Occurrence of pathogenic Escherichia coli in commercially available fresh vegetable products in Korea

Abstract

Pathogenic E. coli is a major foodborne pathogen associated with gastroenteritis worldwide. Fresh vegetable products as well as raw meat and meat products have been recognized as important modes of transmission within the foodborne route. The objective of the present study was to determine the presence of six virulence factors (stx 1, stx 2, lt, st, eaeA, and ial) in E. coli isolated from fresh vegetable products to provide information on risk assessment of pathogenic E. coli in Korea. From 416 collected samples, including vegetable salad mix, sprouts, baby leaf vegetables, and unpasteurized fruit and vegetable juices commercially available in Korea, a total of 30 samples were positive for E. coli strains, resulting in an overall prevalence of 7.2%. Of the 120 E. coli isolates, only one isolate (0.8%), which was obtained from unpasteurized fruit and vegetable juices, was confirmed to possess the eaeA gene, but lacked stx genes. This study showed that some fresh vegetable product samples were contaminated with enteropathogenic E. coli.