Effect Of Cold Plasma Research Articles

Optimizing anthocyanins extraction and the effect of cold plasma treatment on the anti‐aging potential of purple glutinous rice (Oryza sativa L.) extract

AbstractBackground and objectivesThe pericarp of color rice is a rich source of anthocyanins conferring several health benefits. The present study aimed to systemically optimize anthocyanins extraction from Thai purple glutinous rice and to elucidate the effect of cold plasma on the anti‐aging effect of the extract.FindingsAntioxidant effects and phytochemical constituents of the extracts from three Thai purple glutinous rice varieties including Doi Saket, Phayao, and Luem Pua were elucidated. Cyanidin‐3‐O‐glucoside (CNG) was a major compound in all varieties. Besides, Luem Pua rice extract presented the strongest antioxidation owing to its highest total phenolic and CNG contents. The optimized method for extracting CNG, which was proceeded by 2‐level full factorial design, used deionized (DI) water with pH 2.0 and temperature 150°C. Moreover, the cold plasma‐treated Luem Pua rice offered a five‐fold higher amount of CNG compared to the untreated sample with a significantly stronger anti‐aging potential.ConclusionsOur study provided the optimized method for CNG extraction from purple rice. Additionally, cold plasma potentially enhanced the anti‐aging property of the extract.Significance and noveltyThe contributions of the extracting factors on antioxidation and anthocyanins content were statistically elucidated, and the novel performance of cold plasma on biological properties of the plant materials was demonstrated.

Biomolecules as Model Indicators of In Vitro and In Vivo Cold Plasma Safety.

The potential applications for cold plasma in medicine are extensive, from microbial inactivation and induction of apoptosis in cancer cells to stimulating wound healing and enhancing the blood coagulation cascade. The safe bio-medical application of cold plasma and subsequent effect on complex biological pathways requires precision and a distinct understanding of how physiological redox chemistry is manipulated. Chemical modification of biomolecules such as carbohydrates, proteins, and lipids treated with cold plasma have been characterized, however, the context of how alterations of these molecules affect cell behavior or in vivo functionality has not been determined. Thus, this study examines the cytotoxic and mutagenic effects of plasma-treated molecules in vitro using CHO-K1 cells and in vivo in Galleria mellonella larvae. Specifically, albumin, glucose, cholesterol, and arachidonic acid were chosen as representative biomolecules, with established involvement in diverse bioprocesses including; cellular respiration, intracellular transport, cell signaling or membrane structure. Long- and short-term effects depended strongly on the molecule type and the treatment milieu indicating the impact of chemical and physical modifications on downstream biological pathways. Importantly, absence of short-term toxicity did not always correlate with absence of longer-term effects, indicating the need to comprehensively assess ongoing effects for diverse biological applications.

The antimicrobial and tissue healing efficacy of the atmospheric pressure cold plasma on grade III infected pressure ulcer: randomized controlled in vivo experiment.

To evaluate the antimicrobial efficacy and wound healing effect of atmospheric pressure cold plasma (APCP) on an infected pressure ulcer (IPUs) model that was created on rats. A total of 18 rats was divided into APCP, silver sulfadiazine (AgS) and control groups to have six rats in each group. A third-grade pressure ulcer model was developed on the back of each of the rats, and pressure ulcers were infected by inoculation of multidrug resistance (MDR) Pseudomonas aeruginosa. A portable dielectric barrier discharge device was used to generate cold air plasma. APCP, AgS and saline treatments were carried out once a day for 14days. The effectiveness of the treatment was evaluated on days 5, 10 and 15. Surface area, depth, pressure ulcer healing scale (PUSH) and microbiological examination were used for evaluation. The results of this study showed that APCP was superior over AgS application and irrigation with saline by means of the reduction in surface area and depth of ulcers. Furthermore, PUSH score in plasma group was lower than other groups and histopathological examination showed a higher epithelization in APCP group. The average reductions of MDR P. aeruginosa for APCP, AgS and control groups were determined as 5·64±1·87, 1·91±0·90 and 1·22±0·88 log10 CFU per gram tissue, respectively. Atmospheric pressure cold plasma healed IPUs better than AgS. Portable cold plasma devices could be a potential novel treatment modality for the patients who have IPUs.

