The effect of physico-chemical treatment in reducing <i>Listeria monocytogenes</i> biofilms on lettuce leaf surfaces

The purpose of this research was to characterize Listeria monocytogenes from several environmental and clinical sources assess the efficacy single combined physico-chemical treatments in reducing biofilm on lettuce leaves. PCR analysis L. isolates collected different (10 strains) (12 used look for presence one Listeria-specific gene five virulence genes. Biofilms were developed leaves over 24 h. A 5-min ultrasound a 300-ppm sodium hypochlorite (NaOCl) wash resulted similar reductions cell numbers 0.82 log CFU cm?2. For chlorine dioxide (ClO2) at 60 ppm, reduced by ?5.45 treatment 5 min plus 300 ppm NaOCl or 40 ClO2, provided maximal efficacy, number surface non-detectable levels. Therefore, ClO2 has potential replace disinfection food products industry.