Modification of sorbitol MacConkey medium containing cefixime and tellurite for isolation of Escherichia coli O157:H7 from radish sprouts.
A modified version of sorbitol MacConkey medium containing cefixime and tellurite (CT-SMAC medium) was produced by adding salicin and 4-methylumbelliferyl-beta-D-galactopyranoside to CT-SMAC medium; this medium was designated CT-SSMAC medium and was used to isolate Escherichia coli O157:H7 from radish sprouts. Of 101 non-E. coli bacteria isolated from radish sprouts that produced colorless colonies similar to colonies of E. coli O157:H7 grown on CT-SMAC medium, 92 (91%) formed colonies that were red to pink or were beta-galactosidase negative and colorless on CT-SSMAC medium. On the other hand, colonies of E. coli O157:H7 strains were colorless and beta-galactosidase positive on CT-SSMAC medium. Our results suggest that CT-SSMAC medium is more selective than CT-SMAC medium for isolating E. coli O157:H7.
Fujisawa
T
T
Kanagawa Prefectural Public Health Laboratory, Yokohama 241-0815, Japan.
Sata
S
S
Aikawa
K
K
Takahashi
T
T
Yamai
S
S
Shimada
T
T
D000818:Animals; D019607:Brassicaceae / Q000382:microbiology*; D002417:Cattle; D020682:Cefixime; D003470:Culture Media; D019453:Escherichia coli O157 / Q000254:growth & development* / Q000302:isolation & purification*; D005243:Feces / Q000382:microbiology; D006801:Humans; D013691:Tellurium
D003470:Culture Media; D020682:Cefixime; C026660:tellurous acid; D013691:Tellurium