser efficiency. This was clearly established by studying systematically the deterioration of aeration diffusers efficiency during a 1.5 year period, concurrently with the microbiological study of the biofilm fouling in order to understand the major factors contributing to diffuser fouling. The six different diffuser technologies analyzed in this paper included four different materials which were ethylene-propylene-diene monomer (EPDM), polyurethane, silicone and ceramic. While all diffusers foul eventually, some novel materials exhibited fouling resistance. The material type played a major role in determining the biofilm characteristics (i.e., growth rate, composition, and microbial density) which directly affected the rate and intensity at what the diffusers were fouled, whereas diffuser geometry exerted little influence. Overall, a high correlation between the increase in biofilm DNA and the decrease in αF was evident (CV < 14.0 ± 2.0%). By linking bacterial growth with aeration efficiency, the research was able to show quantitatively the causal connection between bacterial fouling and energy wastage during aeration.
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Affiliation(s)
- Manel Garrido-Baserba
- Department of Civil & Environmental Engineering, University of California, Irvine, CA 92697-2175, USA.
| | - Pitiporn Asvapathanagul
- Department of Civil & Environmental Engineering, University of California, Irvine, CA 92697-2175, USA; Department of Civil Engineering and Construction Engineering Management, California State University, Long Beach, CA 90840, USA
| | - Graham W McCarthy
- Department of Civil & Environmental Engineering, University of California, Irvine, CA 92697-2175, USA
| | - Thomas E Gocke
- Department of Civil & Environmental Engineering, University of California, Irvine, CA 92697-2175, USA
| | - Betty H Olson
- Department of Civil & Environmental Engineering, University of California, Irvine, CA 92697-2175, USA; Water-Energy Nexus Center, University of California, Irvine, CA 92697-2175, USA
| | - Hee-Deung Park
- School of Civil, Environmental and Architectural Engineering, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 136-713, South Korea
| | - Ahmed Al-Omari
- DC Water, 5000 Overlook Ave SW, Washington, DC 20032, USA
| | - Sudhir Murthy
- DC Water, 5000 Overlook Ave SW, Washington, DC 20032, USA
| | - Charles B Bott
- Hampton Roads Sanitation District, Virginia Beach, VA 23471-0911, USA
| | - Bernhard Wett
- ARAconsult, Unterbergerstraße 1, A-6020 Innsbruck, Austria
| | - Joshua D Smeraldi
- United States Environmental Protection Agency, 1200 Pennsylvania Ave NW, Washington, DC 20460, USA
| | - Andrew R Shaw
- Black & Veatch, 8400 Ward Pkwy, Kansas City, MO 64114, USA
| | - Diego Rosso
- Department of Civil & Environmental Engineering, University of California, Irvine, CA 92697-2175, USA; Water-Energy Nexus Center, University of California, Irvine, CA 92697-2175, USA.
