Inactivation of Pseudomonas aeruginosa and Methicillin-resistant Staphylococcus aureus in an open water system with ozone generated by a compact, atmospheric DBD plasma reactor

Abstract

Ozone is a well-known disinfecting agent that is used as an alternative for chlorine in many applications, including water decontamination. However, the utility of ozone in water decontamination is limited by high electrical power consumption and expensive, bulky equipment associated with ozone generation. This study investigates the effectiveness of a lightweight, compact surface dielectric barrier discharge (SDBD) reactor as an ozone generator to inactivate Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA) in an open water system. Experimental details are provided for ozone generation technique, mixing method, ozone concentrations in air and water, and input energy required to produce adequate ozone concentrations for bacterial inactivation in a contaminated, open water system. Specifically, an active plasma module (APM) reactor system of size 48 cubic centimeters, weighing 55 grams, with a maximum ozone yield of 68.6 g/KWh was used in atmospheric conditions as the source of ozone along with an air pump and a diffusion stone for mixing the ozone in water. Over 4-log reduction in P. aeruginosa concentration was achieved in 4 minutes with 0.1 mg/L ozone concentration in an open water system using 8.8 ± 1.48 J input energy. Also, over 5-log reduction in MRSA concentration was achieved in 2 minutes with 0.04 mg/L ozone concentration in an open water system using 4.4 ± 0.74 J input energy.

Synergistic effect of ozonated and electrolyzed water on the inactivation kinetics of Escherichia coli on goat meat

“…No natural microbiota was found on the surface of noninoculated samples (negative control). Because of the differences in the initial population of E. coli K12 for different experiments, a conversion factor (concentration/initial concentration) was used to adjust the log reduction values (Choudhury, Portugal, Mastanaiah, Johnson, & Roy, ). Log reductions increased from 0.22 ± 0.12 to 0.53 ± 0.21, 0.50 ± 0.20 to 0.86 ± 0.34, and 0.43 ± 0.23 to 0.74 ± 0.30 CFU/ml with OW, AcEW, and AlEW treatments, respectively, with increased treatment time (Table ).…”

Rapid inactivation of SARS-CoV-2 with ozone water

“…The aim of this study was to clarify the inactivating effect of ozone water on SARS-CoV-2 by its concentration and contact time. Although ozone water is known to have an inactivating effect on several microorganisms [13, 15, 16], whether ozone water is also effective against SARS-CoV-2 has not been reported so far. In addition, the mode of action of ozone water, including concentration and duration of treatment, should be investigated for its use to prevent fomite infection.…”

“…A variety of disinfectants can reduce viral viability with a contact time of at least 30 seconds or more [10]. Among hand rub solutions, ozone water is one of the promising candidates, because it is known that ozone water has an inactivating effect on some microorganisms [13][14][15][16] and is harmless to human beings [17,18]. Furthermore, the production of highconcentration ozone water has been facilitated by the advent of electrolytic ozone generators [19].…”

Application of dielectric barrier discharge for improving food shelf life and reducing spoilage

“…1 b) by applying an alternating potential difference between the top and bottom electrodes. Details of this DBD reactor can be found in previous studies published by our group on ozone water disinfection 24 .

Figure 1 Dielectric Barrier Discharge reactor used for ozone generation ( a ) reactor showing exposed and ground electrode separated by a dielectric barrier, ( b ) plasma formed around exposed electrode when reactor is powers and ( c ) dimensions of the electrode configuration used in the reactor.

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“…These input conditions generate approximately 7 kVpp (peak to peak voltage) at the output. The DBD reactor run by the APM uses a power of 2.2 ± 0.37 W 24 . A graphical explanation of this electrical system is presented in Fig.…”