Anti-bacterial Susceptibility and Biofilm-Forming Ability of Foodborne Pathogens Isolated from Minimally Processed Fruits and Vegetables Obtained from Markets in Southeastern Nigeria.

The resistance of foodborne pathogens to antibiotics and their ability to form biofilms poses a serious public health burden globally. This study investigated the antibacterial susceptibility pattern and biofilm-forming ability of bacterial isolates from surfaces of minimally processed fruits and vegetables from markets in Southeastern Nigeria. Randomly selected samples of fresh minimally processed watermelon, cucumber, and garden egg were collected and evaluated by standard plate techniques. Pure cultures were identified macroscopically, microscopically, and using biochemical analysis. The antibiotic susceptibility studies were conducted using the Kirby-Bauer disk diffusion method on eleven antibiotic discs. The biofilm screening was conducted using Congo Red Agar medium and scanning electron microscopy (SEM) was to determine morphological features of biofilm formers. Characterization revealed seventeen probable species of pathogenic bacteria. Antibiotic susceptibility results revealed MTX50 having the least antibacterial activity with percentage susceptibility of 0 and AMP10, the most effective antibiotic on all isolates with percentage susceptibility of 70.41.Salmonella sp. had a mean IZD of 18.67 mm to PEF5 and according to CLSI guidelines, it is said to be resistant to PEF5.All isolates were strong biofilm formers except four which were non- and moderate biofilm formers. SEM micrograph revealed organisms enclosed in an extracellular matrix. The detection of these opportunistic pathogens capable of forming biofilms in freshly minimally processed fruits and vegetable poses a serious risk for consumers because of their bacteria colonization indication ratio and resistance patterns which varied in response to the various antibiotics used. Biofilm formers indicate resistant pathogens as they formed extracellular polymeric matrices. [ABSTRACT FROM AUTHOR]