Give the standard scientific definition of “coliform”. Are coliforms indicator organisms (YES OR NO)? Explain why the total bacterial acceptable levels are higher than the coliform acceptable levels.
Bacteria are defined as single-celled micro-organism which has a simpler structure than other organisms as they lack membrane-bound organelles as well as nucleus. These are found in every habitat on our planet such as soil, rivers, oceans, rocks, and even arctic snow. These are considered as 'friends' as well as 'foe' as they are proved beneficial for us (as those residing in our digestive system or gut where it causes breakdown of foods and makes us remain healthy) as well as harmful also as it may cause infections.
Coliforms are defined as bacteria which are gram-negative, rod-shaped, non-sporulating and either motile or immotile which can ferment lactose with the generation of gas and acids when incubated at 35-37 degree centigrade and do or do not require oxygen for its growth i.e., facultative anaerobes.
Yes, coliforms are known as indicator organisms because their existence in foods specifies that conditions are favorable for the appearance of enteric pathogens which marks inadequate sanitary conditions.
According to Environmental Protection Agency (EPA), maximum level of contaminants for coliform bacteria is zero or none in drinking water per 100 ml of water. Thus, the total bacterial acceptable levels are higher than the coliform acceptable levels as it has level equal to zero.