Abstract:

N-(2-hydroxypropyl trimethylammonium chloride) chitosan (HTCC), N,N,N-trimethyl chitosan (TMC) and N-(sodium 2-hydroxypropylsulfonate) chitosan (HSCS) were synthesized and characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance spectra and elemental analysis. The antibacterial activity and anti-biofilm activity of quaternized chitosan with different structures (HTCC and TMC), and quaternized chitosan and sulfonated chitosan with similar structures (HTCC and HSCS) were compared. The experimental results showed that the antibacterial rate and biofilm removal rate of chitosan quaternary ammonium salt obtained by direct quaternization of chitosan (TMC) were better than those obtained by grafting quaternization of chitosan (HTCC). The antibacterial activity and antibiofilm activity of quaternized chitosan (HTCC) were better than those of sulfonated chitosan (HSCS). The antibacterial rates of TMC at 0.5mg/mL against E.coli and S.aureus were 93.0% and 100%, respectively. The biofilm inhibition rates of TMC at a half of minimal inhibitory concentration against E.coli and S.aureus were 51.4% and 41.5%, respectively. The biofilm removal rates of E.coli by TMC, HTCC and HSCS at 2.5mg/mL were 49.1%, 48.6% and 21.2%, respectively, and the biofilm removal rates of S.aureus were 85.1%, 82.7% and 81.8%, respectively.

Key words: chitosan quaternary ammonium salt, chitosan sulfonate, antibacterial, bacterial biofilm

摘要：

合成了N-(2-羟丙基-3-甲基氯化铵)壳聚糖（HTCC）、N,N,N-三甲基壳聚糖（TMC）和N-(2-羟丙基磺酸钠)壳聚糖（HSCS）。采用红外光谱、核磁共振氢谱、元素分析对产物的结构进行表征，分别比较不同结构的壳聚糖季铵盐（HTCC和TMC）以及相似结构的壳聚糖季铵盐和壳聚糖磺酸盐（HTCC和HSCS）的抗菌活性和抗生物被膜活性。实验结果发现，将壳聚糖的氨基直接季铵化得到的壳聚糖季铵盐（TMC）的抑菌率和生物被膜清除率要优于接枝季铵化得到的壳聚糖季铵盐（HTCC），季铵化壳聚糖（HTCC）的抗菌活性和抗生物被膜活性要优于磺化壳聚糖（HSCS）。0.5mg/mL的TMC对E. coli和S. aureus的抑菌率分别为93.0%和100%。TMC在$\frac{\mathrm{1}}{\mathrm{2}}$MIC浓度时对E. coli和S. aureus的生物被膜形成抑制率分别为51.4%和41.5%。2.5mg/mL的TMC、HTCC和HSCS对E. coli的生物被膜去除率分别为49.1%、48.6%和21.2%，对S. aureus的生物被膜的去除率分别为85.1%、82.7%和81.8%。

关键词: 壳聚糖季铵盐, 壳聚糖磺酸盐, 抗菌, 细菌生物被膜