Biomimetic surfaces inspired by cabbage leaves for Escherichia coli biofilm prevention in the food industry

Food contact surfaces are usually colonized by microorganisms, even following cleaning and disinfection. They can grow as biofilms, which are contamination sources of finished products, reducing their shelf life and causing foodborne diseases. One way to reduce fouling is to design naturally cleaning surfaces based on biomimetic designs. Four self-cleaning leaves (Tenderheart cabbage, Cauliflower, White cabbage, and Leek) were analysed for their surface properties along with their biomimetic replicates. The leaves and artificial replicates were subjected to retention assays using Escherichia coli as a model organism. All the surfaces were non-wettable (water contact angles higher than 100 °), with the biomimetic Tenderheart cabbage demonstrating the most non-wettable surface. However, when the hydrophobicity of the surfaces was determined, the White cabbage was demonstrated to be the most hydrophobic surface (  ≈ - 88 mJ m^-2). The natural White cabbage also presented the lowest roughness values (  = 3.5 µm), although the corresponding replica was the roughest of the fabricated surfaces (  = 5.3 µm). The Leek leaves retained more E. coli cells than the other cabbages and it was found that surface hydrophobicity was not a controlling factor in the bacterial retention. The biomimetic surfaces were more efficient at avoiding bacterial retention than natural leaves, indicating that the nano-scale topography associated with the natural leaves is not essential for its antifouling performance in the tested environment. A reduction in bacterial retention of about 1 log was obtained with most of the surfaces produced, validating the idea that biomimetic surfaces inspired by self-cleaning leaves may have some potential for the development of industrial antifouling surfaces.