Synthesis,Characterization, and Antibacterial Activity of Quaternized of N-Aromatic Chitosan Derivatives

Abstract

The quaternized of N-aryl chitosan (CTS) derivatives containing different aromatic moieties were synthesized by two steps, N-aromatic Schiff and the quaternization. The chemical structures of all chitosan derivatives, N-vanillin Schiff’s base chitosan (NVCh), N-cinnamaldehyde Schiff’s base chitosan (NCCh), N-benzaldehyde Schiff’s base CTS (NBCh), and their quaternized of N-aromatic CTS derivatives were characterized by ATR-FTIR. The water solubility of the N-aromatic Schiff’s base CTS derivatives had very poor water solubility. But after quaternized, the water solubility of CTS derivatives was obviously improved. The antibacterial studies of these CTS derivatives were carried out by the inhibition zone diameters methods against E.coli (Gram-negative), S.aurueus and P.aeruginosa (Gram-positive) bacteria, and against V.Aspergillus niger (fungal). It was found that the quaternized NVSCTS showed higher antibacterial activity than quaternized NCCh and quaternized NVBCh at the almost same DQ and ES level. In comparison to each of the chemical structure, it was found that the phenol hydroxyl group effect on antibacterial activity was even higher than that of positive charge density of CTS.