Effect Of Cold Atmospheric Plasma Research Articles

Increasing the efficiency of cumin essential oil extraction using cold plasma pretreatments.

Cumin (Cuminum cyminum L.) is one of the most important medicinal plants, and its essential oil (EO) varies between 2.5% to 5% depending on differences in climate. The extraction method plays a significant role in the market price of EOs. In this study, the effect of atmospheric cold plasma (ACP) pretreatments (using air and argon (Ar) gases) for different times on the EO yield and on the quality, color, surface morphology, and wettability of cumin seeds were studied. The scanning electron microscope analysis results revealed that the formation of fissures and cracks caused by ACP pretreatments was directly related to increasing the efficiency of EO extraction. Comparing the two gas treatments, the highest total color changes ΔE were related to the Ar and the lowest to the air treatment, and the highest amount of browning index was related to the Ar ACP pretreatment. In general, the ACP pretreatments improved the extraction efficiency compared with the control, so that the highest increase was observed in the Ar ACP pretreatment at the rate of 44%. Ar ACP pretreatments were observed to have a higher extraction efficiency than air ACP did. In the Ar ACP-treated samples, cumin aldehyde, as the most important component of EO, was increased compared with the control (47.9-56.4%). The data obtained in this study showed that ACP pretreatment of cumin seeds could increase EO extraction efficacy. Thus, ACP could be a promising technique to enhance the cumin seed EO extraction. © 2024 Society of Chemical Industry.

Argon cold atmospheric plasma eradicates pathogens in vitro that are commonly associated with canine bacterial keratitis.

To investigate the antimicrobial effect of cold atmospheric plasma (CAP) on pathogens associated with canine bacterial keratitis. Pseudomonas aeruginosa, Staphylococcus pseudintermedius, and Streptococcus canis strains, which were obtained from dogs with infectious keratitis, were subjected to testing. For each species, four isolates and a reference strain were cultivated on Columbia sheep blood agar and treated with the kiNPen Vet® plasma pen from Neoplas GmbH, Greifswald, Germany. Various continuous treatment durations (0.5, 2, and 5 min) were applied, along with a 0.5-min treatment repeated four times at short intervals. These treatments were conducted at distances of 3 and 18 mm between the agar surface and the pen. CAP treatment reduced bacterial growth in all three species. The most effective treatment duration was 5 min at 3 mm distance, resulting in inhibition zones ranging from 19 to 22 mm for P. aeruginosa, 26-45 mm for S. pseudintermedius and an overall reduction of bacterial growth for Str. canis. Inhibition zones were smaller with decreasing treatment duration and larger distance. Treatment times of 30 s repeated four times and 2 min showed comparable results. Treatment with argon alone did not lead to visible reduction of bacterial growth. Argon cold atmospheric plasma demonstrated a potent in vitro antimicrobial effect on P. aeruginosa, S. pseudintermedius and Str. canis strains with the latter showing the highest sensitivity.

Cold Atmospheric Helium Plasma in the Post-COVID-19 Era: A Promising Tool for the Disinfection of Silicone Endotracheal Prostheses.

Despite the excellent properties of silicone endotracheal prostheses, their main limitation is the formation of a polymicrobial biofilm on their surfaces. It can cause local inflammation, interfering with the local healing process and leading to further complications in the clinical scenario. The present study evaluated the inhibitory effect of cold atmospheric plasma (CAP) on multispecies biofilms grown on the silicone protheses' surfaces. In addition to silicone characterization before and after CAP exposure, CAP cytotoxicity on immortalized human bronchial epithelium cell line (BEAS-2B) was evaluated. The aging time test reported that CAP could temporarily change the silicone surface wetting characteristics from hydrophilic (80.5°) to highly hydrophilic (<5°). ATR-FTIR showed no significant alterations in the silicone surficial chemical composition after CAP exposure for 5 min. A significant log reduction in viable cells in monospecies biofilms (log CFU/mL) of C. albicans, S. aureus, and P. aeruginosa (0.636, 0.738, and 1.445, respectively) was detected after CAP exposure. Multispecies biofilms exposed to CAP showed significant viability reduction for C. albicans and S. aureus (1.385 and 0.831, respectively). The protocol was not cytotoxic to BEAS-2B. CAP can be a simple and effective method to delay multispecies biofilm formation inside the endotracheal prosthesis.

Effect of cold atmospheric plasma on changing of biomolecular structures involved in apoptosis pathways of melanoma cancer.

