Biomedical Engineering and Bioengineering Commons^™

Characterization Of Biofilms In A Synthetic Rhizosphere Using Hollow Fiber Root-Mimetic Systems, Michelle Bonebrake

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The area around a plant’s roots hosts a complex and diverse microbial community. This environment can include a large number of bacteria that live on the surface of the root and benefit from the nutrients that the roots exude into the soil. These microbes can in turn be beneficial to the plant by protecting the roots from harmful fungi or stressful environmental conditions such as drought. In this thesis, several root-mimetic systems (RMSs) were developed for the study and growth of plant-beneficial bacteria in the laboratory environment. The RMS uses a porous hollow fiber used in hemodialysis as a surface …

Development And Optimization Of A Produced Water, Biofilm Based Microalgae Cultivation System For Biocrude Conversion With Hydrothermal Liquefaction, Benjamin L. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extraction of oil and gas in Utah’s Uintah Basin results in large quantities of wastewater, or produced water, with nutrients and residual organic chemical that represent a significant resource for producing energy-related and value-added products. Produced water was obtained as a biomass producing nutrient source from industries operating in Utah’s Uintah Basin. Within the Uintah Basin (defined as Uintah and Duchesne Counties within Utah) approximately 93 million barrels of water were produced in 2013 while only 11% of the water was disposed of through evaporation, with the national average at 2%. The rest is reinjected into the subsurface.

The goal …

Biofilms In Dental Unit Waterlines: Ultrastructural And Cytochemical Analysis, J. Barbeau, C. Avezard, E. Faucher, S. Zalzal, A. P. Prévost

Cells and Materials

Dental unit waterlines are heavily colonized by bacteria which contaminate the water used to perform intra-oral, and sometimes invasive, procedures. There is little information on the nature of the biofilm colonizing the flexible plastic tubing used to supply water to the different handpieces. We have therefore undertaken quantitative microbial analysis and ultrastructural studies of these biofilms by direct counting with the epifluorescent filter technique and by transmission and scanning electron microscopy after staining with ruthenium red and periodic acid-thiosemicarbazide-silver proteinate to visualize the composition and the distribution of exopolysaccharides and intracellular polysaccharides. The biofilm was revealed as a non-uniform structure …

Laboratory Growth Systems In Biofilm Research, Julian W. T. Wimpenny

Cells and Materials

The huge variety of ecosystems that we collectively refer to as "biofilm" is reflected by the numerous different systems available to grow them in the laboratory. The relationship between in situ systems, microcosms and laboratory models is defined and discussed. The first two represent holistic approaches designed to assess the structure and function of particular biofilms: the last is analytical and reductionist, aiming to isolate specific functions of biofilms in order to understand properties that can apply to biofilm in general. Properties of a model can be completely understood whilst this is unlikely with natural ecosystems because of the possibility …

Biofilm Mediated Calculus Formation In The Urinary Tract, Robert J. C. Mclean, David J. Stickler, J. Curtis Nickel

Cells and Materials

Mineralization and subsequent calculus formation is a common complication of biofilm infections. In the urinary tract, these infected calculi often arise from infections by urease-producing bacteria. Ammonia, liberated by bacterial urease activity, increases urine pH, resulting in the precipitation of Ca and Mg as carbonateapatite {Ca₁₀(PO₄,CO₃)₆(OH,CO₃)₂} and struvite (NH₄MgP0₄·6H₂O). These minerals become entrapped in the organic matrix which surrounds the infecting organisms and ultimately grow into mature calculi. When the causative organisms grow on urinary catheters and stents, the resulting mineralization can …