Impact of Short Time Atmospheric Plasma Treatment on Onion Seeds

The paper presents the results of an experiment on the effect of cold plasma (He + O2 and He + Air) generated in a radio frequency cold atmospheric plasma jet on the process of germination of onion cv. Wolska (Allium cepa L.) seeds. In order to determine the impact of the gas flow on the seed surface, CFD simulations and Schlieren imaging were performed and surface characteristics were studied using a digital microscope. Plasma treatment of the seeds was carried out four times (2, 5, 10 and 15 s) with one control group. Pre-sowing plasma stimulation of seeds improved the germination capacity and germination energy for all tested groups in comparison to the control. The best germination capacity and energy were obtained for seeds stimulated with 10 s of plasma treatment. Analysis of the data showed a statistically significant impact of plasma treatment on the onion seed’s germination parameters. Plasma treatment did not induce significant changes on the seed surface, as microscope images showed but length of all plasma-treated seedlings increased in comparison to control.

Effect of Radio Frequency Low Pressure Cold Plasma on Total Phenol, Antioxidant Activity and Colour Degradation Kinetics of Red Chilli Pepper Powder

The study was aimed to analyse the effect of low pressure cold plasma treatment [operated at 60.8 kPa on the quality parameters of red chilli pepper powder (RCPP)]. The experiments were conducted at two radio frequency power levels (60 W, 120 W) over a time range from 0 to 10 min. Total phenols, antioxidant activity, colour, and moisture content were determined. Results showed that radio frequency operating power and treatment time had significant negative effects (p < 0.05) on the quality parameters analysed. Cold plasma treatment reduced the redness, total phenol content, moisture content, and increased the antioxidant activity of the RCPP. Changes in the quality of the treated samples, especially the colour degradation were significant after 4 min of treatment. Degradation kinetics was determined for parameters studied to ascertain their order of reaction during cold plasma treatment. The order of reaction was decided from best fit models with the highest R2, minimum bias, and error sum of squares. Total phenol followed a zero-order, whereas antioxidant activity and colour followed first-order reactions. The study explored the possibilities and impact of using cold plasma for powdered food materials.

Comparative morphological assessment of the damaging effects of cold plasma and radio wave energy on the mucous membrane of the lip in the experiment

Experimental animals removed a portion of the mucous membrane of the inner surface of the lip with a Surgitron radio knife (group 1) and an electrode of the Coblator II cold plasma apparatus (observation group 2). Tissue was taken from the edge of the surgical wound as a trapezoidal flap containing mucous and submucous membranes immediately after the incision and 3 weeks after the surgery. Histological sections were prepared, which were stained with hematoxylin and eosin, as well as according to van Gieson. It was found that, both in cases of using a radio knife and a coblator along the edges and in the depth of the wound, coagulation tissue necrosis was observed, which was more evident in group 1 of observations. In addition, after the radio wave exposure, in the areas close to the defect, the epithelial lining was disrupted to one degree or another, which was not observed when using the coblator. After 3 weeks of the experiment, the stratified squamous non-keratinizing epithelium in both groups had a normal histological structure. At the same time, when using the coblator, the lamina propria of the mucous membrane was completely restored, and in cases with the use of a radio knife, sclerotic processes with the formation of scar tissue took place in the lamina propria of the mucous membrane in some areas. The use of a coblator should be recognized as a more gentle method, since a comparative analysis of histological changes immediately after the incision showed a more intense damaging effect of the radio knife on the surrounding tissues, which in later stages was accompanied by incomplete regeneration (substitution) of the lip mucosa.

