Resistance to disinfectants and antibiotics of Pseudomonas spp. and Listeria spp. biofilms on polystyrene and stainless steel

The capacity of Pseudomonas spp. and Listeria spp. isolates in forming polystyrene and stainless steel biofilms was assessed and their resistance to disinfectants and antibiotics agents was verified. Isolates originated from chicken and buffalo meat cuts in abattoirs and retail outlets in the southern region of the state of Rio Grande do Sul, Brazil. Isolates which formed stainless steel biofilm were tested with regard to the activities of the disinfectant agents organic chlorine and ammonium quaternary. Isolates of L. monocytogenes formed polystyrene and stainless steel biofilm. Further, 32 and 72% of Pseudomonas spp. isolates respectively formed polystyrene and stainless steel biofilm. The disinfectant agent ammonium quaternary was more efficient than organic chlorine in the decrease of biofilms on stainless steel surfaces for Listeria isolates. Multi-resistance to antibiotics was high for Listeria spp. (94.7%) and Pseudomonas spp (84%). From these results, isolates from chicken and buffalo meat cuts were developers of biofilm on polystyrene and stainless steel, and resistants’ to antibiotics, putting at risk consumers´ health.