Hierarchical simulator of biofilm growth and dynamics in granular porous materials

Kapellos, George E.; Alexiou, Terpsichori S.; Payatakes, A. C.

doi:10.1016/j.advwatres.2006.05.030

Cited by 99 publications

(86 citation statements)

References 71 publications

(87 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Soil is a major habitat for bacteria, including P. aeruginosa (16,41). Clogging of soil-like porous materials is a primary concern in waste-water treatment reactors (6) and has been studied extensively (26,27,31,32,(42)(43)(44)(45)(46). Direct observations of biofilm dynamics inside soil have not been possible because these environments are generally opaque beyond the first layer of granules.…”

Section: Resultsmentioning

confidence: 99%

Biofilm streamers cause catastrophic disruption of flow with consequences for environmental and medical systems

Drescher

Shen

Bassler

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

305

396

View full text Add to dashboard Cite

Biofilms are antibiotic-resistant, sessile bacterial communities that occupy most moist surfaces on Earth and cause chronic and medical device-associated infections. Despite their importance, basic information about biofilm dynamics in common ecological environments is lacking. Here, we demonstrate that flow through soil-like porous materials, industrial filters, and medical stents dramatically modifies the morphology of Pseudomonas aeruginosa biofilms to form 3D streamers, which, over time, bridge the spaces between obstacles and corners in nonuniform environments. We discovered that accumulation of surface-attached biofilm has little effect on flow through such environments, whereas biofilm streamers cause sudden and rapid clogging. We demonstrate that flow-induced shedding of extracellular matrix from surface-attached biofilms generates a sievelike network that captures cells and other biomass, which add to the existing network, causing exponentially fast clogging independent of growth. These results suggest that biofilm streamers are ubiquitous in nature and strongly affect flow through porous materials in environmental, industrial, and medical systems.bioclogging | biofouling | porous media I n the laboratory, bacteria are usually grown as planktonic cells in shaken suspensions, which differs dramatically from the natural environments of most microbes. In their natural habitats, bacteria often live in biofilms (1-3), which are tightly packed, surface-associated assemblies of bacteria that are bound together by extracellular polymeric substances (4, 5). Although biofilms are desirable in waste-water treatment (6), biofilms primarily cause undesirable effects such as chronic infections or clogging of industrial flow systems (1-3). Cells in biofilms display many behavioral differences from planktonic cells, such as a 1,000-fold increase in tolerance to antibiotics (7,8), an altered transcriptome (9-11), and spatially heterogeneous metabolic activity (12, 13). Some of these physiological peculiarities of biofilm-dwelling cells may be due to strong gradients of nutrients and metabolites, which also affect biofilm morphology and composition (14, 15). However, little is known about how physical aspects of the environment affect biofilm dynamics.The opportunistic pathogen Pseudomonas aeruginosa has become a model organism for biofilm studies largely because it forms biofilms in diverse habitats, including soil, rivers, sewage, and medical devices in humans (1, 2, 16). Two features are common to all of these environments: First, the presence of rough surfaces, which at the microscopic level reduce to surfaces with many corners, and second, a pressure-driven flow. The standard assay for growing biofilms in the laboratory abstracts from these realistic environments by typically using a smooth surface as a substrate, and either no flow or a pump to force nutritious medium across the biofilm at a constant flow rate (17-19). These standard assays have enabled the identification of several genes involved in biofilm develo...

show abstract

Section: Resultsmentioning

confidence: 99%

Biofilm streamers cause catastrophic disruption of flow with consequences for environmental and medical systems

Drescher

Shen

Bassler

et al. 2013

Proc. Natl. Acad. Sci. U.S.A.

305

396

View full text Add to dashboard Cite

show abstract

“…Such effects could include 105 long-range interactions for example caused by the presence of neighboring fibers in a hollow-fiber membrane module. Although biofilm models have been developed to consider these types of processes, (4,16), the assumption seems justifiable since full scale MABR design are insufficiently developed at present.…”

Section: Model Assumptionsmentioning

confidence: 99%

Studies on the effect of concentration of a self-inhibitory substrate on biofilm reaction rate under co-diffusion and counter-diffusion configurations

Syron

Kelly

Casey

2009

Journal of Membrane Science

View full text Add to dashboard Cite

A simple mathematical model was developed to investigate the utilzation rate of a selfinhibitory substrate in idealised biofilm reactors operating with either counter-diffusion or co-diffusion of oxygen and phenol. This study has implications for the development of membrane-supported biofilm technologies, such as the membrane-aerated biofilm reactor. 5An unsteady-state formulation of the model was used to investigate the effect of shock loads of phenol on biofilm performance. It was found that the counter-diffusion configuration may be advantageous under high phenol concentrations provided the biofilm thickness is above a critical value. The performance advantage of the counter-diffusion configuration is gained by the presence of an oxygen depleted layer, adjacent to the liquid-10 biofilm interface which acts as a diffusive barrier to phenol transport to the region of respiratory activity.

show abstract

“…Much effort has been invested into understanding biodegradation and bioclogging in porous media (Baveye and Valocchi 1989;Dillon and Fauci 2000;Kapellos et al 2007;Rittmann 1993;Rosenzweig et al 2009;Van Noorden et al 2010). To describe these processes at the REV scale, macroscale models were formulated by the volumeaveraging technique Vandevivere et al 1995).…”

Section: Introductionmentioning

confidence: 99%

Pore-Network Modeling of Solute Transport and Biofilm Growth in Porous Media

Qin

Hassanizadeh

2015

Transp Porous Med

View full text Add to dashboard Cite

In this work, a pore-network (PN) model for solute transport and biofilm growth in porous media was developed. Compared to previous studies of biofilm growth, it has two new features. First, the constructed pore network gives a better representation of a porous medium. Second, instead of using a constant mass exchange coefficient for solute transport between water phase and biofilm, a variable coefficient as a function of biofilm volume fraction and Damköhler number was employed. This PN model was verified against direction simulations. Then, a number of case studies were conducted, in order to illustrate the temporal evolutions of medium permeability and biomass content under different operating conditions. Finally, we explored the effects of biofilm morphology and permeability on biofilm growth, as well as non-unique relationship between medium permeability reduction and its porosity change.

show abstract

Hierarchical simulator of biofilm growth and dynamics in granular porous materials

Cited by 99 publications

References 71 publications

Biofilm streamers cause catastrophic disruption of flow with consequences for environmental and medical systems

Biofilm streamers cause catastrophic disruption of flow with consequences for environmental and medical systems

Studies on the effect of concentration of a self-inhibitory substrate on biofilm reaction rate under co-diffusion and counter-diffusion configurations

Pore-Network Modeling of Solute Transport and Biofilm Growth in Porous Media

Contact Info

Product

Resources

About