The Development and Evaluation of a Selective Enrichment for the Detection of <i>Escherichia albertii</i> in Food

Abstract

<i>Escherichia albertii</i> is an emerging pathogen causing foodborne infections with diarrhea, abdominal pain, and fever. <i>E. albertii</i> has been isolated from various food sources, such as chicken and pork. Although many foodborne outbreaks of <i>E. albertii</i> have been reported, the causative food has not been identified. It is necessary to develop effective detection methods for <i>E. albertii.</i> Because enrichment procedure as the first step of food test is important for growing pathogens, this study aimed to develop a novel effective enrichment for <i>E. albertii</i> detection in food. In this study, we investigated the optimal concentration and combination of cefixime and tellurite for supplementing modified EC broth (mEC) to effectively isolate <i>E. albertii</i> from chicken meat. The results showed that mEC supplemented with 50 μg/L cefixime and 2.5 mg/L tellurite (CT-mEC) inhibited the growth of competitive bacteria in chicken meat but not that of <i>E. albertii</i>. Therefore, it was indicated that CT-mEC had strong potential to selectively grow <i>E. albertii.</i> In an <i>E. albertii</i> foodborne outbreak, CT-mEC was evaluated. <i>E. albertii</i> was successfully isolated from a food sample, a kind of salad, by enrichment with CT-mEC but not buffered peptone water and mEC. In this study, CT-mEC as a selective enrichment broth has been developed to detect <i>E. albertii</i> in chicken meat. It was demonstrated that the selective enrichment broth was effective for the efficient detection of <i>E. albertii</i> in food.