Abstract: Biofilm formation of Salmonella sp. (AS 1.1552) on stainless steel surface were observed with scanning electronic microscope (SEM) and measured through its growth curve. The results showed that Salmonella sp. biofilm on stainless steel surface entered the stationary phase after 8 h incubation and the cell density was 3×10⁶ cfu·cm^-2. The bacterial cells on the biofilm had higher resistance to chlorine dioxide than those in suspension. Tryptone soy broth (TSB) obviously reduced the sterilization effect of chloride dioxide．

Key words: Salmonella sp., biofilm, chlorine dioxide, scanning electronic microscope