Modeling and analysis of layered stationary anaerobic granular biofilms

Tartakovsky, B.; Guiot, Serge R.

doi:10.1002/(sici)1097-0290(19970420)54:2<122::aid-bit4>3.0.co;2-n

Cited by 23 publications

(9 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, a layered biofilm may be formed, where exoelectrogens are located at the biofilm core and acidogenic microorganisms proliferate at the biofilm surface. Biofilm stratification is often observed in reactors where anaerobic biofilms exist and is beneficial for the biodegradation of complex organic molecules [16].…”

Section: Discussionmentioning

confidence: 99%

Biocatalyzed hydrogen production in a continuous flow microbial fuel cell with a gas phase cathode

Tartakovsky

Manuel

Neburchilov

et al. 2008

Journal of Power Sources

Self Cite

116

View full text Add to dashboard Cite

Biocatalyzed hydrogen production in a continuous flow microbial fuel cell with a gas phase cathode Tartakovsky, B.; Manuel, M.-F.; Neburchilov, V.; Wang, H.; Guiot, S. R.Contact us / Contactez nous: nparc.cisti@nrc-cnrc.gc.ca. abstractA single liquid chamber microbial fuel cell (MFC) with a gas-collection compartment was continuously operated under electrically assisted conditions for hydrogen production. Graphite felt was used for anode construction, while the cathode was made of Pd/Pt coated Toray carbon fiber paper with a catalyst loading of 0.5 mg cm −2 . To achieve hydrogen production, the MFC was connected to a power supply and operated at voltages in a range of 0.5-1.3 V. Either acetate or glucose was used as a source of carbon. At an acetate load of1.67g(L A d) −1 , the volumetric rate of hydrogen production reached 0.98 L STP (L A d) −1 when a voltage of 1.16 V was applied. This corresponded to a hydrogen yield of 2 mol (mol-acetate) −1 with a 50% conversion efficiency. Throughout the experiment, MFC efficiency was adversely affected by the metabolic activity of methanogenic microorganisms, which competed with exoelectrogenic microorganisms for the carbon source and consumed part of the hydrogen produced at the cathode.Crown

show abstract

Section: Discussionmentioning

confidence: 99%

Biocatalyzed hydrogen production in a continuous flow microbial fuel cell with a gas phase cathode

Tartakovsky

Manuel

Neburchilov

et al. 2008

Journal of Power Sources

Self Cite

116

View full text Add to dashboard Cite

show abstract

“…For the sake of simplicity, intermediates of the anaerobic degradation of sucrose such as pyruvate, volatile fatty acids (VFAs), and acetate were grouped as a single entity, denoted as s 3 . Other simplifying assumptions used in the model are common in modeling of biofilms and can be found elsewhere (29,31).…”

Section: Methodsmentioning

confidence: 99%

Microstructure of Anaerobic Granules Bioaugmented with Desulfitobacterium frappieri PCP-1

