Table 5.
Antibacterial activity of chitosan oligomers (COS), H. syriacus flower and leaf hydromethanolic extracts, their main constituents (heptacosanol, DHTMC, and vitamin E), and their corresponding conjugate complexes (COS–flower extract, COS–leaf extract, COS–heptacosanol, COS–DHTMC, and COS–vitamin E) against the two phytopathogenic bacteria under study at different concentrations (expressed in μg·mL−1).
| Pathogen | Compound | Concentration (μg·mL−1) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 62.5 | 93.75 | 125 | 187.5 | 250 | 375 | 500 | 750 | 1000 | 1500 | ||
| E. amylovora | COS | + | + | + | + | + | + | + | + | + | − |
| Flower extract | + | + | + | + | + | + | + | − | − | − | |
| Leaf extract | + | + | + | + | + | + | + | + | − | − | |
| Heptacosanol | + | + | + | + | + | + | + | + | + | − | |
| DHTMC | + | + | + | + | + | + | + | + | − | − | |
| Vitamin E | + | + | + | + | + | + | + | − | − | − | |
| COS–Flower extract | + | + | + | + | + | + | − | − | − | − | |
| COS–Leaf extract | + | + | + | + | + | − | − | − | − | − | |
| COS–Heptacosanol | + | + | + | + | + | + | + | + | − | − | |
| COS–DHTMC | + | + | + | + | + | + | − | − | − | − | |
| COS–Vitamin E | + | + | + | + | - | - | - | - | - | - | |
| E. vitivora | COS | + | + | + | + | + | + | + | + | + | − |
| Flower extract | + | + | + | + | + | + | − | − | − | − | |
| Leaf extract | + | + | + | + | + | + | + | + | + | − | |
| Heptacosanol | + | + | + | + | + | + | − | − | − | − | |
| DHTMC | + | + | + | + | + | + | + | − | − | − | |
| Vitamin E | + | + | + | + | + | + | − | − | − | − | |
| COS–Flower extract | + | + | + | + | − | − | − | − | − | − | |
| COS–Leaf extract | + | + | + | + | + | + | − | − | − | − | |
| COS–Heptacosanol | + | + | + | − | − | − | − | − | − | − | |
| COS–DHTMC | + | + | + | − | − | − | − | − | − | − | |
| COS–Vitamin E | + | + | + | + | - | - | - | - | - | - | |
DHTMC = 3,4-dihydro-4,4,6,8-tetramethyl-coumarin.