Summarize the primary methods of assessing the microbiological
quality of water.
Safe water is highly essential for good health of human beings. Water contaminated with fecal material is common in regions with poor hygienic condition and sanitation. Thus, determination of microbiological quality of water is highly essential.
Coliform bacteria are those present in environment as well as in feces of warm blooded animals and humans. These organisms will not cause illness but the presence of coliform bacteria in water is an indicator of fecal contamination of water and it indicates that there are possible chances for the presence of pathogenic organisms in water. E.coli is an example of coliform bacteria and it can be detected by various methods.
Membrane filter method is one of the simple and primarily used method. In this method, 1000 ml of water sample is poured through the filter and this filter is placed on MI agar and incubated at 35°C for 24 hours. In this method, the filter used will retain the coliform present in water and after incubation it will grow and develop blue colored colonies. The appearance of blue color is due to the break down Indoxyl- beta-D-glucuronide present in MI agar by E.coli and thus it indicates the presence of E.coli in water.
Step by step
Solved in 3 steps