Rapid eradication of bacterial phytopathogens by atmospheric pressure glow discharge generated in contact with a flowing liquid cathode

Abstract

Diseases caused by phytopathogenic bacteria are responsible for significant economic losses, and these bacteria spread through diverse pathways including waterways and industrial wastes. It is therefore of high interest to develop potent methods for their eradication. Here, antibacterial properties of direct current atmospheric pressure glow discharge (dc-APGD) generated in contact with flowing bacterial suspensions were examined against five species of phytopathogens. Complete eradication of Clavibacter michiganensis subsp. sepedonicus, Dickeya solani, and Xanthomonas campestris pv. campestris from suspensions of OD ≈ 0.1 was observed, while there was at least 3.43 logarithmic reduction in population densities of Pectobacterium atrosepticum and Pectobacterium carotovorum subsp. carotovorum. Analysis of plasma-chemical parameters of the dc-APGD system revealed its high rotational temperatures of 2,300 ± 100 K and 4,200 ± 200 K, as measured from N and OH molecular bands, respectively, electron temperature of 6,050 ± 400 K, vibrational temperature of 4000 ± 300 K, and high electron number density of 1.1 × 10 cm . In addition, plasma treatment led to formation of numerous reactive species and states in the treated liquid, including reactive nitrogen and oxygen species such as NO , NH, H O , O , O, and OH. Further examination revealed that bactericidal activity of dc-APGD was primarily due to presence of these reactive species as well as to UVA, UVB, and UVC irradiation generated by the dc-APGD source. Plasma treatment also resulted in an increase in temperature (from 24.2 to 40.2 °C) and pH (from 6.0 to 10.8) of bacterial suspensions, although these changes had minor effects on cell viability. All results suggest that the newly developed dc-APGD-based system can be successfully implemented as a simple, rapid, efficient, and cost-effective disinfection method for liquids originating from different industrial and agricultural settings.

Activation of the Normal Human Skin Cells by a Portable Dielectric Barrier Discharge-Based Reaction-Discharge System of a Defined Gas Temperature

“…3 ) [49]. The above-mentioned orange VO 2+ 3 cation, showing a maximum absorbance at 450 nm, was obtained as a result of the reaction between the H 2 O 2 molecules with ammonium metavanadate (NH 4 VO 3 ) in the medium of 0.58 mol L −1 H 2 SO 4 .…”

“…In addition, other optical temperatures such as the T exc , the T vib , and the T rot , and the n e were assessed for He-DBD operated under the optimal conditions. The T exc of H atoms was determined using the twoline method, using 656.20 nm (H α line) and 486.13 nm (H β line) emission lines [49].The T vib of the OH molecules was evaluated based on two OH (A-X) molecular bands, i.e., the (1-0) and (0-0) transitions. In turn, experimentally measured OH molecular bands in the range within 280-320 nm were fitted with those simulated using the Lifbase software at different values of the T vib [50].…”

Plant Disease Control by Non-Thermal Atmospheric-Pressure Plasma

“…Compared to that, the treatment of bacteria causing plant diseases has been relatively less explored in the application of plasma ( Table 1). Several studies demonstrate that plasma treatment of phytopathogenic bacterial suspension can reduce the number of viable bacteria in a time-dependent manner (Moreau et al, 2007;Mráz et al, 2014;Toyokawa et al, 2017;Motyka et al, 2018). Gliding arc discharge can effectively inactivate the potato pathogen Erwinia carotovora by altering the bacterial membrane (Moreau et al, 2007).…”

“…campestris, Pectobacterium atrosepticum, and Pectobacterium carotovorum subsp. carotovorum (Motyka et al, 2018). The viability of X. campestris pv.…”

Multivariate Optimization of the FLC-dc-APGD-Based Reaction-Discharge System for Continuous Production of a Plasma-Activated Liquid of Defined Physicochemical and Anti-Phytopathogenic Properties

“…So far, plasma activated waters (PAWs) have been tested against Colletotrichum gloeosporioides [ 35 ] causing bitter rot in numerous crops, Xanthomonas vesicatoria responsible for the leaf spot on tomatoes [ 36 ], Colletotrichum alienum being a post-harvest pathogen of avocado [ 37 ], and Penicillium italicum triggering blue and green molds on citrus fruits [ 38 ]. Concerning SRP, to the best of our knowledge, solely a direct impact of plasma generated either by electric discharges in a gliding arc reactor in a stationary phase [ 39 ] or a direct current atmospheric pressure glow discharge obtained in contact with a flowing cathode [ 40 ] has been reported as an effective method to combat these pests.…”