Microbial growths on various types of treated water /
Microbial growths on various types of treated water /
Carmelita B. Cuyugan, Maria Imelda D. Vitug
Safe, uncontaminated drinking water is of utmost importance in public health maintenance. With this in mind, a descriptive study on 4 types of treated water samples, namely, distilled, reverse osmosis, autoclaved and boiled water were tested for microbial growths by inoculating in McConkey agar and Lactose broths in 8 hour intervals for a duration of 3 days. Samples were divided into 2 groups and subjected to room (group A) and refrigerated (group B) temperatures. After incubation for 48 hours, faecal coliforms were not detected in any of the samples but each type of treated water exhibited growths of different kinds of opportunistic pathogens, namely, Pseudomonas, Acinetobacter and Enterobacter. Reverse osmosis samples had the most number of microbial colony counts identified as Pseudomonas species of up to 7333 CFU/100ml in 72 hours which were not found in boiled water. Prolonged exposure to room air favored growths of these pathogens while keeping them at refrigerated temperature significantly decreased their growths.
Makati Medical Center Proceedings, 1999 (13) pages 84-88
Drinking Water--analysis
Drinking Water--microbiology
Water Purification--methods
Water Supply--standards
Safe, uncontaminated drinking water is of utmost importance in public health maintenance. With this in mind, a descriptive study on 4 types of treated water samples, namely, distilled, reverse osmosis, autoclaved and boiled water were tested for microbial growths by inoculating in McConkey agar and Lactose broths in 8 hour intervals for a duration of 3 days. Samples were divided into 2 groups and subjected to room (group A) and refrigerated (group B) temperatures. After incubation for 48 hours, faecal coliforms were not detected in any of the samples but each type of treated water exhibited growths of different kinds of opportunistic pathogens, namely, Pseudomonas, Acinetobacter and Enterobacter. Reverse osmosis samples had the most number of microbial colony counts identified as Pseudomonas species of up to 7333 CFU/100ml in 72 hours which were not found in boiled water. Prolonged exposure to room air favored growths of these pathogens while keeping them at refrigerated temperature significantly decreased their growths.
Makati Medical Center Proceedings, 1999 (13) pages 84-88
Drinking Water--analysis
Drinking Water--microbiology
Water Purification--methods
Water Supply--standards