title: Microbial adhesion capacity. Influence of shear and temperature stress.
abstract: Environmental parameters dictate the conditions for both biofilm formation and deconstruction. The aim of this study is to analyse the impact of hydrodynamic and thermodynamic effects on bacterial detachment. Escherichia coli grown on two stainless steel metal surfaces with different roughness (brushed with roughness of 0.05 μm and electropolished with roughness of 0.29 μm) are exposed to laminar and turbulent (shower) flows of phosphate buffered saline media at temperatures of 8, 20 and 37 °C. Results show that the turbulent flow removes significantly more bacterial cells than laminar flow (p <0.05) on both materials. This indicates that the shear force determines the rate of detached bacteria. It is also observed that detachment of cells is more efficient on brushed than on electropolished contact surfaces because on the latter surface, fewer cells were attached before exposure. Moreover, we demonstrate that the temperature of the washing agent has an impact on bacterial detachment. At the same flow conditions, the exposure to higher temperature results in greater detachment rate.
authors.affiliation: a Faculty of Health Sciences , University of Ljubljana , Ljubljana , Slovenia.
authors.forename: Rok
authors.initials: R
authors.lastname: Fink
authors.affiliation: a Faculty of Health Sciences , University of Ljubljana , Ljubljana , Slovenia.
authors.forename: Martina
authors.initials: M
authors.lastname: Oder
authors.affiliation: b Iskra Pio d.o.o. , Šentjernej , Slovenia.
authors.forename: Dušan
authors.initials: D
authors.lastname: Rangus
authors.affiliation: c Faculty of Health Sciences , University of Primorska , Izola , Slovenia.
authors.forename: Peter
authors.initials: P
authors.lastname: Raspor
authors.affiliation: a Faculty of Health Sciences , University of Ljubljana , Ljubljana , Slovenia.
authors.forename: Klemen
authors.initials: K
authors.lastname: Bohinc
mesh_terms: D001422:Bacterial Adhesion; D018441:Biofilms; D004926:Escherichia coli / Q000502:physiology*; D057446:Hydrodynamics; D013193:Stainless Steel / Q000032:analysis*; D013499:Surface Properties; D013696:Temperature; D013816:Thermodynamics
chemical_list: D013193:Stainless Steel
keywords: adhesion; laminar flow; shear stress; temperature stress; turbulent flow