To study the effects of exposure to extremely low frequency electromagnetic fields both on biofilm formation and on mature biofilms of bacterium Helicobacter pylori (i.e. bacterical cultures and two day old biofilms).
Exposure duration: continuous for 2 days
|Setup||450 mm long cylindrical solenoid with an inner diameterr of 170 mm and 180 turns of copper wire, placed vertically in an incubator; field homogeneity 1 % in the center of the solenoid; cells placed on a non-magnetic support in the center of the solenoid|
|Sham exposure||A sham exposure was conducted.|
|magnetic flux density||1 mT||-||-||-||-|
The extremely low frequency electromagnetic fields affected the bacterial population during the biofilm formation displaying significant differences in cell viability (decrease under exposure) as well as in morphological types measured by the prevalence of spiral forms. In contrast, in mature biofilms no significant differences were found when compared to the controls. The biofilm cell mass was significantly reduced in exposed cultures in both experimental conditions (i.e. mature biofilms and cell cultures), i.e. the extremely low frequency electromagnetic field exposure inhibited the biofilm formation and reduced cell adhesion. No changes in DNA patterns (genotype) were recorded, whereas a modulation in amiA gene expression (higher levels under sham exposure) was detected.
In conclusion, an exposure of Helicobacter pylori biofilm to extremely low frequency electromagnetic fields induced phenotypic changes (bacterial morphology) and decreased the cell adhesion. Thus, the Helicobacter pylori balance is disturbed by the electromagnetic field exposure reducing the bacterium's capability to protect itself.