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42
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Shen Y, Huang C, Monroy GL, Janjaroen D, Derlon N, Lin J, Espinosa-Marzal R, Morgenroth E, Boppart SA, Ashbolt NJ, Liu WT, Nguyen TH. Response of Simulated Drinking Water Biofilm Mechanical and Structural Properties to Long-Term Disinfectant Exposure. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:1779-87. [PMID: 26756120 PMCID: PMC5135099 DOI: 10.1021/acs.est.5b04653] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Mechanical and structural properties of biofilms influence the accumulation and release of pathogens in drinking water distribution systems (DWDS). Thus, understanding how long-term residual disinfectants exposure affects biofilm mechanical and structural properties is a necessary aspect for pathogen risk assessment and control. In this study, elastic modulus and structure of groundwater biofilms was monitored by atomic force microscopy (AFM) and optical coherence tomography (OCT) during three months of exposure to monochloramine or free chlorine. After the first month of disinfectant exposure, the mean stiffness of monochloramine- or free-chlorine-treated biofilms was 4 to 9 times higher than those before treatment. Meanwhile, the biofilm thickness decreased from 120 ± 8 μm to 93 ± 6-107 ± 11 μm. The increased surface stiffness and decreased biofilm thickness within the first month of disinfectant exposure was presumably due to the consumption of biomass. However, by the second to third month during disinfectant exposure, the biofilm mean stiffness showed a 2- to 4-fold decrease, and the biofilm thickness increased to 110 ± 7-129 ± 8 μm, suggesting that the biofilms adapted to disinfectant exposure. After three months of the disinfectant exposure process, the disinfected biofilms showed 2-5 times higher mean stiffness (as determined by AFM) and 6-13-fold higher ratios of protein over polysaccharide, as determined by differential staining and confocal laser scanning microscopy (CLSM), than the nondisinfected groundwater biofilms. However, the disinfected biofilms and nondisinfected biofilms showed statistically similar thicknesses (t test, p > 0.05), suggesting that long-term disinfection may not significantly remove net biomass. This study showed how biofilm mechanical and structural properties vary in response to a complex DWDS environment, which will contribute to further research on the risk assessment and control of biofilm-associated-pathogens in DWDS.
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Affiliation(s)
| | | | | | | | - Nicolas Derlon
- Eawag: Swiss Federal Institute of Aquatic Science and Technology , 8600 Dübendorf, Switzerland
| | | | | | - Eberhard Morgenroth
- Eawag: Swiss Federal Institute of Aquatic Science and Technology , 8600 Dübendorf, Switzerland
- Institute of Environmental Engineering, ETH Zürich , 8093 Zürich, Switzerland
| | | | - Nicholas J Ashbolt
- School of Public Health, University of Alberta , Edmonton, AB T6G 2G7 Canada
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Ranzinger F, Herrling MP, Lackner S, Grande VW, Baniodeh A, Powell AK, Horn H, Guthausen G. Direct surface visualization of biofilms with high spin coordination clusters using Magnetic Resonance Imaging. Acta Biomater 2016; 31:167-177. [PMID: 26675127 DOI: 10.1016/j.actbio.2015.12.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 12/01/2015] [Accepted: 12/03/2015] [Indexed: 01/02/2023]
Abstract
Magnetic Resonance Imaging is a powerful tool for the investigation of a biofilms' physical structure determining mass transport behavior which is of major importance in biofilm research. The entire biofilm is imaged in situ non-invasively and non-destructively on a meso-scale. In this study, different contrast agents were applied to study the biofilm's properties with the focus on mass transport, which is achieved by varying the contrast agents with respect to their NMR and interaction properties. The spatio-temporal tracking of these cluster, molecular and particulate contrast agents in biofilms was achieved by T1-, T2-weighted and proton density images during short (20h) and long (14 d) term exposures. The best biofilm surface visualization was observed when applying a new high spin coordination cluster (Fe10Gd10) showing a high affinity to the biofilm's surface and a fast immobilization within minutes. Contrarily, the small molecular contrast agents show no immobilization and fully penetrated into the biofilm. A concentration equilibrium was observed which was confirmed in back diffusion experiments. Interactions between larger nanoparticulate contrast agents and the biofilm required hours to achieve immobilization. Thus, the penetration depth into the biofilm is predominantly size-dependent. Here, it is shown that biofilm surface interactions can be observed in situ and spatio-temporarily resolved. The reported methodology demonstrates a new means to explore mass transfer of various substances in biofilms. STATEMENT OF SIGNIFICANCE In biofilm research, the investigation of the biofilms' physical structure is of high relevance for the understanding of mass transport processes. However, commonly used imaging techniques for biofilm imaging such as CLSM or electron microscopy rarely visualize the real biofilm due to their invasiveness and destructiveness. Magnetic Resonance Imaging (MRI) represents the ideal tool to image the biofilm in situ, non-invasively and non-destructively with a spatial resolution of several 10μm. To gain specific structural and functional information, a variety of MRI contrast agents (molecular and particulate) was applied with different properties for the first time. Results elucidate the interactions between the biofilms' surface and the contrast agents and open a new field for biotechnological applications by functional contrast enhancement.
