IDENTIFIKASI BAKTERI Coliform PADA BEBERAPA DEPOT AIR MINUM ISI ULANG DI DELI SERDANG

The method used in this method is descriptive research with a laboratory approach. Samples of 15 drinking water depots were taken from 15 different sub-districts in Deli Serdang Regency. The test was carried out using the Most Probable Number (MPN) method through three stages: presumptive test using Lactose Broth media, confirmation test with BGLB (Brilliant Green Lactose Bile Broth) media, and complete test with EMB (Eosin Methylene Blue Agar) media. Identification of suspected Escherichia coli was done based on colony characteristics on EMB media. Results: The results showed that 5 out of 15 samples (33.33%) were positive for Coliform bacteria, and 2 of them showed metallic green shiny colonies that were suspected to be Escherichia coli. The highest MPN value was 240/100 mL, found in samples from Tanjung morawa and Galang sub-districts.