The objectives of this study were to evaluate the antimicrobial resistance and the
biofilm-producing
ability of
Salmonella sp.
strains isolated from frozen
poultry carcasses. Antimicrobial susceptibility was tested by the disk-
diffusion method.
Biofilm-producing
ability was determined in 96-well
polystyrene microplates stained with
crystal violet at 1%. Out of the 22
strains tested, all were multiresistant, that is, resistant to more than three antimicrobial classes, and 72.7% were able to form
biofilms. The highest resistance rates obtained were against
sulfonamides,
tetracycline, and
quinolones. On the other
hand, 100% of the
strains were sensitive to
chloramphenicol. According to the rate of
biofilm formation, 3 (13.6%) and 13 (59.1%)
strains were classified as moderate and weak
biofilm-producers, respectively, and 27.3% did not form
biofilms.
Biofilms increase the tolerance of microorganisms to stress, reducing their
sensitivity to
disinfectants and antimicrobials; favor
equipment corrosion; and act as
substrates for the adhesion of
bacteria with lower
biofilm-producing capacity. The results of the present study stress the importance of cleaning
procedures in
food processing plants and highlight the
public health risks related to the emergence of multiresistant
strains.(AU)