Properties of essential oils absorbed on the surface of cardboard pieces after using atmospheric-pressure plasma treatments to develop long-lasting Varroa miticides in honeybees (Apis mellifera).

The ectoparasitic mite, Varroa destructor is the most serious widespread pest of managed honeybees (Apis mellifera). Several acaricide products, which include essential oils, have been proposed for mite control. In this study, we aimed to apply atmospheric-pressure plasma to modify a cardboard piece surface in order to prolong the delivery of essential oils for controlling Varroa in honeybee colonies. Absorption capacity, release rates and evaporation rates of essential oils were determined. Cardboard piece showed a higher absorption capacity of cinnamon compared to citronella and clove. Surface modification of cardboard pieces using argon plasma at different gas flow rates and treatment durations, significantly affected the absorption of clove oil. Additionally, the release rate of cinnamon, citronella and clove was significantly enhanced after argon plasma treatments. Evaporation of cinnamon was dramatically increased by plasma treatment at 6-h of incubation. The highest evaporation rate was obtained by plasma-treated cardboard piece at a gas flow rate of 0.5 Lpm for 60 s (0.2175 ± 0.0148 µl/g•h). Efficiency of plasma-treated cardboard piece, impregnated with essential oils, was also investigated for Varroa control in honeybee colonies. In the first experiment, formic acid 65% (v/v) showed the highest efficiency of 90.60% and 81.59% with the percent of mite infestation was 0.23 ± 0.13% and 0.47 ± 0.19% at 21 and 35 days, respectively after treatment. The efficacy of cardamon oil (5% (v/v)) delivered using plasma-treated cardboard pieces was 57.71% (0.70 ± 0.16% of mite infestation) at day 21 of experiment. However, the delivery of cardamon oil at the concentration of 1% and 5% (v/v) by untreated cardboard piece had 16.93% and 24.05% of efficacy to control mites. In the 2nd experiment, the application of plasma-treated cardboard pieces impregnated with 5% (v/v) clove oil induced a 38.10% reduction in the population of Varroa mites followed by 5% (v/v) of cardamon with 30% efficiency. Although, the infestation rate of Varroa in colonies was not significant different between treatments, essential oils delivered using plasma-treated cardboard pieces tended to decrease Varroa population in the treated colonies. Hence, atmospheric-pressure plasma for the modification of other materials, should be further investigated to provide alternative control treatment applications against honeybee mites.

In silico ecotoxicity assessment of pharmaceutical residues in wastewater following oxidative treatment.

Advanced oxidation processes such as thermal plasma activation and UV-C/H2O2 treatment are considered as applications for the degradation of pharmaceutical residues in wastewater complementary to conventional wastewater treatment. It is supposed that direct oxidative treatment can lower the toxicity of hospital sewage water (HSW). The aim of this study was to predict the ecotoxicity for three aquatic species before and after oxidative treatment of 10 quantified pharmaceuticals in hospital sewage water. With the application of oxidative chemistry, pharmaceuticals are degraded into transformation products before reaching complete mineralization. To estimate the potential ecotoxicity for fish, Daphnia and green algae ECOSAR quantitative structure-activity relationship software was used. Structure information from pristine pharmaceuticals and their oxidative transformation products were calculated separately and in a mixture computed to determine the risk quotient (RQ). Calculated mixture toxicities for 10 compounds found in untreated HSW resulted in moderate-high RQ predictions for all three aquatic species. Compared to untreated HSW, 30-min treatment with thermal plasma activation or UV-C/H2O2 resulted in lowered RQs. For the expected transformation products originating from fluoxetine, cyclophosphamide and acetaminophen increased RQs were predicted. Prolongation of thermal plasma oxidation up to 120 min predicted low-moderate toxicity in all target species. It is anticipated that further degradation of oxidative transformation products will end in less toxic aliphatic and carboxylic acid products. Predicted RQs after UV-C/H2O2 treatment turned out to be still moderate-high. In conclusion, in silico extrapolation of experimental findings can provide useful predicted estimates of mixture toxicity. However due to the complex composition of wastewater this in silico approach is a first step to screen for ecotoxicity. It is recommendable to confirm these predictions with ecotoxic bioassays.