Effects of cold plasma on avocado pulp (PerseaamericanaMill.): Chemical characteristics and bioactive compounds

The effects of cold plasma on the enzymatic activity, color, bioactive compounds, and antioxidant activity of avocado pulp with lime extract (PL) and without extract (PW) were studied. The experimental conditions applied varied with regard to time (10, 20, and 30 min) and gas flow (10, 20, and 30 ml). The gas flow combination of 20 ml/20 min applied in PL was efficient for reducing POD and PPO activities and browning index as well as for color maintenance. Cold plasma increased the phenolic and carotenoid levels in PW in T1 and T2 (gas flow 10 ml/10–30 min) and in PL in T3 and T8 (gas flow 30 ml/10 min and 20 ml/30 min), which contributed to the improvement in antioxidant activity. The phenolic showed a strong correlation with ORAC-H in PL (0.85) and PW (0.75). Myristic and palmitic acid were reduced after applying cold plasma, however, oleic, linoleic, and linolenic increased the content. It is concluded that the synergistic effect of lime extract in avocado pulp with cold plasma technology is efficient at maintaining the quality characteristics and improving the bioactive content. Practical applications Cold plasma processing is an alternative method of effective maintenance for enzyme control, and it also shows promising results in the conservation of chemical quality and in increasing the levels of bioactive compounds and increasing the antioxidant capacity in fruit products, such as avocado pulp. Avocado has gained prominence in the market due to knowledge of its nutritional characteristics; however, its commercialization is hampered mainly by a high concentration of enzymes that cause enzymatic browning, such as polyphenol oxidase and peroxidase, which favor the appearance of degradation reactions, compromising the quality of the fruit. Available information on the effect of this conservation technology on this type of matrix has not been found, and this is one of the first studies to address the effect of cold plasma processing on avocado pulp, providing information for the food industry.

Argon and nitrogen cold plasma effects on wheat germ lipolytic enzymes: Comparison to thermal treatment

The effects of argon and nitrogen cold plasma treatments on the lipolytic enzymes activity in wheat germ were investigated. Using argon as plasma gas, the residual activity of lipase and lipoxygenase decreased to 42.50% and 87.72%, respectively after 30 min. Switching plasma input gas to nitrogen, the residual activities of lipase and lipoxygenase after the same time of atmospheric cold plasma (ACP) treatment were 77.50% and 92.52%, respectively. The antioxidant potential and phenolic compounds show no significant difference during ACP duration. However, the remaining activities of lipase and lipoxygenase after 30 min steam autoclaving were 6.25% and 18.60%, respectively. Also, the antioxidant activity and total phenolic content reduced by 14.70% and 30.80%, respectively. In brief, the ACP treatment efficiency was function of the input gas and the treatment time. The presented results about the input gas impacts would be useful in industrial development of ACP application for wheat germ stabilization.

Effect of cold plasma and elicitors on bioactive contents, antioxidant activity and cytotoxicity of Thai rat-tailed radish microgreens.

Raphanus sativus var. caudatus or Thai rat-tailed radish (RTR) contains glucosinolates and isothiocyanates with chemopreventive effects; however, only mature plants have been investigated to date. Thus, the present study aimed to determine isothiocyanates, phenolic compounds and flavonoid compounds, antioxidant activity, cytotoxicity, and antiproliferative activity of RTR microgreens grown from seeds treated with cold plasma (21 kV for 5 min), organic elicitor (160 mmol L-1 NaCl, 10 mmol L-1 CaCl2 or 176 mmol L-1 sucrose) or both in combination. Seeds were germinated on vermiculite and sprayed with deionized water or elicitor for 7 days before harvest. Cold plasma had insignificant effect on growth, whereas NaCl and CaCl2 increased fresh weight. Plasma with CaCl2 led to the highest total isothiocyanate (ITC) content [1.99 g kg-1 dry weight (DW)] in RTR microgreens containing raphasatin as the only ITC detected. Plasma treatment gave the highest total phenolic content (7.56 mg gallic acid equivalents g-1 DW), antioxidant activity from a 2,2-diphenyl-1-picrylhydrazyl assay (7.70 mg trolox equivalents g-1 DW) and ferric reducing antioxidant power assay (21.72 mg Fe2+ g-1 DW). Microgreen extracts from plasma showed an IC50 value of 29.28 and 13.83 μg mL-1 towards MCF-7 and HepG2, respectively, with inhibitory properties on matrix metalloproteinase (MMP)-2 and MMP-9 proteins. Plasma enhanced Bax and Caspase-3 gene expression but reduced Bcl-2 and MMP-9 expression, indicating activation of apoptosis. Cold plasma shows promise as an innovative tool to enhance bioactive compounds with chemopreventive benefits in microgreens. © 2020 Society of Chemical Industry.