Cold atmospheric plasma (CAP), is a technology based on non-thermal ionized gas that is used for cancer therapy in research. We evaluated the effect of CAP on malignant melanoma cancer cell line (B16) in comparison with normal cells (L929). The effect of CAP on the cytotoxicity of B16 and L929 cell lines was assayed by the MTT method and inverted microscopy. The induction of apoptosis in cells was evaluated using a fluorescence microscope. FTIR monitored the CAP effect in biomacromolecules changes in these cell lines. QPCR assayed gene expression of BAX, BCL-2, and Caspase-3 (CASP-3). The results of the MTT test showed CAP has a cytotoxic effect on the B16 cancer cell line more than L929 normal cells (p<0.0001). The results of invert and fluorescence microscopy showed CAP-induced apoptotic morphology on cancerous cells. FTIR spectroscopy indicated CAP changes biomacromolecules structure. Evaluation of gene expression showed CAP increased BAX and CASP-3 gene expression. Also, it decreased BCL-2 gene expression. Taken together, CAP may change biomacromolecule structures involved in apoptosis pathways, decrease proliferation and induce apoptosis in cancer cells.

Effect of Cold Atmospheric Plasma on Hyperglycemia and Immunity in the Spleen of STZ Diabetic Mice

Effect of Cold Atmospheric Plasma on Hyperglycemia and Immunity in the Spleen of STZ Diabetic Mice

Helium Cold Atmospheric Plasma Causes Morphological and Biochemical Alterations in Candida albicans Cells

(1) Background: Previous studies reported the promising inhibitory effect of cold atmospheric plasma (CAP) on Candida albicans. However, the exact mechanisms of CAP’s action on the fungal cell are still poorly understood. This study aims to elucidate the CAP effect on C. albicans cell wall, by evaluating the alterations on its structure and biochemical composition; (2) Methods: C. albicans cells treated with Helium-CAP were analyzed by atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR) in order to detect morphological, topographic and biochemical changes in the fungal cell wall. Cells treated with caspofungin were also analyzed for comparative purposes; (3) Results: Expressive morphological and topographic changes, such as increased roughness and shape modification, were observed in the cells after CAP exposure. The alterations detected were similar to those observed after the treatment with caspofungin. The main biochemical changes occurred in polysaccharides content, and an overall decrease in glucans and an increase in chitin synthesis were detected; (4) Conclusions: Helium-CAP caused morphological and topographic alterations in C. albicans cells and affected the cell wall polysaccharide content.

Inhibitory effects of cold atmospheric plasma on population growth of the carob moth, Ectomyelois ceratoniae (Lepidoptera: Pyralidae) in laboratory.

Potential sterilizing effects of the atmospheric cold plasma on the carob moth, Ectomyelois ceratoniae Zeller (Lepidoptera: Pyralidae) was studied under laboratory conditions by means of life history experimentation. The results showed that the population growth parameters of the carob moth decreased in all periods of 15 to 60 sec of plasma treatments applied on 1 -day-old eggs. Overall, 19.5% and 23.8% of reproduced eggs were fertile when the experimental males and females mated with normal moths in indirect treatments of 15 and 30 sec, respectively. The highest intrinsic rate of population increase, r, was in control (0.11 day-1) and the highest decrease in this parameter was in the 30 sec direct treatment (- 0.073 day-1). The results showed that cold plasma had an acceptable potential to sterilize the pest if plasma was applied at egg stage. This potential will be explored from the perspective of insect sterility technique and the genetical / physiological mechanisms involved should be studied in future.

Enhanced Antimicrobial Activity through Synergistic Effects of Cold Atmospheric Plasma and Plant Secondary Metabolites: Opportunities and Challenges.

The emergence of antibiotic resistant microorganisms possesses a great threat to human health and the environment. Considering the exponential increase in the spread of antibiotic resistant microorganisms, it would be prudent to consider the use of alternative antimicrobial agents or therapies. Only a sustainable, sustained, determined, and coordinated international effort will provide the solutions needed for the future. Plant secondary metabolites show bactericidal and bacteriostatic activity similar to that of conventional antibiotics. However, to effectively eliminate infection, secondary metabolites may need to be activated by heat treatment or combined with other therapies. Cold atmospheric plasma therapy is yet another novel approach that has proven antimicrobial effects. In this review, we explore the physiochemical mechanisms that may give rise to the improved antimicrobial activity of secondary metabolites when combined with cold atmospheric plasma therapy.

The Effectiveness of Cold Atmospheric Plasma (CAP) on Bacterial Reduction in Dental Implants: A Systematic Review.

