The antibacterial activity and mechanism of imidazole chloride ionic liquids on Staphylococcus aureus

Yanhui Hu; Yuyuan Xing; Peng Ye; Haikuan Yu; Xianglei Meng; Yuting Song; Gongying Wang; Yanyan Diao

doi:10.3389/fmicb.2023.1109972

The antibacterial activity and mechanism of imidazole chloride ionic liquids on Staphylococcus aureus

Front Microbiol. 2023 Feb 6:14:1109972. doi: 10.3389/fmicb.2023.1109972. eCollection 2023.

Authors

Yanhui Hu^{1

2

3

4}, Yuyuan Xing^{2

3

4}, Peng Ye⁵, Haikuan Yu⁶, Xianglei Meng^{2

3}, Yuting Song^{2

3}, Gongying Wang^{1

3}, Yanyan Diao^{2

3

4}

Affiliations

¹ Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu, China.
² Beijing Key Laboratory of Ionic Liquids Clean Process, CAS Key Laboratory of Green Process and Engineering, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China.
³ University of Chinese Academy of Sciences, Beijing, China.
⁴ Innovation Academy for Green Manufacture, Chinese Academy of Sciences, Beijing, China.
⁵ Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, China.
⁶ Senior Department of Orthopedics, Chinese PLA Medical School, Beijing, China.

Abstract

Ionic liquids (ILs) have garnered increasing attention in the biomedical field due to their unique properties. Although significant research has been conducted in recent years, there is still a lack of understanding of the potential applications of ILs in the biomedical field and the underlying principles. To identify the antibacterial activity and mechanism of ILs on bacteria, we evaluated the antimicrobial potency of imidazole chloride ILs (C_nMIMCl) on Staphylococcus aureus (S. aureus). The toxicity of ILs was positively correlated to the length of the imidazolidinyl side chain. We selected C₁₂MIMCl to study the mechanism of S. aureus. Through the simultaneous change in the internal and external parts of S. aureus, C₁₂MIMCl caused the death of the bacteria. The production of large amounts of reactive oxygen species (ROS) within the internal parts stimulated oxidative stress, inhibited bacterial metabolism, and led to bacterial death. The external cell membrane could be destroyed, causing the cytoplasm to flow out and the whole cell to be fragmented. The antibacterial effect of C₁₂MIMCl on skin abscesses was further verified in vivo in mice.

Keywords: Staphylococcus aureus; antibacterial activity; ionic liquids; mechanism; skin abscess.

Grants and funding

This study was supported by the National Natural Science Foundation of China (21978292 and 21676280), the Innovation Academy for Green Manufacture, the Chinese Academy of Sciences (IAGM2020C20), the Major Program of the National Natural Science Foundation of China (21890762), and the International Partnership Program of the Chinese Academy of Sciences (grant no. 122111KYSB20190060).