Effect of Cold Plasma on Quality Retention of Fresh-Cut Produce

In recent years, the consumption of the fresh-cut products has been increased due to the consumers’ lifestyle and awareness. However, maintaining the quality and nutritional value of these products during storage is being difficult in comparison to whole fruits and vegetables. In actual, the procedures used in the fresh-cut industry may intensify the deterioration caused by physical damage by minimal processing. Commonly, the quality degradation, discolouration, loss of moisture, loss of firmness, microbial load increase, and loss of nutrients and flavor occur in the fresh-cut product after minimal processing. To maintain the quality and increase the shelf-life of the fresh-cut product, it is necessary to use various techniques, including physical, chemical, and nondestructive processes. In this review, first, an introduction to minimal processing and its effect on fresh-cut product quality was expressed, and then, the methods used to maintain fresh-cut product quality after minimal processing were reviewed. Finally, the effect of cold plasma on the qualitative characteristics in some fresh-cut products was investigated. The review showed that cold plasma treatments can significantly inhibit microorganisms and extend the shelf-life of fresh-cut products. In addition, no or minimal impacts were observed on physicochemical and organoleptic quality attributes of the treated fresh-cut products. Therefore, the use of cold plasma is promising for the fresh-cut industry.

Effect of Cold Plasma on Meat Cholesterol and Lipid Oxidation.

Cold atmospheric plasma (CAP) is a novel non-thermal technology with potential applications in inactivating microorganisms in food products. However, its impact on food quality is not yet fully understood. The aim of this research is to study the impact of in-package plasma technology on the stability of cholesterol and total lipid in four different types of meat (beef, pork, lamb and chicken breast). Additionally, any changes in the primary or secondary lipid oxidation, which is undesirable from a health perspective, is investigated. CAP was not found to have any impact on the cholesterol or lipid content. However, higher peroxide and thiobarbituric acid reactive substances (TBARS) values were found for the treated samples, indicating that plasma can induce the acceleration of primary and secondary lipid oxidation. Finally, color was not affected by the treatment supporting the suitability of the technology for meat products.

Physical Plasma-Treated Skin Cancer Cells Amplify Tumor Cytotoxicity of Human Natural Killer (NK) Cells.

Simple SummaryNatural killer (NK)-cells are known to have antitumor potential. Cold physical plasma generates ROS exogenously to be utilized as a novel anticancer agent, especially in skin cancer. However, it is unknown whether plasma-treated skin cancer cells promote or inhibit NK-cell-mediated toxicity. To this end, we analyzed NK-cell-activating receptors on plasma-treated skin cancer cells and demonstrated an enhanced NK-cell activity augmenting tumor cell death upon plasma treatment.Skin cancers have the highest prevalence of all human cancers, with the most lethal forms being squamous cell carcinoma and malignant melanoma. Besides the conventional local treatment approaches like surgery and radiotherapy, cold physical plasmas are emerging anticancer tools. Plasma technology is used as a therapeutic agent by generating reactive oxygen species (ROS). Evidence shows that inflammation and adaptive immunity are involved in cancer-reducing effects of plasma treatment, but the role of innate immune cells is still unclear. Natural killer (NK)-cells interact with target cells via activating and inhibiting surface receptors and kill in case of dominating activating signals. In this study, we investigated the effect of cold physical plasma (kINPen) on two skin cancer cell lines (A375 and A431), with non-malignant HaCaT keratinocytes as control, and identified a plasma treatment time-dependent toxicity that was more pronounced in the cancer cells. Plasma treatment also modulated the expression of activating and inhibiting receptors more profoundly in skin cancer cells compared to HaCaT cells, leading to significantly higher NK-cell killing rates in the tumor cells. Together with increased pro-inflammatory mediators such as IL-6 and IL-8, we conclude that plasma treatment spurs stress responses in skin cancer cells, eventually augmenting NK-cell activity.

