Evaluation of biofilm formation by L. monocytogenes and environmental microbiota isolated from tree fruit packing facilities

This study aimed to determine the effect of selected environmental microbiota on biofilm formation with L. monocytogenes. The microbiota under study included bacterial families previously shown to co-occur with L. monocytogenes in tree fruit packing facilities (i.e., Pseudomonadaceae, Xanthomonadaceae, Microbacteriaceae, and Flavobacteriaceae). Biofilm formation ability was measured in single- and multi-family assemblages. Bacterial strains from target families were isolated from the environmental microbiota of tree fruit packing facilities, and a total of 8, 8, 6, and 3 strains of Pseudomonadaceae, Xanthomonadaceae, Microbacteriaceae, and Flavobacteriaceae, respectively, were used in the experiments. The microbial composition of formed biofilms was characterized with amplicon sequencing of the 16S rRNA V4 gene region.