Detachment of adhered enteropathogenic Escherichia coli cells from polythene fragments immersed in aquatic microcosm using Eucalyptus microcorys extract (Myrtaceae)
Résumé
This study aimed to assess the effect of the concentration of an aqueous extract of Eucalyptus microcorys on the detachment of enteropathogenic E. coli cells previously adhered on polythene surface. The results showed that the extract causes a detachment of cells adhered and the importance of detachment depends on incubation duration of substrate in the plant extract solution. The higher value of detached cell abundance, after 3 hours duration of cell adhesion process (DCAP), was 8.72 (Ln (CFU/cm 2)) and the percentage of detached cells reached value of 11.2% when the bacteria cells were harvested from the lag growth phase. For cells coming from exponential growth phase, after 9h of DCAP, the abundance of cells detached reached value of 8.95 (Ln (CFU/cm 2)) and the higher percentage of detached cells was 68.8%. The values of 48.5% and 55.6% were noted when cells harvested from stationary and decline growth phases respectively. The cell detachment process observed could be due to the presence of some secondary metabolites such as flavonoids, triterpenoids, alkaloids, tannins which can disrupt physicochemical characteristics of bacteria surface. They seem to have a significant impact on exopolysaccharids matrix secreted by bacteria during the cell adhesion process. An overall significant difference (P<0.01) was observed between the mean abundances of detached cells for each extract concentrations at different growth stages.
Origine | Fichiers éditeurs autorisés sur une archive ouverte |
---|
Loading...