Deciphering morphological and biochemical responses of Salvia leriifolia to seed cold plasma treatment, priming, and foliar spraying with nano-salicylic acid.

The pretreatment of seeds with cold plasma (CP) (0 and 100 w for 240 s), and salicylic acid priming (SA) (0 and 2 mM normal and nano form), and foliar spraying of SA at the six-leaf stage (0 and 2 mM normal and nano form) of Salvia leriifolia plants in field condition was studied. Compared to the control plants of S. leriifolia, the results showed that CP + both forms of SA priming + nano-SA spraying increased plant height, leaf length, plant dry weight, total phenol, and the activities of phenylalanine ammonia-lyase (PAL) and tyrosine ammonia-lyase (TAL) enzymes. The chlorophyll a and b contents in all treated plants remained either unchanged or decreased when compared to the control. The highest PAL activity was obtained in CP-free + hydro-priming + nano-SA foliar spraying. The highest content of caffeic acid was achieved in CP + SA priming + SA foliar spraying in the leaf. The maximum contents of rosmarinic and salvianolic acid were obtained in the control plants. In conclusion, CP and nano-SA can increase PAL and TAL activity and total phenol accumulation in S. leriifolia plants, but not rosmarinic and salvianolic acid contents. Other phenolic compound enzymes and their production require further study.

Enhancing Bioactivity and Conjugation in Green Coffee Bean (Coffea arabica) Extract through Cold Plasma Treatment: Insights into Antioxidant Activity and Phenolic-Protein Conjugates.

Cold plasma technology is gaining attention as a promising approach to enhancing the bioactivity of plant extracts. However, its impact on green coffee bean extracts (GCBEs) still needs to be explored. In this study, an innovative underwater plasma jet system was employed to investigate the effects of cold plasma on Coffea arabica GCBEs, focusing on the conjugation reflected by the change in composition and bioactivity. The DPPH radical scavenging antioxidant activity exhibited a gradual increase with plasma treatment up to 35 min, followed by a decline. Remarkably, at 35 min, the plasma treatment resulted in a significant 66% increase in the DPPH radical scavenging activity of the GCBE. The total phenolic compound content also displayed a similar increasing trend to the DPPH radical scavenging activity. However, the phenolic profile analysis indicated a significant decrease in chlorogenic acids and caffeine. Furthermore, the chemical composition analysis revealed a decrease in free amino acids, while sucrose remained unchanged. Additionally, the SDS-PAGE results suggested a slight increase in protein size. The observed enhancement in antioxidant activity, despite the reduction in the two major antioxidants in the GCBE, along with the increase in protein size, might suggest the occurrence of conjugation processes induced by plasma, particularly involving proteins and phenolic compounds. Notably, the plasma treatment exhibited no adverse effects on the extract's safety, as confirmed by the MTT assay. These findings indicate that cold plasma treatment holds significant promise in improving the functional properties of GCBE while ensuring its safety. Incorporating cold plasma technology into the processing of natural extracts may offer exciting opportunities for developing novel and potent antioxidant-rich products.

On the evaluation of the antimicrobial effect of grape seed extract and cold atmospheric plasma on the dynamics of Listeria monocytogenes in novel multiphase 3D viscoelastic models.

