Development of bacterial biofilms using E.coli and P.aeruginosa

Biofilm bacteria existence in both natural and artificial surfaces is becoming increasingly evident. Biofilms are complex group of microorganisms, able to adapt and survive in a new environment provided there is an availability of nutrient, adequate incubation time and an appropriate media. The bacterial strains of Escherichia coli and Pseudomonas aeruginosa were used to develop biofilms in the laboratory. These bacterial strains were observed using Gram stain, Catalase test and Oxidase test. These bacterial strains were enumerated for viable colony units at 0, 2, 4, 6 and 8 hours and incubated at 30°C and 37°C respectively. Bacterial strains grown to stationary phase were inoculated into 96-well microtitre plate at 0, 2, 4, 6 and 8 hours incubated at 30°C and 37°C respectively, stained with crystal violet, followed by optical density measurement at 540nm. Result showed that E. coli and P. aeruginosa are Gram-negative facultative anaerobes, biofilms and viable CPU were obtained from both bacterial strains. The absorbance of adherent cells of the bacterial strains of E. coli and P. aeruginosa increased as the time increased from 0 to 6 hours and decreased at 8 hours respectively.