TITLE:
Non-Fermentative Gram-Negative Bacteria in Drinking Water
AUTHORS:
Daiva Staradumskyte, Algimantas Paulauskas
KEYWORDS:
Drinking Water; Microbiology; CDC; Pseudomonas
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.6 No.2,
February
25,
2014
ABSTRACT: The description of a microbiological community of
drinking water distribution systems is intended for a safe and proper use of
drinking water. These studies were aimed at characterising the microbial
condition of the drinking water supply system in Lithuania by means of
culture-based methods and biochemical techniques. Samples of drinking water (in
cities supplied in centralised way from taps, wells, and boreholes) were
collected in different locations in Lithuania. Seeking to grow microflora
present in water the membrane filtration method was applied to study the
samples. Most often water samples were studied to identify coliform bacteria (Citrobacter spp., Enterobacter spp., Klebsiella spp., Serratia spp.), Escherichia
coli (or faecal coliform), Enterococci (or fecal Streptococcus), Pseudomonas aeruginosa (other
non-fermentative gram-negative bacteria) according to the international ISO
standards. Large amounts of non-fermenting gram-negative bacteria were found in
centralised urban water. The investigation showed that more than 50% of the wells under study had
increased microbial contamination with faecal coliform bacteria and faecal Streptococcus.
Bacteria of the Pseudomonas group, CDC group and other non-fermentative
gram-negative bacteria were detected in more than 30% samples of centralised
urban water studied.