The demand for products that are minimally processed and produced in a sustainable way, without the use of chemical preservatives or antibiotics have increased over the last years. Novel non-thermal technologies such as cold atmospheric plasma (CAP) and natural antimicrobials such as grape seed extract (GSE) are attractive alternatives to conventional food decontamination methods as they can meet the above demands. The aim of this study was to investigate the microbial inactivation potential of GSE, CAP (in this case, a remote air plasma with an ozone-dominated RONS output) and their combination against L. monocytogenes on five different 3D in vitro models of varying rheological, structural, and biochemical composition. More specifically, we studied the microbial dynamics, as affected by 1 % (w/v) GSE, CAP or their combination, in three monophasic Xanthan Gum (XG) based 3D models of relatively low viscosity (1.5 %, 2.5 % and 5 % w/v XG) and in a biphasic XG/Whey Protein (WPI) and a triphasic XG/WPI/fat model. A significant microbial inactivation (comparable to liquid broth) was achieved in presence of GSE on the surface of all monophasic models regardless of their viscosity. In contrast, the GSE antimicrobial effect was diminished in the multiphasic systems, resulting to only a slight disturbance of the microbial growth. In contrast, CAP showed better antimicrobial potential on the surface of the complex multiphasic models as compared to the monophasic models. When combined, in a hurdle approach, GSE/CAP showed promising microbial inactivation potential in all our 3D models, but less microbial inactivation in the structurally and biochemically complex multiphasic models, with respect to the monophasic models. The level of inactivation also depended on the duration of the exposure to GSE. Our results contribute towards understanding the antimicrobial efficacy of GSE, CAP and their combination as affected by robustly controlled changes of rheological and structural properties and of the biochemical composition of the environment in which bacteria grow. Therefore, our results contribute to the development of sustainable food safety strategies.

Establishment of a desirable dose using neutral argon plasma to eradicate miliary peritoneal implants: A phase I/II controlled trial.

INTRODUCTION: Neutral argon plasma (NAP) system could meet the requirements to achieve oncological cytoreduction of peritoneal carcinomatosis with miliary lesions, minimizing the associated morbidity. This phase I/II trial aims to establish the desirable dose that is safe and effective in eliminating tumor cells with lower penetration. METHODS: Patients diagnosed with different origins for peritoneal carcinomatosis and miliary implants were selected for the study. The safe and potentially effective dose (desirability) of NAP was evaluated according to three factors: distance (mm), application time (s) and power (%), to evaluate the response variables such as the presence of tumor cells (Y/N) and the depth of penetration. RESULTS: Ten patients and 120 samples were evaluated and treated with NAP. There was no vascular or organ injury intraoperative using a pre-established dose of 100% (coagulation mode) at a distance of 2-3 cm. The distance was found to be correlated with the presence of the tumor cells in ex-vivo analysis, with an OR of 15.4 (4.0-111.4). The time and energy used were protective factors to eliminate tumor cells with an OR of 0.4 (0.1-0.9) and 0.8 (0.8-0.9), respectively. The safest and most effective desirability results were as follows i) energy 80% during 2-4 s with a distance of 2 cm (0.89), and ii) energy 100% during 2-4 s with a distance of 3 cm (0.90). CONCLUSIONS: The use of NAP during a CRS and HIPEC is safe and effective for eradicating tumor cells on the peritoneal surface at suggested doses of energy, distance and duration. TRIAL IDENTIFICATION: ClinicalTrials.gov Identifier: NCT04904042.

Effect of dielectric barrier discharge (DBD) cold plasma-activated water pre-treatment on the drying properties, kinetic parameters, and physicochemical and functional properties of Centella asiatica leaves.

Centella asiatica L. (CA) is a medicinal plant that gained significant commercial and research interest because of its bioactive compounds, which have functional properties such as antioxidant activity. However, it must be dried before use to improve its shelf life and prepare it for food and pharmaceutical applications. Therefore, in this investigation CA leaves were pre-treated with blanching and cold plasma activated water (CPAW), followed by recirculatory hot air and vacuum drying at 40, 50, and 60 °C. Vacuum-drying took 150-720 min, while hot-air drying took 60-180 min to dry. Page and Logarithmic models best fit for leaf drying kinetics, according to AIC, with R2 between 0.966 and 0.999 and RMSE between 0.001 and 0.069. CPAW pre-treatment increased leaf quality more than blanching in vacuum drying. Drying leaves at 40 °C boosted antioxidants (4021.462 µg TE (g dw)-1 and 3.356 mg GAEAC (g dw)-1), TPC (35.049 mg GAE (g dw)-1), and TFC (311.274 mg QE (g dw)-1) and is recommended. Vacuum-drying with CPAW pre-treatment preserved leaf microstructure better than hot-air drying. This study illuminates CA leaf drying behaviour and allow mass production without damaging bioactive components. These results could be used as a roadmap for future technological advances that will make it possible to use the bioactive components of CA in food formulation.

