N,N-dimethyl chitosan oligosaccharide (DMCOS) promotes antifungal activity by causing mitochondrial damage

By modifying chitosan oligosaccharide (COS) with the Eschweiler-Clarke reaction, the chitosan oligosaccharide derivative DMCOS was synthesized. FT-IR, 1D and 2D NMR spectra, MALDI-ToF MS, and elemental analysis were applied to analyze the structure of DMCOS, which revealed that the primary amines were converted into tertiary amines after methylation. DMCOS displayed less thermal stability than COS. In comparison to COS, it was discovered that DMCOS possessed more potent antimicrobial activity against four bacterial strains (Staphylo-coccus aureus, methicillin-resistant Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa) and three yeast strains (Candida albicans, Candida tropicalis, and Candida parapsilosis). The antioxidant studies indicated that DMCOS had less antioxidant activity than COS. Consequently, ROS level elevated in C. albicans cells following treatment with DMCOS, which decreased mitochondrial membrane potential. It was recalled that DMCOS may kill C. albicans by causing mitochondrial damage. In addition, DMCOS was demonstrated to be non-cytotoxic.

Automated summary

By modifying chitosan oligosaccharide (COS) with the Eschweiler-Clarke reaction, a derivative called DMCOS was synthesized. Analysis revealed that DMCOS had converted primary amines into tertiary amines after methylation. DMCOS showed less thermal stability than COS, but exhibited stronger antimicrobial activity against bacterial and yeast strains, while also displaying lower antioxidant activity and causing mitochondrial damage in C. albicans cells.