Comparative assessment of the relation between energy consumption and bacterial burden reduction using plasma activated water

The aim of this paper is to present a comparative assessment between energy consumption of the non-thermal plasma generator and burden reduction in Gram-negative and Gram-positive bacteria using plasma-activated water. There is well known that plasma discharges are able to remove all unwanted organic contaminants, but recently, it was discovered that is possible to produce water with specific physical, chemical properties with an important biological impact that develops new methods of decontamination. However, this bio-effect has not been examined from an economical point of view. For this comparative study, the plasma-activated water was produced using a gliding arc plasma configuration reactor. The plasma generator is supplied by an AC high voltage transformer, which has an output voltage of 10 kV and a maximum output current of 100 mA. The gliding arc discharge operates at an industrial frequency of 50 Hz and uses air as gas carrier. A volume of 300 mL of sterile distilled water was exposed to the plasma for 10 min in the reactor made of glass, l, and then used as a disinfectant after 5 min. The new disinfecting product (Plasma activated water) was subjected to several “in vitro” tests that include antimicrobial assays on representative strains belonging to Gram-negative (Proteus mirabilis, Klebsiella pneumonia, Salmonella derby, Proteus vulgaris) and Gram-positive (Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Bacillus anthracis, Staphylococcus intermedius, Methicillin-resistant Staphylococcus aureus) bacteria.