Thermal plasma potential to remediate soil contaminated with diesel.

Petroleum hydrocarbons (PHCs) are recognized as one of the major soil contaminants causing negative environmental impact. Thereby, PHCs remediation from the soil is essential. Hence, this experimental study aimed to assess the potential of thermal water vapor and air plasmas to remediate soil contaminated with habitually used PHCs - diesel. The impact of contaminant content in the soil on the remediation process also was estimated. The results of this research demonstrated that 99.9% contaminant removal efficiency was received proceeding diesel contaminated soil remediation in the environment of the thermal plasma in defiance of whether water vapor or air was employed as a plasma-forming gas. Moreover, the soil's contaminant content (80-160 g/kg) did not influence its' removal efficiency. The soil de-pollution process also caused the decomposition of the soils' natural carbon reserves since carbon content decreased from an initial 9.8 wt% in the clean soil to 3-6 wt% in the remediated soil. Furthermore, PHCs - diesel was decomposed into producer gas mainly consisting of H2, CO (also known as synthesis gas) and CO2. Thus, the thermal plasma offers a way not only to de-pollute the soil but also to reuse the PHCs present in the soil by breaking it down into gaseous products that can further be used to meet human needs.

Canal pretreatment using cold atmospheric argon plasma, chitosan and Chlorine p6 activated by photodynamic therapy with EDTA as a final irrigant on the pushout bond strength of fiber post.

AIMS: To evaluate the effect of contemporary root canal irrigants i.e., Cold atmospheric argon plasma (CAAP), Chlorine p6 (Clp6), and chitosan on the push-out bond strength (PBS) of glass fiber post (GFP) and marten hardness (MH) of root canal dentin compared to NaOCl+EDTA. MATERIALS AND METHODS: The anatomic crown of sixty human mandibular premolars was removed by transversal section till cement-enamel junction (CEJ). Root canals were prepared and canals were dried and obturated using gutta-percha points and AH plus sealer. Post space was prepared and specimens were arbitrarily divided into four groups based on the post-space irrigation. (n = 15) Group 1: 5.25% NaOCl + 17% EDTA, Group 2: CAAP + 17% EDTA, Group 3: Chitosan + 17% EDTA and Group 4: Clp6 + 17% EDTA. For MH evaluation five samples from each disinfected group were taken and MH was assessed with the help of an ultra microhardness tester. GFP was cemented using self-etch dual cure cement on the remaining 10 samples from each group. Samples were vertically planted in acrylic resin blocks 1 mm thick slices were subjected to push-out testing and failure mode analysis using a universal testing machine and Stereomicroscope. ANOVA and Tukey multiple comparison tests were used to compare the means of bond integrity attained (p = 0.05). RESULTS: The maximum values of PBS and MH were displayed in group 1 (5.25% NaOCl + 17% EDTA) specimens. However, group 3 exhibited the minimum values of bond strength and MH scores. Intergroup comparison analysis revealed that group 2, group 3, and group 4 displayed comparable outcomes of PBS and MH (p > 0.05). The cervical and middle third of group 1 specimens displayed a cohesive type of failure. However, the apical section of group 1 and other tested groups exhibited the adhesive type of failure. CONCLUSION: Canal irrigation with 5.25% NaOCl and 17% EDTA appears to be better in terms of improving the bond integrity of fiber posts with no compromise in MH of the dentin as compared to the contemporary irrigant used.

Comparison of Physicochemical Properties of Silver and Gold Nanocomposites Based on Potato Starch in Distilled and Cold Plasma-Treated Water.

