Prevalence of pathogenic Escherichia coli from salad vegetable and fruits sold in Jakarta

OBJECTIVE: Escherichia coli is a normal inhabitant of mammalian’s gut, but some strains acquired virulence factor and became pathogenic. Enterotoxigenic E. coli (ETEC), enterohemorrhagic E. coli (EHEC), enteropathogenic E. coli (EPEC), enteroinvasive E. coli (EIEC), and enteroaggregative E. coli (EAEC) are among pathogenic strains of E. coli. Vegetables and fruits could be sources of transmission. Samples were collected and subjected to three-tubes Most Probable Number (MPN) analysis followed by Multiplex PCR. Six sets of primer encoding virulence genes were used: stx, ipah, aggr, eae, elt and est. RESULTS: From this study we found, the highest maximum number for the MPN result reached > 1100 MPN/mL and the lowest is 3 MPN/mL. From first multiplex PCR showed 65 salad vegetable samples, 7.69% were positive and from the 63 fruit samples, 11.11% were positive. From second multiplex PCR for 76 isolates, 55 (72.37%) isolates were aggR positive (EAEC), 12 (15.79%) isolates were eae positive (EPEC), and 9 (11.84%) were elt positive (ETEC). Antimicrobial resistance assay showed that 83.33% of the isolates were multi resistant. Resistances are observed to 10 μg Ampicillin (22.22%), 5 μg Ciprofloxacin (11.11%), 10 μg Gentamycin (33.33%), 30 μg Kanamycin (38.89%), 10 μg Streptomycin (55.56%), 5 μg Trimethoprim (16.67%), and 300 U Polymyxin B (61.11%).