Blood agar and sodium pyruvate were used to improve the recoverability
and trimethoprim was used as an additional supplement in
this study to exclude high background microflora in foods. It appears
that trimethoprim effectively excluded some competing microflora,
which was resistant to high concentrations of polymyxin B in Korean
traditional spices or RTE vegetables, rendering the differentiation of
suspicious colonies easier.
In the present study, a selective medium for B. cereus was developed
and evaluated using pure culture and food samples. Our results demonstrate
that this newly developed selective medium may be a useful
alternative to MYPA for its selectivity particularly for foods with high
background flora.