Nanometal-containing biocomposites find wide use in many industries and fields of science. The physicochemical properties of these materials depend on the character of the polymer, the size and shape of the metallic nanoparticles, and the interactions between the biopolymer and the nanoparticles. The aim of the work was to synthesise and study the effect of plasma-treated water on the properties of the obtained metallic nanoparticles as well as the physicochemical and functional properties of nanocomposites based on potato starch. The metallic nanoparticles were synthesised within a starch paste made in distilled water and in distilled water exposed to low-temperature, low-pressure plasma. The materials produced were characterised in terms of their physicochemical properties. Studies have shown that gold and silver nanoparticles were successfully obtained in a matrix of potato starch in distilled water and plasma water. SEM (Scanning Electron Microscopy) images and UV-Vis spectra confirmed the presence of nanosilver and nanosilver in the obtained composites. On the basis of microscopic images, the size of nanoparticles was estimated in the range from 5 to 20 nm for nanoAg and from 15 to 40 nm for nanoAu. The analysis of FTIR-ATR spectra showed that the type of water used and the synthesis of gold and silver nanoparticles did not lead to changes in the chemical structure of potato starch. DLS analysis showed that the nanoAg obtained in the plasma water-based starch matrix were smaller than the Ag particles obtained using distilled water. Colour analysis showed that the nanocomposites without nanometals were colourless, while those containing nanoAg were yellow, while those with nanoAu were dark purple. This work shows the possibility of using plasma water in the synthesis of nanometals using potato starch, which is a very promising polysaccharide in terms of many potential applications.

Effect of ultrasound-assisted cold plasma pretreatment on cell wall polysaccharides distribution and extraction of phenolic compounds from hyssop (Hyssopus officinalis L.).

Hyssopus officinalis L (Hyssop) is a good source of phenolic compounds. However, conventional methods for extraction of these compounds typically take a long time and have relatively low recovery rates. This study focused on cold atmospheric plasma (CAP) pretreatment and investigated its effects on the ultrasound-assisted extraction (UAE) of phenolic compounds from hyssop. Hyssop was treated at dielectric barrier discharge plasma with air and nitrogen gases for 5, 10, and 15 min. Optical emission spectroscopy was used to evaluate present active species in the plasma. The water contact angle changes, cell wall polysaccharides distribution, and structural variations of the treated samples were determined after treatment. Antioxidant activity and total phenolic contents (TPC) of the extracts were also evaluated. The results showed that CAP treatment reduced the contact angle making surface more hydrophilic. Compared with hyssop, overall no significant changes in the basic structure of all treated samples or the formation of new functional groups were recognized. In addition, CAP pretreatment before UAE increased the antioxidant activity of extracts according to the FRAP assay than the un-pretreated sample and conventional solvent extraction method. Also, TPC increased in samples treated with nitrogen plasma.

Cold plasma treatment with alginate oligosaccharide improves the digestive stability and bioavailability of nutrient-delivered particles: An in vitro INFOGEST gastrointestinal study.

To improve the stability and bioavailability of the delivered hydrophobic nutrients, the zein-based delivery system was modified by alginate oligosaccharide (AOS), cold plasma (CP) treatments, and synergistically. The digestive behavior of each was investigated in an INFOGEST static in vitro digestion model. The results showed that AOS and CP treatments and their synergistic effects improved the dispersion and stability of the delivery system, leading to a more concentrated particle size distribution and higher particle surface charge. Both CP treatments and AOS increased the release rate of Curcumin (Cur) at small intestine (11.8 % to 20.5 % and 11.8 % to 24.64 %, respectively), and the synergistic effect was higher (11.8 % to 43.84 %). The wall material modified showed a higher encapsulation efficiency of Cur (52.83 % to 85.17 %). Cur release rate measurements showed that the wall material modified could have a positive effect on the slow release of Cur. SDS-page electrophoresis revealed that the slow release was due to the enhanced resistance of wall material to digestive fluids. Thus, treatment with AOS and CP treatments, and the synergism are suitable for modifying zein-based delivery systems for the encapsulation, stabilization, and slow release of hydrophobic nutrients during digestion in the field of functional foods.