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44
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Li C, Wagner M, Lackner S, Horn H. Assessing the influence of biofilm surface roughness on mass transfer by combining optical coherence tomography and two-dimensional modeling. Biotechnol Bioeng 2015; 113:989-1000. [PMID: 26498328 DOI: 10.1002/bit.25868] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 10/13/2015] [Accepted: 10/19/2015] [Indexed: 11/09/2022]
Abstract
Imaging and modeling are two major approaches in biofilm research to understand the physical and biochemical processes involved in biofilm development. However, they are often used separately. In this study we combined these two approaches to investigate substrate mass transfer and mass flux. Cross-sectional biofilm images were acquired by means of optical coherence tomography (OCT) for biofilms grown on carriers. A 2D biofilm model was developed incorporating OCT images as well as a simplified biofilm geometry serving as structural templates. The model incorporated fluid flow, substrate transfer and biochemical conversion of substrates and simulated the hydrodynamics surrounding the biofilm structure as well as the substrate distribution. The method allowed detailed analysis of the hydrodynamics and mass transfer characteristics at the micro-scale. Biofilm activity with respect to substrate fluxes was compared among different combinations of flow, substrate availability and biomass density. The combined approach revealed that higher substrate fluxes at heterogeneous biofilm surface under two conditions: pure diffusion and when high flow velocity along the biofilms surface renders the whole liquid-biofilm interface to be highly active. In-between the two conditions the substrate fluxes across the surface of smooth biofilm geometry were higher than that of the heterogeneous biofilms.
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Affiliation(s)
- Chunyan Li
- Chair of Water Chemistry, Water Technology, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9, Karlsruhe, 76131, Germany
| | - Michael Wagner
- Chair of Water Chemistry, Water Technology, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9, Karlsruhe, 76131, Germany.,Institute of Functional Interfaces, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
| | - Susanne Lackner
- Chair of Water Chemistry, Water Technology, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9, Karlsruhe, 76131, Germany.,Urban Bioengineering for Resource Recovery, Bauhaus-Institute for Infrastructure Solutions, Bauhaus-Universityät Weimar, Weimar, Germany
| | - Harald Horn
- Chair of Water Chemistry, Water Technology, Karlsruhe Institute of Technology, Engler-Bunte-Ring 9, Karlsruhe, 76131, Germany.
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45
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Nogueira BL, Pérez J, van Loosdrecht MCM, Secchi AR, Dezotti M, Biscaia EC. Determination of the external mass transfer coefficient and influence of mixing intensity in moving bed biofilm reactors for wastewater treatment. WATER RESEARCH 2015; 80:90-98. [PMID: 25996756 DOI: 10.1016/j.watres.2015.05.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 04/25/2015] [Accepted: 05/05/2015] [Indexed: 06/04/2023]
Abstract
In moving bed biofilm reactors (MBBR), the removal of pollutants from wastewater is due to the substrate consumption by bacteria attached on suspended carriers. As a biofilm process, the substrates are transported from the bulk phase to the biofilm passing through a mass transfer resistance layer. This study proposes a methodology to determine the external mass transfer coefficient and identify the influence of the mixing intensity on the conversion process in-situ in MBBR systems. The method allows the determination of the external mass transfer coefficient in the reactor, which is a major advantage when compared to the previous methods that require mimicking hydrodynamics of the reactor in a flow chamber or in a separate vessel. The proposed methodology was evaluated in an aerobic lab-scale system operating with COD removal and nitrification. The impact of the mixing intensity on the conversion rates for ammonium and COD was tested individually. When comparing the effect of mixing intensity on the removal rates of COD and ammonium, a higher apparent external mass transfer resistance was found for ammonium. For the used aeration intensities, the external mass transfer coefficient for ammonium oxidation was ranging from 0.68 to 13.50 m d(-1) and for COD removal 2.9 to 22.4 m d(-1). The lower coefficient range for ammonium oxidation is likely related to the location of nitrifiers deeper in the biofilm. The measurement of external mass transfer rates in MBBR will help in better design and evaluation of MBBR system-based technologies.
