Table 1.
Effect of pH on the antibacterial activity of the water-soluble chitosan derivatives in nutrient broth.
| Water-soluble | Antibacterial activity (%) ** | |||||
|---|---|---|---|---|---|---|
| chitosan | S. aureus | L. monocytogenes | B. cereus | E. coli | S. dysenteriae | S. tphimurium |
| derivative * | ||||||
| pH 5.0 | ||||||
| GN50-5 | 100 ± 0 | 100 ± 0 | 100 ± 0 | 100 ± 0 | >99 ± 0 | >99 ± 0 |
| GN70-3 | 100 ± 0 | 100 ± 0 | 100 ± 0 | 100 ± 0 | 100 ± 0 | >100 ± 0 |
| Chitosan | >99 ± 0 | >99 ± 0 | 90 ± 0 | >99 ± 0 | >99 ± 0 | >99 ± 0 |
| pH 7.0 | ||||||
| GN50-5 | 100 ± 0 | >99 ± 0 | >99 ± 0 | >99 ± 0 | >99 ± 0 | >99 ± 0 |
| GN70-3 | 100 ± 0 | >99 ± 0 | >99 ± 0 | >99 ± 0 | >99 ± 0 | >99 ± 0 |
| Chitosan | 14 ± 2 | 11 ± 5 | 4 ± 2 | 11 ± 5 | 5 ± 2 | 4 ± 1 |
* Add 250 mg/L concentration of chitosan or water-soluble chitosan derivatives into nutrient broth. ** Each value is expressed as mean ± standard deviation (n = 3).