Mix the contents of each bottle.
Incubate the inoculated broth in a water bath at 44 Oc for 24 hours with the botles loosely capped.
After incubation, examine and count each bottle which has produced acid and gas.
Determine the most probable number (MPN) of fecal coliform bacteria in the 100 ml of treated and 105 ml of untreated water sample with referring to probablity tables.
NB: Acid production is shown by a change in color of the Mac Conkey broth from purple to yellow and gas production by the collection of a bubble in the durham tube.
Interpretation of results
1. For treated water sample . The E.coli count should never exceed 5 per 100ml.
E. coli count
2. For untreated water sample
E. coli coun