Abstract
The membrane filter technique with AC agar medium supplemented with 0.04% NaN3 and 0.00015% 2, 3, 5-triphenyltetrazolium chloride for enumeration of enterococci in water is described. An appropriate volume of a water sample was filtered through the membrane filter. The membrane filter was put on an AC agar plate (designated as the AC⋅MF technique), which was incubated at 37C for 18hr and further at 45C for 24hr. By this AC⋅MF technique, all the colonies grown on the membrane filters were identified as enterococci, and the count of enterococci obtained by the AC⋅MF technique was similar to that by the AC⋅MPN technique. The AC⋅MF technique may be useful for accurate and rapid enumeration of enterococci in water and serve as a simple method for determining the sanitary quality of water.
