Quorum Sensing and Spoilage Potential of Psychrotrophic Enterobacteriaceae Isolated from Milk

Figure 4

Representative thin-layer chromatograms of the signal molecules present in cell-free supernatants of Enterobacteriaceae strains isolated from cooled raw milk and cultivated in LB medium. The spots were detected with E. coli pSB403 reporter strain. Standards: N-(hexanoyl)-DL-homoserine lactone (HHL); N-(octanoyl)-L-homoserine lactone (OHL); N-(dodecanoyl)-L-homoserine lactone (DHL); N-(3-oxohexanoyl)-L-homoserine lactone (OHHL). (059) H. alvei, (067) Enterobacter sp., (068) H. alvei, (039) Pantoea sp., (071) H. alvei, and (099) A. hydrophila.

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