Biofilm-Forming Ability of <i>Microbacterium lacticum</i> and <i>Staphylococcus capitis</i> Considering Physicochemical and Topographical Surface Properties

• Main Authors: Elena Zand, Hedwig Pfanner, Konrad J. Domig, Gerhard Sinn, Marija Zunabovic-Pichler, Henry Jaeger
• Format: Article
• Language: English
• Published: MDPI AG 2021-03-01
• Series: Foods
• Subjects: biofilm; <i>Microbacterium lacticum</i>; food contact surface; stainless steel; hygienic design; roughness
• Online Access: https://www.mdpi.com/2304-8158/10/3/611

Biofilm characteristics of <i>Microbacterium lacticum</i> D84 (<i>M. lacticum</i>) and <i>Staphylococcus capitis</i> subsp. <i>capitis</i> (<i>S. capitis</i>) on polytetrafluoroethylene and AISI-304 stainless steel at early- (24, 48 h) and late-stage (144, 192 h) biofilm formation were investigated. <i>M. lacticum</i> biofilm structure was more developed compared to <i>S. capitis</i>, representing vastly mature biofilms with a strongly developed amorphous matrix, possibly extracellular polymeric substances (EPSs), at late-stage biofilm formation. <i>S. capitis</i> showed faster growth behavior but still resulted in a relatively flat biofilm structure. Strong correlations were found between several roughness parameters and <i>S. capitis</i> surface coverage (r ≥ 0.98), and between total surface free energy (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>γ</mi><mi>s</mi></msub></mrow></semantics></math></inline-formula>) and <i>S. capitis</i> surface coverage (r = 0.89), while <i>M. lacticum</i> remained mostly unaffected. The pronounced ubiquitous biofilm characteristics make <i>M. lacticum</i> D84 a suitable model for biofilm research. Studying biofilm formation of these bacteria may help one understand bacterial adhesion on interfaces and hence reduce biofilm formation in the food industry.