Biondikator pencemaran, bakteri Escherichia coli

BIOINDICATOR OF CONTAMINANT, BACTERIA Escherichia coli. Indicator organisms are used to measure polantetial facel contamination of environmental samples. the presence of coliform bacteria, such as Escherichia coli, in surface water is a common indicator of fecal contamiminantion. coliform bacteria in water samples may be quantified using the most probable number (MPN) method, a probabilistic test which assumes cultivable bacteria are present at numbers in excess of an established cut-off (the coliform index), fecal contamination is suspected and confirmatory assays such are conducted. coliform bacteria selcted as indicator of fecal contamination must not persist in the environment for long periods of time following efflux from the intestine, and their presence must be closely correlated with contamination by other fecal organisms