2003 Volume 20 Issue 3 Pages 111-116
Test samples of water presented for the potability test were examined in XGM medium, and using the 112 samples that indicated positive for the coliform bacteria group, the results were compared with those obtained with LB medium. Furthermore, the strains of the coliform bacteria group isolated from XGM medium were subjected to identification tests to determine the bacterial type, and the characteristics of the strains isolated were also examined in the LB medium. With respect to the status of detection of organisms of the coliform bacteria group from potable water in each fiscal year, significant differences were noted depending on the test method employed. When the test results for the 112 samples that indicated positive for the coliform bacteria group in XGM medium were compared with those obtained in LB medium, the agreement rate was only 65.2%. When strains of the coliform bacteria group isolated in the XGM medium were subjected to identification tests to determine the bacterial type, the following results were obtained: Enterobacter represented 29.6%, Citrobacter 25.9%, Escherichia 13.2%, Aeromonas 11.6%, Klebsiella 7.9%, and Serratia 5.3%. Out of the 189 isolated strains of the coliform bacteria group isolated from the XGM medium, 114 strains showed positive result in LB medium, and the agreement rate was 60.3%.
