Koliformnyh bacteria in water have long been used as indicators of possible contamination of water by intestinal parasites and pathogens. While most bacterial intestinal groups are not pathogenic, they are valuable indicators because they are more likely than pathogenic bacteria, have more vitality in fresh water, and relatively easy to identify. Since it's impossible to test each agent in the evaluation of water quality, the researchers tested for real easy to identify indicator organisms on the assumption that the murder of indicator organisms and pathogens are excluded during the process of disinfection. Coli-form includes a wide range of bacteria, the main source can not be the gastrointestinal tract. Fecal Escherichia is a subset of typical gastro-intestinal tract of warm-blooded animals and can be separated from other bacteria Escherichia coli, because they grow more stringent temperature of 44. 5 ° CE intestinal
is a special type of fecal bacteria koliformnyh and is one of the most frequently used indicators for human and animal fecal waste. Many strains of E. coli exist, while most are harmless, some strains such as E. coli O157: H7 can cause serious illness and possible death. Various tests exist for detection of intestinal in water. The most basic of these is
presence-absence (P / A) test, which assesses the presence or absence of
total intestinal and / or E.coli. If the total intestinal detected in 100 ml of water is not considered suitable for drinking. Nevertheless, the qualitative test, such as P / Test for total coli or E. coli in water does not mean its suitability for other purposes, such as swimming or bathing. Quantitative tests can determine the suitability of water for bathing and swimming. These include >> << Membrane filtration (MF) technique and most probable number (MPN) technique. Intestinal density is buy strattera reported, the number of colony units (CFU) per 100 ml of water. MF method is fast and simple method of estimation of bacterial population in water. Samples of water passing through 0. 45 micron filter. Filter and trap bacteria transmitted to the surface environment that will support the growth of bacteria that can be identified based on morphological features of their colonies. Since this method accommodates testing of large numbers of samples simultaneously, it is especially useful for drinking water. Method of PV, however, is limited to samples that do not contain high levels of background organisms, suspended solids, sediment, or metals. The method involves incubation of MPN samples of various dilutions of intestinal specific media to determine the number of bacteria in the sample statistically. It is ideal for wastewater and sludge applications because analysts can use very turbid samples by diluting the sample before analysis. Image Reference:
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