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Table 6 Presumptive Cronobacter spp. as appeared through testing the isolates by biochemical profiling (API20E), chromogenic (α-MUG, DFI, EsPM) and eight sets of Cronobacter spp- specific primers (α-gluA, α-gluB, SG, SI, Saka, OmpA, zpx and BAM), while confirmed as non-Cronobacter spp. by 16S rRNA sequence analysis.

From: Isolation of Cronobacter spp. (formerly Enterobacter sakazakii) from infant food, herbs and environmental samples and the subsequent identification and confirmation of the isolates using biochemical, chromogenic assays, PCR and 16S rRNA sequencing

Isolate      PCR Primers  
ID Source API 20E α-MUG DFI EsP M α-GluA α-GluB SG SI Saka OmpA zpx BAM 16S rRNA
Jor20A Spices + - - Clear - ND + + - - + - N.Crono
Jor27 Chamomile + - - Y& - ND + + - - + - N.Crono
Jor45 Sugar + - - Gray - ND + + - - + - N.Crono
Jor115A Dates + + NG@ Y/Gr - ND - - - - + - N.Crono
Jor115B Dates + + NG@ Y/Gr - ND - - - - + -*# N.Crono
Jor51 Dry dairy + + + Y/Gr## - ND + + - - + - # N.Crono
Jor153B Semolina + + + BB - - + + - - + - N.Crono
Jor26 Rice + - - BB - - + + - - + + N.Crono
Jor100 Semolina + - - BB + ND + + - - + + N.Crono
Jor103 Spices + - - BB + ND + + - - + + N.Crono
Jor109 Grapes + - - BB + ND + + - - + + N.Crono
Jor168 Spices + - - BB - - + + - - + + N.Crono
Jor151 Fennel + + + BB - + - - - - + + N.Crono
Total +   13 5 3 7 3 1 10 10 0 0 13 6  
  1. The PCR conditions for BAM primers as described in Table 1 were used for amplification of both regions of the zpx gene as described by Kothary et al. [13]. * multiple bands. *#, PCR product was approximately (400 bp) and sequence was found not to be zpx. & Y, yellow colony chromogenic reaction color, 24 h at 37°C. Gr, green colony chromogenic reaction color, 24 h at 37°C. @ NG; no growth on DFI at 37°C. ##Colonies were blue black (BB) after three days at 37°C. N. Corono; None Cronobacter spp.