Lanthier¹,

Tartakovsky

Villemur³

et al. 2002

Appl Environ Microbiol

Self Cite

View full text Add to dashboard Cite

Oligonucleotide probes were used to study the structure of anaerobic granular biofilm originating from a pentachlorophenol-fed upflow anaerobic sludge bed reactor augmented with Desulfitobacterium frappieri PCP-1. Fluorescence in situ hybridization demonstrated successful colonization of anaerobic granules by strain PCP-1. Scattered microcolonies of strain PCP-1 were detected on the biofilm surface after 3 weeks of reactor operation, and a dense outer layer of strain PCP-1 was observed after 9 weeks. Hybridization with probes specific for Eubacteria and Archaea probes showed that Eubacteria predominantly colonized the outer layer, while Archaea were observed in the granule interior. Mathematical simulations showed a distribution similar to that observed experimentally when using a specific growth rate of 2.2 day ؊1 and a low bacterial diffusion of 10 ؊7 dm 2 day ؊1 . Also, the simulations showed that strain PCP-1 proliferation in the outer biofilm layer provided excellent protection of the biofilm from pentachlorophenol toxicity.Bioaugmentation of a natural bacterial community is a potentially efficient approach for maximizing the degradation performance of a biological system. However, the fate of a newly introduced strain strongly depends on its interactions with the members of the indigenous bacterial consortium. As a result, the disappearance of introduced strains was observed as often as their retention (4, 5, 7). Bioaugmentation attempts are most successful when a newly introduced strain establishes commensal or mutualistic relationships within a natural consortium, e.g., by degrading substances otherwise toxic to the consortium.The anaerobic degradation of chlorinated compounds by indigenous microorganisms often results in incomplete dechlorination and thus can benefit from bioaugmentation. In particular, bioaugmentation of an upflow anaerobic sludge bed (UASB) reactor with Dehalospirillum multivorans led to a transformation of perchloroethylene (PCE) to dichloroethylene, an improvement compared to a noninoculated control, which only transformed PCE to trichloroethene (17). Ahring et al.(1) introduced a 3-chlorobenzoate dechlorination activity in a UASB reactor by bioaugmentation with Desulfomonile tiedjei. Also, Christiansen and Ahring (7) demonstrated inoculation of a UASB reactor containing sterilized anaerobic granules with a pentachlorophenol (PCP)-degrading strain of Desulfitobacterium hafniense.In our previous work, a UASB reactor degrading PCP was successfully inoculated with the PCP-degrading strain Desulfitobacterium frappieri PCP-1 (28). This strain is the only isolated anaerobic microorganism capable of PCP dehalogenation to 3-chlorophenol (3). Proliferation of strain PCP-1 allowed a substantial increase of the volumetric PCP load from 5 to 80 mg/liter of reaction volume/day with a PCP removal efficiency of 99% and a dechlorination efficiency of not less than 91%. Following inoculation, the density of strain PCP-1 was found to increase from 10 6 to 10 10 cells/g of volatile suspended solids (V...

show abstract

“…There are already some granulation models available in the literature, but they do not describe a process of de novo granulation and only describe the kinetics of anaerobic digestion with an already mature granular consortia. For example, one of the earliest models [13] assumes a layered granule structure with a homogeneous distribution of microbial groups from the very beginning of the simulation. Authors describe the kinetics of substrate transformation in a mature granule that reached a steady state.…”

Section: Introductionmentioning

confidence: 99%

Modeling de novo granulation of anaerobic sludge

et al. 2017

View full text Add to dashboard Cite

BackgroundA unique combination of mechanical, physiochemical and biological forces influences granulation during processes of anaerobic digestion. Understanding this process requires a systems biology approach due to the need to consider not just single-cell metabolic processes, but also the multicellular organization and development of the granule.ResultsIn this computational experiment, we address the role that physiochemical and biological processes play in granulation and provide a literature-validated working model of anaerobic granule de novo formation. The agent-based model developed in a cDynoMiCs simulation environment successfully demonstrated a de novo granulation in a glucose fed system, with the average specific methanogenic activity of 1.11 ml C H 4/g biomass and formation of a 0.5 mm mature granule in 33 days. The simulated granules exhibit experimental observations of radial stratification: a central dead core surrounded by methanogens then encased in acidogens. Practical application of the granulation model was assessed on the anaerobic digestion of low-strength wastewater by measuring the changes in methane yield as experimental configuration parameters were systematically searched.ConclusionsIn the model, the emergence of multicellular organization of anaerobic granules from randomly mixed population of methanogens and acidogens was observed and validated. The model of anaerobic de novo granulation can be used to predict the morphology of the anaerobic granules in a alternative substrates of interest and to estimate methane potential of the resulting microbial consortia. The study demonstrates a successful integration of a systems biology approach to model multicellular systems with the engineering of an efficient anaerobic digestion system.

show abstract

Modeling and analysis of layered stationary anaerobic granular biofilms

Cited by 23 publications

References 21 publications

Biocatalyzed hydrogen production in a continuous flow microbial fuel cell with a gas phase cathode

Biocatalyzed hydrogen production in a continuous flow microbial fuel cell with a gas phase cathode

Microstructure of Anaerobic Granules Bioaugmented with Desulfitobacterium frappieri PCP-1

Modeling de novo granulation of anaerobic sludge

Contact Info

Product

Resources

About