Biofilm matrix

About: Biofilm matrix is a research topic. Over the lifetime, 1589 publications have been published within this topic receiving 110140 citations.

A new tool to attack biofilms: driving magnetic iron-oxide nanoparticles to disrupt the matrix

Abstract: A main feature of biofilms is the self-produced extracellular polymeric substances (EPSs) that act as a protective shield, preventing biocide penetration. We use magnetic iron oxide nanoparticles (MNPs) in combination with magnetic fields to damage the biofilm matrix and cause detachment. A Methicillin-resistant Staphylococcus aureus (MRSA) biofilm strain is used to demonstrate the efficacy of the methodology with different sizes and concentrations of MNPs under AC and DC applied field conditions. We achieve up to a nearly 5 log10 reduction in biofilm bacteria after treatment with 30 mg mL-1 of 11 nm MNPs using a magnetic field. The MNPs cause significant mechanical disruption to the matrix and lead to biofilm dispersal. In addition, using magnetic hyperthermia further affects biofilm damage.

Extracellular polymeric substances in microbial biofilms

Abstract: Publisher Summary A definition of microbial biofilms systems may be based on biofilm structure or on biofilm function. Structurally defined, biofilm systems are microorganisms and their extracellular polymeric substances associated with an interface. In this definition, microorganisms, are understood in the broadest sense including bacteria, Archaea, as well as eukaryotic microorganisms, i.e., protozoa, algae, and fungi. The term “interfaces” does include any possible type: liquid–liquid, solid–liquid, gas–liquid, or solid–gas. As a major component of biofilm systems, the extracellular polymeric substances produced by the members in a specific biofilm system are explicitly included in this definition. Functionally defined, biofilms are spatially structured communities of microbes whose function is dependent upon a complex web of symbiotic interactions. Apart from cellular constituents, a second major component of biofilm systems is represented by the polymer matrix. The extracellular polymeric substances (EPS) of the biofilm matrix appear to have several key properties and functions. In this chapter, the nature of biofilm and EPS is discussed, and a survey of the main literature on the biofilm matrix is provided. The chapter introduces a novel concept on EPS functionality to elaborate on EPS functions, to raise the discussion on biofilm EPS, to implement further studies using different biofilm systems, and to trigger new approaches and hypotheses.

Curcumin Quantum Dots Mediated Degradation of Bacterial Biofilms.

Abstract: Bacterial biofilm has been reported to be associated with more than 80 percent of bacterial infections. Curcumin, a hydrophobic polyphenol compound, has anti-quorum sensing activity apart from having anti-microbial action. However, its use is limited by its poor aqueous solubility and rapid degradation. In this study, we attempted to prepare quantum dots of the drug curcumin in order to achieve enhanced solubility and stability and investigated for its antimicrobial and antibiofilm activity. We utilized a newer two-step bottom up wet milling approach to prepare Curcumin Quantum Dots (CurQDs) using acetone as a primary solvent. Minimum inhibitory concentration against select gram-positive and gram-negative bacteria was performed. The antibiofilm assay was performed at first using 96-well tissue culture plate and subsequently validated by Confocal Laser Scanning Microscopy. Further, biofilm matrix protein was isolated using formaldehyde sludge and TCA/Acetone precipitation method. Protein extracted was incubated with varying concentration of Curcumin quantum dots for 4 hrs and was subjected to SDS-PAGE. Molecular docking study was performed to observe interaction between curcumin and phenol soluble modulins as well as curli proteins. The biophysical evidences obtained from TEM, SEM, UV-VIS, fluorescence, Raman spectroscopy and zeta potential analysis confirmed the formation of curcumin quantum dots with increased stability and solubility. The MICs of curcumin quantum dots, as observed against both select gram positive and negative bacterial isolates, was observed to be significantly lower than native curcumin particles. On TCP assay, Curcumin observed to be having antibiofilm as well as biofilm degrading activity. Results of SDS-PAGE and molecular docking have shown interaction between biofilm matrix proteins and curcumin. The results indicate that aqueous solubility and stability of Curcumin can be achieved by preparing its quantum dots. The study also demonstrates that by sizing down the particle size has not only enhanced its antimicrobial properties but it has also shown its antibiofilm activities. Further, study is needed to elucidate the exact nature of interaction between curcumin and biofilm matrix proteins.