AUTHOR=Mu Yongqi , Zeng Hong , Chen Wei 

TITLE=Quercetin Inhibits Biofilm Formation by Decreasing the Production of EPS and Altering the Composition of EPS in Staphylococcus epidermidis

JOURNAL=Frontiers in Microbiology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.631058

DOI=10.3389/fmicb.2021.631058

ISSN=1664-302X

ABSTRACT=<p><italic>Staphylococcus epidermidis</italic> is an opportunistic pathogen, and its biofilm formation ability is an important virulent factor. Quercetin, a typical flavonoid ubiquitously used in dietary supplementation, is known for its antioxidant property, but its anti-biofilm activity against <italic>S. epidermidis</italic> remains unknown. In this study, the anti-biofilm activity of quercetin was investigated using <italic>S. epidermidis</italic> ATCC35984, a strong biofilm-positive strain. An attempt was made to disclose the mechanisms of the anti-biofilm activity of quercetin. <italic>S. epidermidis</italic> exhibited a less cell surface hydrophobicity after quercetin treatment. Also, quercetin effectively inhibited <italic>S. epidermidis</italic> cells from adhering to the glass slides. Quercetin downregulated the intercellular adhesion (<italic>ica</italic>) locus and then polysaccharide intercellular adhesin (PIA) production was reduced. Therefore, <italic>S. epidermidis</italic> cells became less hydrophobic, which supported quercetin’s anti-biofilm effect. Our study suggests that quercetin from plants be given further attention as a potential anti-biofilm agent against the biofilm formation of <italic>S. epidermidis</italic>, even biofilm infections of other bacteria.</p>