Study on the Antibacterial Effect of the New Anti-Biofilm Inhibitor ICAC on Escherichia coli

Yubin Bai¹Zixuan Shang^1,2Rongbin Hu¹Xun Gao¹Zhijin Zhang^1,2Bing Li¹Zhen Zhu^2*Jiyu Zhang^1*

• ¹Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, lanzhou, China
• ²Hebei University of Engineering, Handan, China

The rise of bacteria antibiotics resistance has bacome increasingly severe, and the development of natural compounds with antibacterial activity represents a promising approach to combat this issue. Isochlorogenic acid C (ICAC), a phenolic acid derived from plants, was investigated in this study fou its antibacterial and antibiofilm effects against E. coli, along with the underlying mechanisms. Results revealed that ICAC exhibited significant antibacterial and antibiofilm activity against E. coli. The antibiofilm activity of ICAC against E. coli was assessed using crystal violet (CV) staining, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The results demonstrated that ICAC could inhibit the biofilm formation of Escherichia coli, reduce the biomass of preformed biofilms, and decrease the production of extracellular polysaccharides (EPS) and extracellular proteins, as well as bacterial motility. Moreover, qRT-PCR results showed that ICAC downregulated genes associated with c-di-GMP synthesis while upregulating those involves in c-di-GMP degradation, thereby inhibiting biofilm formation and bacterial motility. In summary, ICAC shows potential as an effective anti-c-di-GMP agent and a novel antibacterial candidate for the treatment of E. coli infections.