Culture Media for the Isolation of Aeromonas spp. and Plesiomonas shigelloides

Abstract

The genera Aeromonas and Plesiomonas, previously included in the family Vibrionaceae, are now reclassified in the family Aeromonadaceae and Enterobacteriaceae, respectively. They are primarily aquatic inhabitants. Aeromonas taxonomy has changed considerably in recent years and now at least 19 phenospecies have been defined. Although identification to the species level of the most commonly found Aeromonas can be done on the basis of a limited number of biochemical tests, identification of some species is more difficult. Plesiomonas sligelloides is the only species of the genus Plesiomonas. Culture media components used for Aeromonas and Plesiomonas isolation is reviewed here. This chapter also reports on the media used for the isolation of Aeromonas and Plesiomonas from foods and comparative studies. In the case of Aeromonas spp., the most promising media are starch ampicillin agar (SAA) and bile salts Irgasan brilliant green (BSIBG) agar as plating media, and alkaline peptone water (APW) or trypticase soy broth ampicillin (TSBA) as enrichment broths. With regard to P. shigelloides, it is more difficult to make recommendations, but enrichment in APW or tetrathionate broth without iodine and plating on inositol brilliant green bile salts agar (IBB) and Plesiomonas agar (PL) can be useful.