Thymol combined with SAEW for the eradication of mature biofilms and reduction of bacterial virulence.

INTRODUCTION

Biofilms formed by () are a major challenge in clinical settings due to their resilience and contribution to persistent infections, especially in patients with indwelling medical devices. There is an urgent need for effective strategies to disrupt mature biofilms and control associated infections.

METHODS

This study investigated the combined antibacterial activity and mature biofilm eradication efficacy of slightly acidic electrolyzed water (SAEW) and thymol against PAO1 through mature biofilm removal assays. The underlying antibacterial mechanism was explored by measuring intracellular reactive oxygen species (ROS) levels. The impact of the combined treatment on the expression of PAO1 virulence genes was assessed using RT-qPCR. Additionally, the safety of the combination was evaluated through acute dermal toxicity and ocular irritation tests in mice.

RESULTS

The combination of thymol and SAEW effectively disrupted mature biofilms, significantly reduced bacterial load on medical catheters, and enhanced ROS production. Furthermore, the treatment downregulated key virulence genes, and , which are critical for elastin degradation and pathogenicity. Safety assessments confirmed no acute skin or ocular toxicity, indicating its suitability for clinical applications.

DISCUSSION

Thymol-enhanced SAEW shows great potential as a safe and effective strategy for biofilm eradication and infection control, paving the way for innovative approaches to combat antimicrobial-resistant pathogens in healthcare settings.