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Affiliation(s)
- Bruno L Nogueira
- Programa de Engenharia Química, COPPE - Universidade Federal do Rio de Janeiro - Centro de Tecnologia, Bl. G-115, Ilha do Fundão, CEP: 21941-972 Rio de Janeiro, RJ, Brazil; Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - Julio Pérez
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - Argimiro R Secchi
- Programa de Engenharia Química, COPPE - Universidade Federal do Rio de Janeiro - Centro de Tecnologia, Bl. G-115, Ilha do Fundão, CEP: 21941-972 Rio de Janeiro, RJ, Brazil.
| | - Márcia Dezotti
- Programa de Engenharia Química, COPPE - Universidade Federal do Rio de Janeiro - Centro de Tecnologia, Bl. G-115, Ilha do Fundão, CEP: 21941-972 Rio de Janeiro, RJ, Brazil
| | - Evaristo C Biscaia
- Programa de Engenharia Química, COPPE - Universidade Federal do Rio de Janeiro - Centro de Tecnologia, Bl. G-115, Ilha do Fundão, CEP: 21941-972 Rio de Janeiro, RJ, Brazil
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46
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Shi Y, Wu G, Wei N, Hu H. Denitrification and biofilm growth in a pilot-scale biofilter packed with suspended carriers for biological nitrogen removal from secondary effluent. J Environ Sci (China) 2015; 32:35-41. [PMID: 26040729 DOI: 10.1016/j.jes.2014.12.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Revised: 12/10/2014] [Accepted: 12/16/2014] [Indexed: 06/04/2023]
Abstract
Tertiary denitrification is an effective method for nitrogen removal from wastewater. A pilot-scale biofilter packed with suspended carriers was operated for tertiary denitrification with ethanol as the organic carbon source. Long-term performance, biokinetics of denitrification and biofilm growth were evaluated under filtration velocities of 6, 10 and 14 m/hr. The pilot-scale biofilter removed nitrate from the secondary effluent effectively, and the nitrate nitrogen (NO3-N) removal percentage was 82%, 78% and 55% at the filtration velocities of 6, 10 and 14 m/hr, respectively. At the filtration velocities of 6 and 10 m/hr, the nitrate removal loading rate increased with increasing influent nitrate loading rates, while at the filtration velocity of 14 m/hr, the removal loading rate and the influent loading rate were uncorrelated. During denitrification, the ratio of consumed chemical oxygen demand to removed NO3-N was 3.99-4.52 mg/mg. Under the filtration velocities of 6, 10 and 14 m/hr, the maximum denitrification rate was 3.12, 4.86 and 4.42 g N/(m2·day), the half-saturation constant was 2.61, 1.05 and 1.17 mg/L, and the half-order coefficient was 0.22, 0.32 and 0.24(mg/L)1/2/min, respectively. The biofilm biomass increased with increasing filtration velocity and was 2845, 5124 and 7324 mg VSS/m2 at filtration velocities of 6, 10 and 14 m/hr, respectively. The highest biofilm density was 44 mg/cm3 at the filtration velocity of 14 m/hr. Due to the low influent loading rate, biofilm biomass and thickness were lowest at the filtration velocity of 6m/hr.
