E.coli and Coliforms

Culture Medium: E.coli and Coliform Selective Media (ECC)

Culture Medium : Modified E.coli and Coliform Selective Media(ECCPlus)

Escherichia coli and total coliform numbers are often used as a hygiene indicator, due to their association with faecal contamination.

A standard culture medium for the growth of coliforms, E.coli and Coliform Selective Media is a selective medium containing several components which suppress Gram-positive organisms and non-bile tolerant Gram-negative organisms. It is also a differential medium, containing a pH indicator system whereby growth of coliform species, which are able to ferment lactose, leading to a colour change of the medium from purple to yellow.

Use of the E.coli and Coliform Selective Media with incubation temperatures of 36°C will facilitate the detection of total coliforms. Increasing incubation temperature to 44°C increases the selectivity of the medium such that only E. coli will be detected, the non-E. coli species of coliforms unable to tolerate the higher temperature.