Rheological performance of film-forming solutions and barrier properties of films fabricated from cold plasma-treated high methoxyl apple pectin and crosslinked by Ca2+: Impact of plasma treatment voltage.

Sustainable and "green" technologies, such as cold plasma are gaining attention in recent times for improving the functional properties of hydrocolloids. Chemical modifications of hydrocolloids require several chemicals and solvents, which are not environment-friendly. The major objective of the study was to understand the impact of plasma treatment (170-230 V|15 min) on the rheology of film-forming solutions (FFS) and the barrier properties of pectin films. The film-forming properties of plasma-treated pectin were investigated in the presence of two plasticizers, namely, glycerol and polyethylene glycol (PEG) 400. The effects of cross-linking by CaCl2 on the rheology of FFS and barrier properties of the films were discussed. A voltage-dependent decrease in the apparent viscosity of FFS was observed. The viscoelastic properties of the FFS were enhanced due to cross-linking. Glycerol exhibited a better plasticizing effect than PEG. Cross-linking and increasing voltage synergistically contributed towards lower oxygen and carbon dioxide transmission rates. The moisture sorption rate and capacity of the films increased with the voltage of the treatment. The resistance to extension of the films made from glycerol and PEG decreased with voltage, with no significant change in extensibility. On the other hand, the cross-linking by Ca2+ and plasma treatment enhanced the resistance to extension for the films made from both the plasticizers. While the increasing hydrophilicity and opacity of the films were a major drawback of plasma modification, the increase in UV barrier property of the films was an advantage of the modification.

Extraction of anthocyanins from haskap using cold plasma-assisted enzyme.

BACKGROUND: Haskap berries (Lonicera caerulea L.) are rich in anthocyanins. Cold plasma-assisted enzyme method (CPEM) is an innovative method for green extraction of anthocyanins, which was optimized by an artificial neural network-genetic algorithm (ANN-GA) to maximize the yield. In this study, seven factors were screened using by Plackett-Burman design based on single-factor experiments and optimized by ANN-GA. RESULTS: The results showed that the maximum total anthocyanin content (TAC, 42.45 ± 0.25 g cyanidin-3-glucoside equivalent (C3G) kg-1 dry weight, DW) was obtained under optimal pretreatment power of 192 W, pretreatment time of 29 s and liquid-to-solid ratio of 39 mL g-1 . Cleavage and porosity appeared on the surface of the treated sample. The active ingredients and antioxidant capacity of the CPEM extracts were identified by ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Compared with other extraction technologies, CPEM presents the advantages of shortening the extraction time, reducing the solvent volume, and significantly increasing active ingredients and antioxidant activity. CONCLUSION: The ANN-GA has better predictive and higher accuracy than the response surface methodology (RSM) model and is more suitable for optimizing the CPEM by greatly improving the process yield and the utilization of biomass, thus contributing to the sustainability of the agri-food chain. © 2022 Society of Chemical Industry.

Sage extracts obtained with cold plasma improves beef quality.

The aim of the study was to verify the effect of sage extracts obtained using cold plasma on the quality of ground beef. Patties with a different content of sage extracts (0.05% and 0.075%) obtained either by conventional extraction (S0.05, S.0.075) or with cold plasma assistance (SP0.05, SP0.075) were packed under a modified atmosphere (80%O2) and stored in cold conditions for 8 days. Sage extracts addition had no impact on pH, weight loss, colour, content of each myoglobin form, texture, aroma and overall acceptability of raw meat measured on the last storage day (P < 0.05). However, lipid oxidation was inhibited the most in meat with the highest share of sage extract obtained using cold plasma (P < 0.05). This group was also characterized by the highest amount of n-3 fatty acids at the end of storage (P < 0.05). Moreover, the addition of sage at 0.075% prevented hexanal formation in samples. Thus, cold plasma extracts may be introduced in the meat industry.