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Affiliation(s)
- Yunhong Shi
- Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China.
| | - Guangxue Wu
- Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China.
| | - Nan Wei
- Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
| | - Hongying Hu
- Key Laboratory of Microorganism Application and Risk Control (MARC) of Shenzhen, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
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Li X, Song JL, Culotti A, Zhang W, Chopp DL, Lu N, Packman AI. Methods for characterizing the co-development of biofilm and habitat heterogeneity. J Vis Exp 2015. [PMID: 25866914 DOI: 10.3791/52602] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Biofilms are surface-attached microbial communities that have complex structures and produce significant spatial heterogeneities. Biofilm development is strongly regulated by the surrounding flow and nutritional environment. Biofilm growth also increases the heterogeneity of the local microenvironment by generating complex flow fields and solute transport patterns. To investigate the development of heterogeneity in biofilms and interactions between biofilms and their local micro-habitat, we grew mono-species biofilms of Pseudomonas aeruginosa and dual-species biofilms of P. aeruginosa and Escherichia coli under nutritional gradients in a microfluidic flow cell. We provide detailed protocols for creating nutrient gradients within the flow cell and for growing and visualizing biofilm development under these conditions. We also present protocols for a series of optical methods to quantify spatial patterns in biofilm structure, flow distributions over biofilms, and mass transport around and within biofilm colonies. These methods support comprehensive investigations of the co-development of biofilm and habitat heterogeneity.
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Affiliation(s)
- Xiaobao Li
- Department of Civil and Environmental Engineering, Northwestern University;
| | - Jisun L Song
- Department of Chemical and Biological Engineeering, Northwestern University
| | - Alessandro Culotti
- Department of Civil and Environmental Engineering, Northwestern University
| | - Wei Zhang
- Department of Civil and Environmental Engineering, Northwestern University
| | - David L Chopp
- Department of Applied Mathematics and Engineering Sciences, Northwestern University
| | - Nanxi Lu
- Department of Civil and Environmental Engineering, Northwestern University
| | - Aaron I Packman
- Department of Civil and Environmental Engineering, Northwestern University
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48
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Herrling MP, Guthausen G, Wagner M, Lackner S, Horn H. Determining the flow regime in a biofilm carrier by means of magnetic resonance imaging. Biotechnol Bioeng 2015; 112:1023-32. [DOI: 10.1002/bit.25510] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 11/19/2014] [Indexed: 11/08/2022]
Affiliation(s)
- Maria P. Herrling
- Chair of Water Chemistry Water Technology; Karlsruhe Institute of Technology; Engler-Bunte-Ring 1 Karlsruhe 76131 Germany
| | - Gisela Guthausen
- Pro2NMR; Institute for Biological Interfaces and Institute for Mechanical Process Engineering and Mechanics; Karlsruhe Institute of Technology; Karlsruhe Germany
| | - Michael Wagner
- Chair of Water Chemistry Water Technology; Karlsruhe Institute of Technology; Engler-Bunte-Ring 1 Karlsruhe 76131 Germany
- Institute of Functional Interfaces; Karlsruhe Institute of Technology; Eggenstein-Leopoldshafen Germany
| | - Susanne Lackner
- Chair of Water Chemistry Water Technology; Karlsruhe Institute of Technology; Engler-Bunte-Ring 1 Karlsruhe 76131 Germany
| | - Harald Horn
- Chair of Water Chemistry Water Technology; Karlsruhe Institute of Technology; Engler-Bunte-Ring 1 Karlsruhe 76131 Germany
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49
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Bucs SS, Valladares Linares R, van Loosdrecht MCM, Kruithof JC, Vrouwenvelder JS. Impact of organic nutrient load on biomass accumulation, feed channel pressure drop increase and permeate flux decline in membrane systems. WATER RESEARCH 2014; 67:227-242. [PMID: 25282091 DOI: 10.1016/j.watres.2014.09.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 07/18/2014] [Accepted: 09/04/2014] [Indexed: 06/03/2023]
Abstract
