Sysolyatina E.,Gamaleya Institute of Epidemiology and Microbiology |
Mukhachev A.,Gamaleya Institute of Epidemiology and Microbiology |
Yurova M.,Gamaleya Institute of Epidemiology and Microbiology |
Grushin M.,SRC RF TRINITITroitsk |
And 5 more authors.
Plasma Processes and Polymers | Year: 2014
Inactivation of microorganisms by plasma of a positive (PC) and negative corona (NC) discharge in air at atmospheric pressure was investigated. Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Pseudomonas aeruginosa were chosen for the discharge inactivation. PC and NC produce three types of bactericidal agents, which are ultraviolet radiation (UV), neutral reactive species (R), and electric field and charged particles (E), respectively. We elucidated the contribution of each bioactive agent to the inactivation of S. aureus and P. aeruginosa. The influence of the charged particles in PC and NC on the cell inactivation is caused by different electrophysical effects, which lead nevertheless to an identical consequence: the cell membrane becomes more transparent for neutral reactive species. It gives additional possibility for neutral reactive species to increase the inactivation of cell by biochemical mechanisms. Due to that, total UV + R + E bactericidal effect in PC and NC is approximately the same and great - only a few tens of seconds is enough to inactivate completely S. aureus and P. aeruginosa cells. Bacteria inactivation in corona by positive and negative ions is rather biophysical than biochemical process. Fast accumulation of huge positive charge on cell results in electrical breakdown of the membrane accompanied with a formation of numerous large pores; low current of negative ions OH- results in fatal increase of the cell membrane permeability. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.