Screening of Biosurfactant Production by Yarrowia lipolytica Strains and Evaluation of Their Antibiofilm and Anti-Adhesive Activities against Salmonellaenterica ser. Enteritidis Biofilms

A yeast strain (TY24) isolated from a soil sample, and a previously characterized Y. lipolytica TEM OS12 strain were screened for their ability to produce biosurfactants. Positive results were revealed for both strains on CTAB-MB agar plates, by the drop collapse method, parafilm M Test, and oil displacement method. The yeast isolate TY24 and Y. lipolytica TEM OS12 also produced lipases, demonstrated β-hemolytic activity, and decreased the surface tension from 57.5 to 33.5 and 35.5 (mN m –1 ), respectively. The newly isolated strain was identified as Y. lipolytica TY24 using ITS1-5.8S rRNA-ITS2 and D1/D2 domain of 26S rRNA regions. Co-incubation of Salmonella enterica ser. Enteritidis with increasing volumes of biosurfactant-containing supernatants from the cultures of Y. lipolytica TEM OS12 and Y. lipolytica TY24 prevented biofilm formation by 89.42 and 88.09%, respectively. The biosurfactant-containing CFS produced by the tested yeast strains inhibited S. Enteritidis biofilms efficiently.