The emergence of dental implants has revolutionized the management of tooth loss. However, the placement of clinical implants exposes them to complex oral environment and numerous microscopic entities, such as bacteria. Cold atmospheric plasma (CAP) is often used to treat the surfaces of dental implants, which alters morphological features and effectively reduces bacterial load. This systematic review aims to assess the existing literature on the bactericidal properties of CAP when used on various kinds of dental implant surfaces. An in-depth examination of MEDLINE/PubMed and EMBASE was performed to identify relevant studies, with the most recent search conducted in May 2023. Studies were selected based on their exploration of CAP's effects on dental implants compared to control groups, focusing on CAP's bactericidal efficacy. However, studies that lacked a control group or that failed to measure bactericidal effects were excluded. After applying the selection criteria, 15 studies were ultimately included in the systematic review. The collected data suggest that CAP can effectively reduce bacterial loads on dental implant surfaces, including pathogens like Streptococcus mitis and Staphylococcus aureus. Furthermore, CAP appears to combat biofilms and plaques that are key contributors to periimplantitis. CAP emerges as a promising treatment option, exhibiting significant bactericidal activity on dental implant surfaces. CAP can decrease the rates of bacterial biofilm and plaque formation, leading to improved outcomes for dental implant patients.

Effects of cold atmospheric plasma pre-treatment on maintaining the quality of ready-to-eat drunken red shrimp (Solenocera crassicornis) stored at chilled conditions

This present study investigated the effect of cold atmospheric plasma (CAP) pre-treatment on the quality of ready-to-eat drunken red shrimp (Solenocera crassicornis) during chilled storage. The shrimp were pre-treated with the CAP at 40 kV and 36 kH for 100 s in a plasma generating equipment before the drunken treatment and compared with an untreated control sample. The results showed that the CAP pre-treatment significantly inhibited the total viable count (TVC) values, total volatile basic nitrogen (TVB-N) content, and polyphenol oxidase (PPO) activity of the drunken shrimp compared to the control treatment. Furthermore, the CAP pre-treatment also significantly maintained the myofibrillar protein (MP) content, texture properties, and a more stable histological structure of muscle fibers compared to the control. High-throughput sequencing results confirmed that the CAP pre-treatment significantly reduced the diversity and abundance of several bacteria in the shrimp. Gas chromatography-ion mobility spectrometry (GC-IMS) analysis detected that the CAP pre-treatment effectively maintained the stability of volatile organic compounds (VOCs). These findings provide valuable theoretical support for the processing and storage of drunken shrimp.

Nanosecond pulsed cold atmospheric plasma jet suppresses proliferation and migration of human glioblastoma cells via apoptosis promotion and EMT inhibition

Glioblastoma (GBM) is one of the most aggressive and challenging cancers to treat. Despite extensive research on dozens of cancer cells, including GBM, the effect of cold atmospheric plasma (CAP) on the invasive migration of GBM cells has received limited attention, and the underlying mechanisms remain poorly understood. This study aims to investigate the potential molecular mechanism of ns-CAPJ in inhibiting the invasive migration of human GBM cells. The findings indicate that ns-CAPJ significantly reduces GBM cell invasion and migration, and induces apoptosis in GBM cells. Further mechanistic studies demonstrate a direct correlation between the suppression of the epithelial-mesenchymal transition (EMT) signaling pathway and ns-CAPJ’s inhibitory effect on GBM cell invasion and migration. Additionally, combined with the N-acetyl cysteine (NAC, a ROS inhibitor) assay, we found that the ROS stimulated by the ns-CAPJ plays an important role in suppressing the EMT process. This work is expected to provide new insight into understanding the molecular mechanisms of how ns-CAPJ inhibits the proliferation and migration of human GBM cells.

Cold atmospheric plasma fumigation suppresses postharvest apple Botrytis cinerea by triggering intracellular reactive oxygen species and mitochondrial calcium

Infection by Botrytis cinerea poses a great threat to the postharvest life of apple fruit. In this study, the effects of cold atmospheric plasma (CAP) fumigation on apple B. cinerea under different exposure times and intensities were investigated. The growth of B. cinerea in vitro and in vivo was significantly suppressed by the CAP fumigation at least 700 μL/L for 5 min. To reveal the possible mechanism of antifungal activity of CAP fumigation, the pathogen was exposed to 700 μL/L and 1000 μL/L for 5 min, respectively. The results indicated that the CAP-treated spores of the pathogen underwent shrinkage, cell membrane collapse and cytoplasmic vacuolation. The results obtained from the fluorescent probe assay and flow cytometry indicated that CAP caused the accumulation of reactive oxygen species (ROS), the elevation of mitochondrial and intracellular Ca2+ levels, and the decrease in mitochondrial membrane potential of the pathogen. Investigation on statues of cell life showed that typical hallmarks of apoptosis in the CAP-treated B. cinerea spores occurred, as indicted by a large degree of increased phosphatidylserine externalization, dysfunction of membrane permeability, DNA fragmentation, distortion of morphology, chromatin condensation, and metacaspase activation observed in B. cinerea spores after CAP fumigation. Overall, CAP fumigation triggered a metacaspase-dependent apoptosis of B. cinerea spores mediated by intracellular ROS burst and Ca2+ elevation via mitochondrial dysfunction and disruption, and therefore reduced the pathogenicity of B. cinerea and suppressed postharvest Botrytis rot of apple fruit. These results would provide an insight into the underlying mechanism of CAP fumigation acting on the pathogen. The CAP fumigation makes much convenient application of CAP in storage environment to deactivate microorganism.