Plasma treatment effects on destruction and recovery of Porphyromonas gingivalis biofilms.

The objective of this study was to investigate the treatment effects of non-thermal atmospheric gas plasmas (NTAP) on destruction and the recovery (or re-colonization) of Porphyromonas gingivalis (P. gingivalis) in biofilms. P. gingivalis is a well-known keystone periodontal pathogen strongly associated with periodontal diseases, especially periodontitis. P. gingivalis biofilms were formed on stainless steel coupons and treated for 1, 2, and 5 minutes by NTAP of pure argon gas and argon+oxygen gas mixture. MTT assay, colony forming unit (CFU) counting assay and confocal laser scanning microscopy (CLSM) were used to assess the destruction efficiency. In addition, the plasma treated biofilms were re-cultured in the medium supplemented with antibiotics and oxidative stress sources to determine the synergy of the NTAP with other antimicrobial agents. The results showed the plasma treatment could result in 2.7 log unit reduction in bacterial load. The recovered biofilm CFU with NTAP treatment combined with sub minimal inhibition concentration of amoxicillin was 0.33 log units less than the biofilm treated with amoxicillin alone. The recovered biofilm CFU in NTAP groups was about 2.0 log units less than that in the untreated controls under H2O2 treatment. There was approximately 1.0 log unit reduction of biofilm CFU in plasma treated biofilm compared with untreated control under paraquat treatment. The plasma treated biofilms exhibited less resistance to amoxicillin and greater susceptibility to hydrogen peroxide (H2O2) and paraquat, suggesting that NTAP may enhance biofilm susceptibility to host defense. These in vitro findings suggested that NTAP could be a novel and effective treatment method of oral biofilms that cause periodontal diseases.

Cold Atmospheric Plasma Activates Selective Photothermal Therapy of Cancer.

Due to the body's systemic distribution of photothermal agents (PTAs), and to the imprecise exposure of lasers, photothermal therapy (PTT) is challenging to use in treating tumor sites selectively. Striving for PTT with high selectivity and precise treatment is nevertheless important, in order to raise the survival rate of cancer patients and lower the likelihood of adverse effects on other body sections. Here, we studied cold atmospheric plasma (CAP) as a supplementary procedure to enhance selectivity of PTT for cancer, using the classical photothermic agent's gold nanostars (AuNSs). In in vitro experiments, CAP decreases the effective power of PTT: the combination of PTT with CAP at lower power has similar cytotoxicity to that using higher power irradiation alone. In in vivo experiments, combination therapy can achieve rapid tumor suppression in the early stages of treatment and reduce side effects to surrounding normal tissues, compared to applying PTT alone. This research provides a strategy for the use of selective PTT for cancer, and promotes the clinical transformation of CAP.

Effect of atmospheric cold plasma (ACP) on chlorine-adapted Salmonella enterica on spring onion.

One of the main drawbacks of chlorine disinfectants is the emergence of chlorine adapted (CA) or resistant microbial cells. This research aimed to investigate the effect of chlorine adaptation on resistance of Salmonella enterica upon atmospheric cold plasma (ACP) application at different voltages (6, 8 and 11 kV) and times (5, 10 and 15 min). Due to higher conversion efficiency and reduced dielectric barrier discharge power consumption, this method was used for cold plasma generation in this study. A higher lethality effect was observed from a higher voltage and longest times (11 kV-15 min) on CA S. enterica than on non-CA (P < 0·05). Still, it induced higher percentages of injured cells in CA (58·77%) than on non-CA (0·61%) (P < 0·05). The highest ACP effect on the inactivation of the indigenous natural flora of onion leaves was observed at the lowest voltage (P < 0·05). More than 3 log CFU/g reduction (P < 0·05) was observed at 6 kV after 5 and 10 min. ACP reduced CA and non-CA S. enterica cells on onion leaf surface to a lower extent than pure-treated cells in broth media. Nevertheless, similar to broth media, a high percentage of injury (61·03%) was induced on CA cells at higher voltage (11 kV-10 min) compared to non-CA (2·15%) (P < 0·05). Biofilm results revealed ACP application (6 kV-5 min) reduced average ODs in CA and non-CA cells (P < 0·05). Chlorine adaptation and ACP treatment influenced the antibiotic resistance pattern according to applied voltage, time and antibiotic type. The finding showed despite the highest lethality of high voltages and long times (11 kV-15 min), given the high percentages of injured cells, lower voltages may offer acceptable inactivation of pathogenic bacteria with lower injury induction. In conclusion, ACP has the potential ability to eliminate CA cells of S. enterica, which are predominant in fresh-cut vegetable outbreaks.

