The influence of the different inductivity of acetyl phenyl–thiosemicarbazone–chitosan on antimicrobial activities

Ten different acetyl phenyl–thiosemicarbazone derivatives of chitosan were synthesized. Their structures were characterized by FT-IR and elemental analysis. The antimicrobial behaviors of CS and its derivatives against four species of bacteria and four crop-threatening pathogenic fungi were investigated in this paper. The results indicated that the antimicrobial activities of acetyl phenyl–thiosemicarbazone derivatives are much better than that of pure CS. The minimum value of MIC and MBC of the derivatives against Escherichia coli was 7.03 and 225 μg mL−1, respectively. All of the derivatives had significant inhibiting effect on the investigated fungi in the concentration of 50–500 μg mL−1, and the maximum inhibitory index was 93.10%. The bioactivities of the derivatives have relationship with the grafted groups with different inductivity.