Chitosan is a kind of biopolymer with good adsorption, film formation, permeability, fibrillation, hygroscopicity and moisture retention. However, due to its crystallinity, it can only be dissolved in some dilute inorganic or organic acids and cannot be directly dissolved in water, which limits its application to a large extent. Therefore, the research of water-soluble chitosan and its derivatives has become a direction of attention. Yang Sheng et al. studied the inhibitory effect of water-soluble chitosan on several common bacteria.
Experiment with self-made water-soluble chitosan (DD.85.3%, particle size 100 mesh, viscosity 30mPa•s), using distilled water and 1% HAc as solvents, and the concentration of dilution method is 0.5%, 0.25%, 0.125%, 0.0625%, 0.03125% water-soluble chitosan solution, using solid medium in vitro antibacterial method to determine the antibacterial effect of water-soluble chitosan on Escherichia coli, Staphylococcus aureus, Proteus, Candida albicans, Pseudomonas aeruginosa. The test results show that the antibacterial activity of water-soluble chitosan in 1% HAc is stronger than the antibacterial activity in water (see Table 1 and 2). Among the 5 tested bacteria, its antibacterial activity against Staphylococcus aureus and large intestine Bacillus has the strongest inhibitory effect (see Table 3).
Inhibition zone of water-soluble chitosan on each tested bacteria when dissolved in water
The inhibitory rate of different concentrations of water-soluble chitosan dissolved in 1% HAc to each tested bacteria