The influence of organic nutrient load on biomass accumulation (biofouling) and pressure drop development in membrane filtration systems was investigated. Nutrient load is the product of nutrient concentration and linear flow velocity. Biofouling - excessive growth of microbial biomass in membrane systems - hampers membrane performance. The influence of biodegradable organic nutrient load on biofouling was investigated at varying (i) crossflow velocity, (ii) nutrient concentration, (iii) shear, and (iv) feed spacer thickness. Experimental studies were performed with membrane fouling simulators (MFSs) containing a reverse osmosis (RO) membrane and a 31 mil thick feed spacer, commonly applied in practice in RO and nanofiltration (NF) spiral-wound membrane modules. Numerical modeling studies were done with identical feed spacer geometry differing in thickness (28, 31 and 34 mil). Additionally, experiments were done applying a forward osmosis (FO) membrane with varying spacer thickness (28, 31 and 34 mil), addressing the permeate flux decline and biofilm development. Assessed were the development of feed channel pressure drop (MFS studies), permeate flux (FO studies) and accumulated biomass amount measured by adenosine triphosphate (ATP) and total organic carbon (TOC). Our studies showed that the organic nutrient load determined the accumulated amount of biomass. The same amount of accumulated biomass was found at constant nutrient load irrespective of linear flow velocity, shear, and/or feed spacer thickness. The impact of the same amount of accumulated biomass on feed channel pressure drop and permeate flux was influenced by membrane process design and operational conditions. Reducing the nutrient load by pretreatment slowed-down the biofilm formation. The impact of accumulated biomass on membrane performance was reduced by applying a lower crossflow velocity and/or a thicker and/or a modified geometry feed spacer. The results indicate that cleanings can be delayed but are unavoidable.
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Affiliation(s)
- Sz S Bucs
- King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Thuwal, Saudi Arabia; Department of Biotechnology, Faculty of Applied Sciences, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - R Valladares Linares
- King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Thuwal, Saudi Arabia; Department of Biotechnology, Faculty of Applied Sciences, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - M C M van Loosdrecht
- Department of Biotechnology, Faculty of Applied Sciences, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands
| | - J C Kruithof
- Wetsus, Centre of Excellence for Sustainable Water Technology, Agora 1, P.O. Box 1113, 8900 CC Leeuwarden, The Netherlands
| | - J S Vrouwenvelder
- King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Thuwal, Saudi Arabia; Department of Biotechnology, Faculty of Applied Sciences, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands; Wetsus, Centre of Excellence for Sustainable Water Technology, Agora 1, P.O. Box 1113, 8900 CC Leeuwarden, The Netherlands.
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D'Acunto B, Frunzo L, Klapper I, Mattei MR. Modeling multispecies biofilms including new bacterial species invasion. Math Biosci 2014; 259:20-6. [PMID: 25447810 DOI: 10.1016/j.mbs.2014.10.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 10/19/2014] [Accepted: 10/21/2014] [Indexed: 10/24/2022]
Abstract
A mathematical model for multispecies biofilm evolution based on continuum approach and mass conservation principles is presented. The model can describe biofilm growth dynamics including spatial distribution of microbial species, substrate concentrations, attachment, and detachment, and, in particular, is able to predict the biological process of colonization of new species and transport from bulk liquid to biofilm (or vice-versa). From a mathematical point of view, a significant feature is the boundary condition related to biofilm species concentrations on the biofilm free boundary. These data, either for new or for already existing species, are not required by this model, but rather can be predicted as results. Numerical solutions for representative examples are obtained by the method of characteristics. Results indicate that colonizing bacteria diffuse into biofilm and grow only where favorable environmental conditions exist for their development.
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Affiliation(s)
- B D'Acunto
- University of Naples "Federico II", Department of Mathematics and Applications, via Claudio 21, 80125 Naples, Italy.
| | - L Frunzo
- University of Naples "Federico II", Department of Mathematics and Applications, via Claudio 21, 80125 Naples, Italy.
| | - I Klapper
- Temple University, Department of Mathematics, 1805 N. Broad St., Philadelphia, 19122 PA, USA.
| | - M R Mattei
- University of Cassino and Southern Lazio, Department of Civil and Mechanical Engineering, via Di Biasio 43, 03043 Cassino, Italy.
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