Investigation of Nutrients as Treatments of Bacterial Biofilms
Abstract
Using nutrients bacteria utilize to grow as treatments of bacterial biofilms have been investigated. This dissertation examines the problem of the prevention and treatment of biofilms by: (i) testing the effect of the nutrient β-phenylethylamine (PEA) on growth, ATP content of biofilm, and biofilm biomass, (ii) testing the effect of ethyl acetoacetate (EAA) and other small molecules on growth, ATP content of biofilm, and biofilm biomass, and (iii) investigating three applications of PEA and EAA. PEA could be used as both, prevention and treatment for bacterial biofilms. We observed a reduction of growth, ATP content of biofilm, and biofilm biomass of Escherichia coli K-12 AJW678 with increasing concentrations regardless of when PEA was added. PEA and EAA were able to reduce growth, ATP content of biofilm, and biofilm biomass for multiple bacterial strains, but the efficacy of the nutrients were strain dependent. PEA was found to effectively reduce growth, ATP content of biofilm, and biofilm biomass when used in multiple applications. When PEA was physically integrated in polyurethane, we observed at least a 20 % reduction of ATP content of biofilm for all the bacterial strain tested. To mimic a clinically relevant environment, biofilms were formed in silicone tubing and treatment of PEA and EAA were administered similar to antibiotic lock treatments (ALT). The PEA and EAA treatments reduced ATP content and biofilm biomass of multiple pathogens. PEA was also effective on ATP content, biofilm biomass, and cell counts when used in a microfluidic system.