Abstract

The effect of high pressure carbon dioxide (HPCD) on Staphylococcus aureus biofilm was studied in detail. The parameters of HPCD such as pressure, temperature and holding time were investigated and optimized by response surface methodology (RSM). A second order equation was established based on the RSM results. It was also found that HPCD could remove S. aureus biofilm to some extent but not significantly, and the effect increased with pressure increase. The microstructures of treated S. aureus biofilm were observed by scanning electron microscopy (SEM). The results showed that the entire morphology of biofilm was changed greatly, while the single cell structure was not. HPCD was confirmed to have strong inactivation ability for S. aureus biofilm. It has great potential on biofilm control in medical and food industry.

Key words: Staphylococcus aureus, biofilm, high pressure carbon dioxide, inactivation.