Positive effects of cold atmospheric plasma on pH in wounds: a pilot study.

Cold atmospheric plasma (CAP) is a promising new option for the treatment of hard-to-heal (chronic) wounds. The aim of this study was to observe the effect of CAP on wound pH, as a correlation between the pH of a wound and its healing tendency has been established in the literature. Patients with hard-to-heal wounds were treated with CAP in addition to standard treatment. Treatment was performed with the aid of a small, mobile plasma device, which was used for one minute at a time during dressing changes. The pH value, wound size, and other parameters, such as exudate and signs of infection, were recorded for each treatment. A total of 10 patients took part in the study. During the observation period, there was a significant reduction in pH from a markedly alkaline pH of 9.6 to a neutral pH of 7. This was accompanied by a marked reduction in wound size by an average of 76% with seven applications of CAP within 28 days. The evaluation of tissue granulation, exudate and signs of infection showed a positive trend. The number of patients in the present study is not sufficient to prove the relationship between the pH value of the wound and the treatment with CAP. However, there are clear indications that the positive effects of CAP on wound healing, which are recognised in several publications, are also due to its influence on wound pH value.

Effect of Atmospheric Cold Plasma on the Aroma of Pineapple Juice: Improving Fresh and Fruity Notes and Reducing Undesired Pungent and Sulfurous Aromas

Pineapple aroma is characterized by several esters, which confers its fresh and fruity aroma. However, high concentrations of methyl hexanoate and thioesters bring an undesired pungently sweet aroma and sulfurous notes to pineapple juice. This study investigates the chemical effects of cold plasma on the aroma compounds and descriptors of pineapple juice, evaluating the effects of plasma on its esters and thioesters. Dielectric barrier discharge plasma was applied to pineapple juice, varying the excitation frequency (50 to 1000 Hz) and processing time (10 to 20 min) at constant voltage (20 kV). Plasma treatment induced successive demethylation of esters and the conversion of methyl esters into ethyl esters. Thioesters showed to be more stable under plasma treatment. Proper setting of plasma operating conditions enabled an improvement in the fresh and fruity descriptors of pineapple juice, a reduction of its undesired pungently sweet aroma, but an increase in the influence of sulfurous descriptors. Plasma treatment at 50 Hz reduced the undesired aromas of pineapple while maintaining its fresh and fruity descriptors.

Coconut milk treated by atmospheric cold plasma: Effect on quality and stability

Commercial sterilization plays an important role in extending the shelf-life of coconut milk. However, thermal sterilization affects the quality of coconut milk. This study was initiated to evaluate the effects of atmospheric cold plasma (ACP) treatment on some important quality parameters of coconut milk. ACP treatment had a slight effect on physicochemical characteristics and nutritional ingredients while it obviously reduced the colony count. Furthermore, ACP treatment obviously promoted the formation of lactone, an indispensable volatile substance in coconut milk. Insufficient or moderate ACP treatment had subtle effect on the sensory quality. Notably, moderate ACP treatment reduced the droplet size from 28.0 μm to 18.6 μm, and improved the stability during storage and centrifugation, especially at 60 kV 60 s. Overall, sterilization of coconut milk by ACP at 60 kV 60 s was the most ideal. This study can provide theoretical guidance for the application of ACP in liquid food.

Effect of cold atmospheric plasma induced electric field on aquaporin-5 structure and ROS transport

Cold atmospheric plasma (CAP) treatment has been believed to be a promising anticancer technology. Aquaporins (AQPs) are inferred as a main but unverified route of ROSs transport into cancer cells. Molecular dynamics simulations were carried out to assess the effect of CAP-induced electric field on the AQP5-biolayer combination, the AQP5 structure, and the ROS distribution. Results show that the electric field can weaken the AQP5-biolayer combination, and narrow the radius of AQP5 water pores by changing the distance of key residues. From the perspective of ROS, the electric field sharply changes the free energy profiles of polarized ROSs but hardly affects the distribution of hydrophilic ROSs. This work provides a microscopic perspective of the CAP anticancer mechanism and puts forward the electric field as a new factor in CAP-related research.

Anticancer Effect of Cold Atmospheric Plasma in Syngeneic Mouse Models of Melanoma and Colon Cancer.

Cold atmospheric plasma (CAP) may have applications in treating various types of malignant tumors. This study assessed the anticancer effects of CAP using melanoma and colon cancer cell lines. CAP treatment significantly reduced the in vitro viability of melanoma and colon cancer cell lines and had a negligible effect on the viability of normal human melanocytes. