BIOFILM FORMATION POWER OF ESCHERICHIA COLI IN DAIRY FARMS

Biofilm formation is considered an important virulence factor of opportunistic and pathogenic bacteria. Bacterial biofilms can grow on many abiotic and biotic surfaces. Biofilm-related diseases caused by gram-positive bacteria can cause many conditions such as gingivitis, endocarditis and prostatitis. The aim of this study was to evaluate the presence of Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes in milking machines, given their potential to contaminate milk during the milking process. Additionally, the study assessed the ability of these bacteria to form biofilms, which can further affect milk quality and safety. In the present study, samples were collected from a total of ten different dairy farms in Gaziantep, Turkey, and the Campania region of Southern Italy, four hours after the cleaning and sanitation process. Samples were collected through sponges from both the surfaces and internal components of the milking machines. The classical culture method combined with MALDI-TOF mass spectrometry was used to isolate and identify the bacteria. Subsequently, the isolated bacteria were evaluated for their biofilm formation ability using the microtiter plate method. According to the isolation results, Enterobacteriaceae and Staphylococcus spp. counts varied between 2.0 - 6.0 log10 cfu/ml; 2.0 - 6.60 log10 cfu/ml, respectively. Among the 132 isolates for both regions was determined only one E. coli. L. monocytogenes and S. aureus weren’t isolated from the samples. It was determined that E. coli, with an ODs/ODc value of 13.67, was a strong biofilm former. In light of the results, it is thought that E. coli, which has strong biofilm properties, threatens public health by contaminating products in dairy industry.