Anti-attachment, anti-biofilm, and antioxidant properties of Brassicaceae extracts on Escherichia coli O157:H7

Bacteria can survive and persist in food processing environments by attachment and biofilm formation and transfer to food products, causing serious foodborne illness. In this study, we investigated natural substances that belong to the family Brassicaceae to determine whether they have potential anti-attachment activities against Escherichia coli O157:H7. The inhibition of biofilm formation was evaluated by crystal violet and resazurin assays at different stages of biofilm formation (initial attachment, biofilm formation, and after biofilm development) of E. coli O157:H7. The sessile cells were reduced to a range of 13.8–31.3% by young radish, radish, radish sprout, red cabbage, and kale extracts, and the viability was reduced to between 5.83 and 51.5%. The radical scavenging activities and the presence of polyphenolic compounds were compared. The presence of phenolic compounds such as gallic acid, caffeic acid, and phenylethyl ITC in the Brassicaceae family verified the potential use as a natural anti-biofilm substituent against E. coli O157:H7.