Thymoquinone Inhibits Virulence Related Traits of ATCC 29544 and Has Anti-biofilm Formation Potential.

The aim of this study was to determine whether thymoquinone， the principal active ingredient in the volatile oil of seeds， could suppress certain virulence traits of ATCC 29544 which contribute to infection. Sub-inhibitory concentrations of thymoquinone significantly decreased motility， quorum sensing， and endotoxin production of ATCC 29544 and biofilm formation of 7-17. Thymoquinone substantially reduced the adhesion and invasion of ATCC 29544 to HT-29 cells and decreased the number of intracellular bacterial cells within the RAW 264.7 macrophage cells. Thymoquinone also repressed the transcription of sixteen genes involved in the virulence. These findings suggest that thymoquinone could attenuated virulence-related traits of ATCC 29544， and its effects on other strains and infection need further investigation.