Study of biofilm in bacteria from water pipelines

Abstract

Context: A biofilm is a layer of microorganisms contained in a matrix (slime layer), which forms on surfaces in contact with water. Their presence in drinking water pipe networks can be responsible for a wide range of water quality and operational problems. Aim: To identify the bacterial isolates, obtained from water pipelines of kitchens, to evaluate the water quality & to study the biofilm producing capacity of the bacterial isolates from various sources. Settings and Design: A prospective study using water samples from aqua guard & pipelines to kitchens of S.C.B Medical College hostels. Materials and Methods: Standard biochemical procedures for bacterial identification, multiple tube culture & MPN count to evaluate water quality & tissue culture plate (TCP) method for biofilm detection was followed. Statistical analysis: STATA software version 9.2 from STATA Corporation, College station road, 90 Houston, Texas was used for statistical analysis. Results: One hundred eighty seven isolates were obtained from 45 water samples cultured. The isolates were Acinetobacter spp. (44), Pseudomonas spp.(41), Klebsiella spp.(36) & others. Biofilm was detected in (37) 19.78% of the isolates (95% CI 30.08% -43.92%) including Acinetobacter spp.-10, Klebsiella spp. - 9, Pseudomonas spp. - 9, & others, majority (34) of which were from kitchen pipelines. Conclusion: Water from pipeline sources was unsatisfactory for consumption as the MPN counts were > 10. Most of the biofilm producers were gram negative bacilli & Pseudomonas & Acinetobacter spp. were strong (4+) biofilm producers.