Analysis of Various Water Samples for Enterobacteriaceae by MPN Method

Abstract

This study was designed in such a way to identify the coliforms that were present in water that were taken from study villages. The villages that were identified for this study were Edayarpalayam, Ettimadai and Malumichampatti. Naturally, coliforms in turn cause diseases like typhoid and cholera etc. Three drinking, three tap water samples and a Recreational water sample were analyzed by MPN method. The presumptive, confirmed, completed tests were carried out for analysis. The results of the study indicate the presence of coliforms especially fecal forms were identified. According to the MPN standard table three drinking water sample were shown more than 10 coliforms per 100 ml of water sample. Whereas three tap water samples (IV, V & VI) has more than 1100 per 100 ml of water. Sample VII is said as recreational water it also has more than 1100 coliforms. MPN count was taken from standard MPN Index table. IMVIC tests were performed in order for the further characterization for fecal Coliforms. Hence the results of this study suggest that invariably all samples had higher MPN index value more than 10.  On the other hand three of the tap water was at high risk as it contains highest number of coliforms more than 100. After the completed test (EMB) the organisms streaked on SS Agar, it showed positive results based on color of colonies indicates the presence of Salmonella and Shigella spp. Finally the suspected colonies were streaked on MaConkey agar for determination of E.coli and Shigella spp. This study suggests sanitation and chlorination etc may help the usage of contaminated drinking water. The tap water source also to be sanitized and it may not be used as alternative for drinking water at any instances.