Antibacterial Activity of N,O-Acylated Chitosan Derivative

Abstract

The antibacterial activity of <i>N</i>,<i>O</i>-acylated chitosan derivative with linoleic acid (CH_LA) was tested by disc and well diffusion, agar impregnation and microdilution methods against <i>Staphylococcus aureus</i>, <i>Escherichia coli</i> and <i>Helicobacter pylori</i> strains. Hydrophobically modified chitosan (HMC) was expected to exhibit enhanced antibacterial activity and specific mucin interactions. Although diffusion tests have not indicated the antibacterial potential of chitosan (CH) or CH_LA, the results of the microdilution method demonstrated that tested polymers significantly reduced the amount of living bacteria cells in different concentrations depending on the microorganism. Additionally, CH_LA was characterized by enhanced antibacterial activity compared to CH, which may suggest a different mechanism of interaction with <i>S. aureus</i> and <i>H. pylori</i>. Furthermore, the UV-VIS analysis revealed that the amphiphilic character of derivative led to strong CH_LA-mucin interactions. The study proved the high potential of CH_LA in antibacterial applications, especially for the gastrointestinal tract.