Molecular Mechanisms for Anti-aging of Low-Vacuum Cold Plasma Pretreatment in Caenorhabditis elegans.

Cold plasma pretreatment has the potential of anti-aging. However, its molecular mechanism is still not clear. Here, cold plasma pretreatment was firstly used to investigate the anti-aging effects of Caenorhabditis elegans using transcriptomic technique. It showed that the optimal parameters of discharge power, processing time, and working pressure for cold plasma pretreatment were separately 100 W, 15 s, and 135 Pa. The released 0.32 mJ/cm2 of the moderate apparent energy density was possibly beneficial to the strong positive interaction between plasma and C. elegans. The longest lifespan (13.67 ± 0.50 for 30 days) was obviously longer than the control (10.37 ± 0.46 for 23 days). Furthermore, compared with the control, frequencies of head thrashes with an increase of 26.01% and 37.31% and those of body bends with an increase of 33.37% and 34.51% on the fourth and eighth day, respectively, indicated movement behavior was improved. In addition, the variation of the enzyme activity of superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) hinted that the cold plasma pretreatment contributed to the enhanced anti-aging effects in nematodes. Transcriptomics analysis revealed that cold plasma pretreatment resulted in specific gene expression. Anatomical structure morphogenesis, response to stress, regulation of biological quality, phosphate-containing compound metabolic process, and phosphorus metabolic process were the most enriched biological process for GO analysis. Cellular response to heat stress and HSF1-dependent transactivation were the two most enriched KEGG pathways. This work would provide the methodological basis using cold plasma pretreatment and the potential gene modification targets for anti-aging study.

Cold atmospheric plasmas target breast cancer stemness via modulating AQP3-19Y mediated AQP3-5K and FOXO1 K48-ubiquitination.

Cold atmospheric plasma (CAP) is selective against many cancers with little side effect, yet its molecular mechanism remains unclear. Through whole transcriptome sequencing followed by assays in vitro, in vivo and using clinical samples, we propose CAP as a promising onco-therapy targeting cancer stemness via the AQP3/FOXO1 axis. CAP-generated reactive species penetrated cells via AQP3 and suppressed RPS6KA3, a shared kinase of AQP3 and FOXO1. Reduced AQP3-19Y phosphorylation suppressed SCAF11-mediated AQP3-5K K48-ubiquitination that led to sabotaged FOXO1 stability. Inhibited FOXO1 phosphorylation retarded its regulatory activities in maintaining cancer stemness including ALDH1 and IL6. Enhanced anti-cancer efficacy was observed through combining CAP with Atorvastatin in vitro and in vivo. We propose CAP as a 'selective' onco-therapeutic against cancer stemness, with the AQP3/FOXO1 axis being one molecular mechanism. We report SCAF11 as an E3 ubiquitin ligase of both AQP3 and FOXO1, identify AQP3-5K as an AQP3 K48-ubiquitination site, and emphasize the essential role of AQP3-19Y in this process. We reposition Atorvastatin into the onco-therapeutic portfolio by synergizing it with CAP towards enhanced efficacy. We anticipate the efficacy of CAP in targeting malignancies of high stemness alone or as an adjuvant therapy towards the hope of ultimate cancer cure.