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Thermotolerant Coliform and Escherichia coli Detection and Enumeration Through Multiple Tube FermentationKeywords: Thermotolerant coliforms , E. coli , Tryptophane , Tryptophanase , modified media Abstract: The first objective of present study was to comparing the Modified (M) and Standard (S) media using MPN-technique for simple and rapid detection of Faecal Coliform (FC) and E. coli in different aquatic environments. The second objective was the comparison between the efficiency of four modified media (M-m7hfc broth, M-A-1, M-MacConky and M-EC media) for detection and enumeration of faecal coliform and E. coli especially in water sources. The results of MPN ratios between modified and standard media (M/S media) for each of FC and E. coli were more greater than one time, indicating more suitability for the modified formulas. Results indicate that a high faecal coliform recovery was recorded using M-EC medium from water samples. All sewage and ground water samples showed good results when using M-m7hfc broth and M-A-1 media, respectively. A high recovery of E. coli detection was observed using M-MacConky and M-A-1 media from sewage, treated sewage Nile and ground water samples. M-EC and M-MacConky media gave a high E. coli recovery from sludge samples. This comparison illustrates the MPN-technique with M-EC and M-MacConky a s the best performance characteristic of all media tested as judgment for FC or E. coli recovery with great efficiency and specificity in the tested water sources. Thus MPN-technique with modified media approach as described here proved suitable for the rapid, sensitive, specific and economic means for the detection and enumeration of FC and E. coli from different aquatic environments in a single step at the same time.
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