Development of Listeria monocytogenes detection technique in mushroom based on real-time quantitative PCR through improvement of enrichment medium

Abstract

The objective of this study was to develop precise and rapid detection methods for Listeria monocytogenes in mushrooms when using real-time PCR. L. monocytogenes were enriched through the optimization of the enrichment broth. To determine the optimal supplement for bacterial growth, the various components were investigated. As a result, LEB with 2×ferric citrate (LEB+2FC) was shown the most effective on promoting the L. monocytogenes growth in mushrooms. L. monocytogenes was inoculated in King Oyster mushroom and Golden needle mushroom, and the samples were enriched. Consequently, L. monocytogenes in King Oyster mushroom was detected by 100% (8/8) using real-time PCR when enriched in LEB+2FC for 9 h. In Golden needle mushroom, the pathogen was detected (100%; 8/8) when enriched in LEB+2FC for 3 h. These results indicate that L. monocytogenes can be detected quickly to prevent Listeria-related foodborne illness from the consumption of mushrooms with enrichment using LEB+2FC and real-time PCR analysis.