In the case of neutralization of disinfectants such as quaternary ammonium is quite important to the antimicrobial activity, it is recommended to use Letheen Broth of Swab Sampler to test preservative materials.

Microbiology Agar Medium Types
AC ? Standard Plate Counting Agar Based Medium
Used for the identification of the total bacteria number.

EC ? Three-color Agar Based Medium
Escherichia coli and coliforms can be simultaneously detected.
E.coli colonies are blue to light purple.
Coliform colonies are red to purple.
Other intestinal bacterial colonies were milky white.