Gram-negative identification card for identification of Salmonella, Escherichia coli, and other Enterobacteriaceae isolated from foods: collaborative study.
Twelve laboratories evaluated the Gram-Negative Identification (GNI) Card to identify members of the Enterobacteriaceae. Eighty-four isolates, previously isolated from foods, were used in the collaborative study; the isolates represented 12 genera within the Enterobacteriaceae group. Each collaborator streaked each isolate on tryptic soy agar plates for purity. In the method, plates are incubated 18-24 h at 35 degrees C. Isolated colonies are then subcultured to tryptic soy agar slants and incubated 18-24 h at 35 degrees C. An emulsion is made from the growth on the slant in 1.8 mL 0.45% sodium chloride solution. The GNI Card is filled and placed in a reader/incubator. Isolates are identified and an identification is printed. The Vitek System correctly identified 96.7% of Salmonella sp., 97.0% of Escherichia coli, and an average of 93.8% of the other enteric genera. The method using the Vitek System and GNI Card has been approved interim official first action by AOAC as a screening method for the presumptive identification of Salmonella sp., E. coli, and other Enterobacteriaceae isolated from foods.
Knight
M T
MT
Q Laboratories, Inc., Cincinnati, OH 45214.
Wood
D W
DW
Black
J F
JF
Gosney
G
G
Rigney
R O
RO
Agin
J R
JR
Gravens
C K
CK
Farnham
S M
SM
D003470:Culture Media; D004755:Enterobacteriaceae / Q000302:isolation & purification*; D004926:Escherichia coli / Q000302:isolation & purification*; D005516:Food Microbiology; D007202:Indicators and Reagents; D011933:Reagent Kits, Diagnostic; D012475:Salmonella / Q000302:isolation & purification*
D003470:Culture Media; D007202:Indicators and Reagents; D011933:Reagent Kits, Diagnostic