The Effect of Plasma Treatment on the Speed of Healing of Wounds Similar to battle wounds

Cold plasma has been successfully applied in several fields of medicine. Previous studies have provided evidence that plasma supports the healing of wounds. This work was done to study the effect of cold plasma on the speed of wounds recovery for wounds Similar to battle wounds implemented on rats. The rats were divided into four groups; the control group was injured and left untreated, in order to compare it with the groups that were treated. And the second group was treated with penicillin only Six hours after applying the wound. And the third group was treated with an argon plasma jet immediately after the wound is applied and polluted with dust. The fourth group was treated with penicillin and plasma, the plasma was used immediately, but the penicillin was used after six hours. The wound was 1 cm long and 0.5 mm deep. The rats were treated by plasm jet for three days 15 minutes per day, and the penicillin was used daily once according to the protocol. The wounds were photographed as soon as they were performed; it was visually monitored, and documented with photos after three days, seven days, and fourteen days later. It was found that wounds treated with plasma and penicillin are the best case of treatment with penicillin alone or with plasma alone, and treatment with plasma alone is better than treatment with penicillin alone. Where the wound size was became smaller and fully healed. That was by comparison with the control group that was left untreated. From this we can conclude that plasma is a possible way to speed of healing of wounds similar to battle wounds.

Cold Plasma Treatment Accelerates Regeneration of the Skin after Mechanical Damage

The results of an experimental study of the cold plasma effect on skin regeneration after mechanical damage of various types are presented. It has been shown that the use of cold plasma accelerates wound healing and significantly reduces inflammatory processes.

Effect of atmospheric cold plasma on the functional properties of whole wheat (Triticum aestivum L.) grain and wheat flour

Atmospheric cold plasma (ACP) has emerged as a novel processing technology, with demonstrated efficiencies in microbial inactivation. However, studies on the effects of ACP and potential to modify the functional properties of foods are sparse. The objective of this study is to determine the effect of ACP on physico-chemical and functional properties of wheat flour. In this study, both whole wheat grains and wheat flour were subjected to a dielectric barrier discharge (DBD) contained plasma reactor for a range of treatment times (5–30 min) at 80 kV. Plasma treatment increased the flour hydration properties of wheat flour. Rapid visco-analyser results showed an increase in pasting and the final viscosities of wheat flour. The decrease in both endothermic enthalpies and crystallinity was attributed to the depolymerization of starch and plasma-induced changes. Overall DBD-ACP treatment can be tailored to develop a plasma process with potential to improve functionality of wheat flour.

Effect of high voltage atmospheric cold plasma on extraction of fenugreek galactomannan and its physicochemical properties

Fenugreek is a good source of galactomannan, however, conventional methods for its extraction are generally time-consuming and have relatively low recovery rates. In this study, we applied high voltage atmospheric cold plasma (HVACP) as a pretreatment and investigated its effects on galactomannan extraction from dry fenugreek seeds and soaked seeds in NaCl solution, as well as its physicochemical properties. Results showed that HVACP treatment with air at 80 kV for 30 min caused apparent structural disruption on fenugreek seed surface and decreased the pH of extracting solution, resulting in increased galactomannan extraction yields, by 122% from soaked seeds and 67% from dry seeds. Galactomannan treated with HVACP had higher water-binding capacity, swelling index and viscosity, as well as lower melting enthalpy. HVACP treatment also altered the surface morphology of galactomannan due to plasma etching, but no significant changes in its molecular and crystalline structures were observed. The findings of this study prove that HVACP can be a green approach, in terms of reduced chemical use, to effectively enhance the extraction efficiency of fenugreek galactomannan and modify its functional properties, hence facilitate more diverse applications in both food and polymer industries.

Enhancement of polyphenolic content extraction rate with maximal antioxidant activity from green tea leaves by cold plasma.

A dielectric barrier discharge (DBD) atmospheric cold plasma was evaluated as a tool to increase the extraction rate of total phenolic content (TPC) and antioxidant activity from green tea leaves. The effects of nitrogen DBD cold plasma on changes of color and surface morphology were investigated. Optimum conditions of cold plasma treatment (treatment time and generation power) were obtained by response surface methodology. After the nitrogen DBD cold plasma at 15 W of the generation power for 15min, the TPC and antioxidant activity of green tea increased by 41.14% and 41.06%, respectively. The catechin also increased by 103.12%. The scanning electron microscopy results showed cell ablation and ruptures of the green tea leaf surface after nitrogen DBD cold plasma treatment. PRACTICAL APPLICATION: The developed DBD cold plasma source fed by nitrogen gas can be a suitable procedure for green and useful extraction of phenolic compounds from natural sources in the food industries.

