Effect of dilution factor on the isolation of Helicobacter pylori from municipal wastewater using culture technique

Mehri Solaimany Aminabad; Mahdi Hadi; Seyedeh Zohreh Mirbagheri; Alireza Mesdaghinia; Ronak Bakhtiari; Masoud Alebouyeh; Shahrokh Nazmara

doi:10.18502/ijm.v14i6.11264

Mehri Solaimany Aminabad Center for Water Quality Research (CWQR), Institute for Environmental Research (IER), Tehran University of Medical Sciences (TUMS), Tehran, Iran
Mahdi Hadi Center for Water Quality Research (CWQR), Institute for Environmental Research (IER), Tehran University of Medical Sciences (TUMS), Tehran, Iran
Seyedeh Zohreh Mirbagheri Pediatric Infections Research Center, Research Institute for Children‘s Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Alireza Mesdaghinia Center for Water Quality Research (CWQR), Institute for Environmental Research (IER), Tehran University of Medical Sciences (TUMS), Tehran, Iran
Ronak Bakhtiari Division of Microbiology, Pathobiology Department, School of Public Health and Institute of Public Health Research, Tehran University of Medical Sciences, Tehran, Iran
Masoud Alebouyeh Pediatric Infections Research Center, Research Institute for Children‘s Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Shahrokh Nazmara Center for Water Quality Research (CWQR), Institute for Environmental Research (IER), Tehran University of Medical Sciences (TUMS), Tehran, Iran

DOI: https://doi.org/10.18502/ijm.v14i6.11264

Keywords: Helicobacter pylori; Wastewater; Culture techniques

Abstract

Background and Objectives: Isolating Helicobacter pylori (H. pylori) from wastewater and culturing it using a convention- al method has always been acontroversial issue because the bacterium converts into a coccoid form when exposed to an un- favourable environment like wastewater. To clarify thecultivability behaviour of the bacterium in fresh wastewater samples, the effect of municipal wastewater dilation on the cultivation of the bacterium using a conventional method was examined.

Materials and Methods: Several dilutions of wastewater samples were inoculated with fresh H. pylori suspension(with McFarland's dilution 0.5) to examine the dilution effect of wastewater on the bacterium isolation.

Results: The H. pylori growth was found to be possible for a dilution factor from 1/106 to 1/107 of raw wastewater. In higher dilution factors the growth of fungi was dominant and could prevent the isolation of the bacterium.

Conclusion: The optimized technique could be applied in future studies for increasing the chance of H. pylori isolation from fresh wastewater environments.