title: Synthesis and characterization of chitosan derivatives with dual-antibacterial functional groups.
abstract: With the aim to discover chitosan derivatives with enhanced antibacterial activity and good water solubility compared with natural chitosan, a novel O-quaternary ammonium N-acyl thiourea chitosan (OQCATUCS) bearing double antibacterial groups with different degrees of substitution has been synthesized. The derivative was characterized by FTIR, (13)C NMR, elemental analysis, XRD, TGA and zeta potential analysis. Water solubility was also investigated. The antimicrobial activities of chitosan and its derivatives were investigated by assessing the mortality rates of Staphyloccocus aureus, Escherichia coli, Aspergillus niger, Pseudomonas aeruginosa and Bacillus subtilis. The order of antibacterial activities was O-quaternary ammonium N-acyl thiourea chitosan (OQCATUCS)>O-quaternary ammonium chitosan (OQCS)>chitosan (CS). The zeta potential and antibacterial results indicated that the introduced quaternary ammonium and thiourea groups increased the positive charge of chitosan derivative, thereby enhanced its antibacterial activity. The mechanism of chitosan derivatives against E. coli and S. aureus was evaluated via analyzing integrity of cell membranes and transmission electron microscopy data. These results demonstrated that OQCATUCS killed the bacteria via disrupting the cell membrane.
authors: State Key Laboratory of Pulp & Paper Engineering, South China University of Technology, Guangzhou 510640, China.
authors: Zhihan
authors: Z
authors: Li
authors: State Key Laboratory of Pulp & Paper Engineering, South China University of Technology, Guangzhou 510640, China.
authors: Fei
authors: F
authors: Yang
authors: State Key Laboratory of Pulp & Paper Engineering, South China University of Technology, Guangzhou 510640, China. Electronic address: rdyang@scut.edu.cn.
authors: Rendang
authors: R
authors: Yang
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000648:ultrastructure; D066241:Carbon-13 Magnetic Resonance Spectroscopy; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D048271:Chitosan / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D005658:Fungi / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D008826:Microbial Sensitivity Tests; D000644:Quaternary Ammonium Compounds / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D055672:Static Electricity; D013818:Thermogravimetry; D013890:Thiourea / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D014867:Water; D014961:X-Ray Diffraction
chemical_list: D000900:Anti-Bacterial Agents; D000644:Quaternary Ammonium Compounds; D014867:Water; D048271:Chitosan; D013890:Thiourea
keywords: Antibacterial activity; Double antibacterial groups; O-Quaternary ammonium N-acyl thiourea chitosan