In vitro anti-biofilm efficacy of sanguinarine against carbapenem-resistant Serratia marcescens

Abstract

Sanguinarine, a plant-derived benzophenanthridine alkaloid, was studied in terms of its anti-biofilm effects against carbapenem-resistant Serratia marcescens (CRSM). Minimum inhibitory concentrations (MICs) and cell membrane integrity were measured to investigate the antimicrobial mechanism of sanguinarine. Additionally, the extent of biofilm formation by CRSM exposed to sanguinarine was measured by crystal violet staining and visualized via field emission scanning electron microscopy and confocal laser scanning microscopy. Sanguinarine displayed moderate activity against CRSM, with a MIC₉₀ of 32 μg ml⁻¹. Moreover, cell membrane integrity was severely disrupted by sanguinarine at 64 μg ml⁻¹, and biofilm formation was sharply inhibited at 32 μg ml⁻¹. The minimum biofilm eradication concentration was 512 μg ml⁻¹ against mature CRSM biofilms. The overall results suggest that sanguinarine is a potential anti-biofilm agent that can be explored to treat CRSM infections.

Keywords:

• Sanguinarine
• carbapenem-resistant Serratia marcescens
• antimicrobial
• antibiofilm

Disclosure statement

The authors declare that they have no competing interests.

Additional information

Funding

This work was supported in part by the Science and technology plan project of the Xi’an science and technology bureau (2020KJRC0007), the Xi’an Weiyang District Science and technology project (201926), and the China Postdoctoral Science Foundation (2019M653945).