Cold plasma jet with dielectric barrier configuration: Investigating its effect on the cell membrane of E. coli and S. cerevisiae and its impact on the quality of chokeberry juice

Here, we investigated the effects of cold plasma (CP), a nonthermal processing technology, on Escherichia coli and Saccharomyces cerevisiae inactivation and the quality of chokeberry juice (CJ). A CP jet with a dielectric barrier configuration was used to process the CJ, and the inactivation of E. coli and S. cerevisiae was evaluated using microscopy and propidium iodide staining. Microbial inactivation increased with treatment time and decreased with sample volume, and E. coli was inactivated to a greater extent than S. cerevisiae. The CP sterilization effect is possibly due to CP-generated active particles, such as reactive oxygen species, which attack microbial cell membranes and intracellular components leading to cell rupture. Relative to control juice, CP did not affect titratable acid, soluble reducing sugar, and soluble solid percentage values. Moreover, CP was superior to thermal treatment (90 °C for 15 s) given the improved anthocyanin, phenol, and vitamin C content, reduced color change, and enhanced antioxidant capacity of the processed CJ. Therefore, CP may be a promising method for CJ juice processing.

Investigation of decontamination effect of argon cold plasma on physicochemical and sensory properties of almond slices

Cold plasma is a novel technology for surface decontamination. Almond slices can be contaminated with different microorganisms during their production. In the current research, the atmospheric argon plasma treatment (5, 10, 15, and 20 min) was used to decontamination of almond slices surface. Microbial load, Color, peroxide value, hardness, and sensory properties of slices was comprised with untreated samples (control). Descriptive sensory evaluation about color, flavor, crispiness, crunchiness, and hardness of almond slices were performed. According to the results of the microbial tests, Total count, molds and yeasts, and Staphylococcus aureus of almond surface decreased about 2.95 log cfu/g, 1.81 log cfu/g, and 2.72 log cfu/g after 20 min of plasma treatment, respectively, provided that microbial reduction increased more by increasing the treatment time. Coupled with the color evaluation, peroxide value and sensory attributes didn't change during plasma treatment. Having said that, the hardness of slices was changed by increasing treatment time. Furthermore, Principal Component Analysis and cluster analysis were performed for sensory evaluation. In light of the consumer's point of view, firstly 10 min and secondly 15 min plasma treatment can be more desirable.

Effects of cold plasma on wheat grain microbiome and antimicrobial efficacy against challenge pathogens and their resistance

The safety and quality of cereal grain supplies are adversely impacted by microbiological contamination, with novel interventions required to maximise whole grains safety and stability. The microbiological contaminants of wheat grains and the efficacy of Atmospheric Cold Plasma (ACP) for potential to control these risks were investigated. The evaluations were performed using a contained reactor dielectric barrier discharge (DBD) system; samples were treated for 0–20 min using direct and indirect plasma exposure. Amplicon-based metagenomic analysis using bacterial 16S rRNA gene and fungal 18S rRNA gene with internal transcribed spacer (ITS) region was performed to characterize the change in microbial community composition in response to ACP treatment. The antimicrobial efficacy of ACP against a range of bacterial and fungal contaminants of wheat, was assessed to include individual isolates from grains as challenge pathogens. ACP influenced wheat microbiome composition, with a higher microbial diversity as well as abundance found on the untreated control grain samples. Culture and genomic approaches revealed different trends for mycoflora detection and control. A challenge study demonstrated that using direct mode of plasma exposure with 20 min of treatment significantly reduced the concentration of all pathogens. Overall, reduction levels for B. atrophaeus vegetative cells were higher than for all fungal species tested, whereas B. atrophaeus spores were the most resistant to ACP among all microorganisms tested. Of note, repeating sub-lethal plasma treatment did not induce resistance to ACP in either B. atrophaeus or A. flavus spores. ACP process control could be tailored to address diverse microbiological risks for grain stability and safety.