Microbial inactivation using plasma-activated water obtained by gliding electric discharges

Aim: To evaluate the microbial disinfection efficacy of a plasmachemical solution obtained by the activation of water with gliding electric discharges. Methods and Results: Distilled water was activated for 5 min by a nonthermal quenched plasma of the glidarc type operating in humid air and at atmospheric pressure. The plasma-activated water (PAW) was then used to treat planktonic and adherent cells of Staphylococcus epidermidis, Leuconostoc mesenteroides (as models of Gram-positive bacteria), Hafnia alvei (a Gram-negative bacteria) and Saccharomyces cerevisiae (as a yeast model). The treatments were less efficient on adherent cells than on planktonic cells in the case of bacteria, but not of S. cerevisiae. Inactivation was more effective for bacteria than for the yeast. Conclusions: Significant reductions in microbial populations were achieved in all cases, demonstrating the effectiveness of this new approach to treat contaminated media. Significance and Impact of the Study: PAW is a promising solution with potential application to the decontamination of equipment and surfaces.