Insights into coumarin-mediated inhibition of biofilm formation in Salmonella Typhimurium

Abstract

Coumarins have been shown to possess antimicrobial, anti-quorum sensing and anti-biofilm properties against a wide range of pathogenic bacteria. This study aimed to shed light on the effects of non-substituted coumarin on biofilm formation by the foodborne pathogen Salmonella Typhimurium. Additionally, its efficacy was tested in combination with another potent anti-biofilm agent, resveratrol. Coumarin inhibited biofilm formation for prolonged periods in millimolar concentrations with marginal effects on planktonic growth. It attenuated curli and cellulose production, likely by downregulating the transcript levels of major biofilm formation genes csgD, csgA and adrA. Coumarin further restricted motility in a dose-dependent manner. In addition, coumarin with resveratrol exhibited improved anti-biofilm properties compared with the individual compounds alone. Thus, coumarin alone or with resveratrol can be employed for inhibiting biofilms in food storage and processing units.

Keywords:

• Salmonella Typhimurium
• biofilm
• motility
• coumarin
• resveratrol

Acknowledgements

The authors would like to thank Supriya Rananaware, Sanmoy Pathak, Taru Verma and other members of the DpN lab for their valuable suggestions and support during the study.

Disclosure statement

The authors declare no conflict of interests.

Additional information

Funding

The study was funded by Department of Biotechnology, Governemnt of India - Indian Institue of Science partnership program.