Study on killing mechanism of one atmosphere uniform glove discharge plasma (OAUGDP)

[Objective] To explore the germicidal mechanism of OAUGDP so as to provide useful fundamental data in this area and make better use of plasma in disinfection. [Methods] Several index microorganisms of interest to the healthcare industry including Escherichia coli, Staphylococcus aureus and Candida albicans were used as subjects for comparison. The leakage of protein, malonic dialdehyde(MDA) produced by oxidation of lipid in bacteria and Superoxide Dismutase(SOD) that reflex the anti-oxidation ability of bacteria have been tested after being exposed to plasma. The break of DNA double-strand of Escherichia coli was also observed in this study. [Results] When exposed to the plasma, the bacteria's leakage of protein, amount of MDA significantly increased and the amount accumulated with the prolongation of exposure time, at the same time the activity of SOD was compromised after exposure and there seemed a dose-response trend between the reduction ability of SOD and increase in exposure time. After being exposed to the plasma for 60 seconds, there was a significant break of DNA double-strand.