Detection Escherichia Coli O157 contamination in soymilk from traditional market at Denpasar City

Abstract

Escherichia coli are normal flora in human. Food and beverage contained Escherichia coli is a feces contamination indicator. One of pathogen Escherichia coli strain is serotype O157. Escherichia coli O157 causes bloody diarrhea and Hemolytic Uremic Syndrome. Reservoir can be derived from animal, human and water. In this study we used 80 sample of soy milk sold in traditional market at Denpasar City. The aim of this study is to identify Escherichia coli O157 and isolate Escherichia coli O157 containing gen shiga like toxin-2. Mac Conkey was used to differentiate between Escherichia coli and coliform that appeared in pink colour colonies. The colonies were obtained for Gram staining which was then examined by biochemical test (imvic). Positive Escherichia coli identified by imvic test, bred on SMAC and observed colonies. Colourless colonies identified as presumptive Escherichia coli O157 and to support identification was done single path test and latex agglutination test. The result showed that were 32 out of 80 soymilk sample contained Escherichia coli. Presumptive Escherichia coli O157 were found of 4 out of 32 isolate Escherichia coli (12,5%). All presumptive sample of Escherichia coli O157 were examined by the PCR procedures which were not contained of gen shiga like toxin-2. Contamination Escherichia coli O157 in soymilk showed poor hygienic processed soymilk include use to water contamination.