Toxicological examination of microbial isolate from sites located in freshwater ecosystem at Ugwuomu-nike, Enugu State

Abstract

The isolation and identification of bacteria associated with influx from human residues located in freshwater ecosystem at Ugwuomu-nike in Enugu State was examined in this study. About eight (8) water samples were collected, four (4) from the lake and the other four (4) from the river close to the residual points. The samples were physiochemically examined for Temperature, pH, Turbidity and Conductivity. Samples were centrifuged and viewed under the microscope for any presence of parasites to be identified. Water culture was carried out using lactose broth to check for possible acid and gas production by the test organisms, and further cultured into eosin methylene blue agar and macConkey agar incubated at 37 oC for 24-48 hours. The isolates were finally cultured on nutrient agar and stored in a stock culture bottles for further analyses. Biochemical testing was also carried out. The microorganisms isolated and identified were Proteus spp, Esherichia coli, Bacillus spp, Staphylococcus aureus, Legionella spp, Enterobacterspp and Micrococcus spp. The Bacillus spp (rod shaped), Staphylococcus aureus (cocci in clusters) and Micrococcus spp (cocci in pairs) turned to be gram positive and non-motile, having Bacillus spp a spore former and the other two species a non-spore formers. Proteus spp, Esherichia coli, Enterobacter spp and Legionella spp as gram negative, non-spore formers and motile microorganisms. Results showed that E.coli isolated was the most frequent organisms and when compared to the remaining microbial isolates after the biochemical analysis, E-coli isolates produced its result as indole positive, oxidase negative, catalase positive, citrate negative, urease negative, coagulase negative. However, when tested on glucose, lactose, and galactose, it produced acid and gas. This study confirms the presences of bacteria at the freshwater ecosystem because of human residues, hence the need for water treatment should be employed to avoid water borne diseases by contact and possible consumption by citizens in that surroundings.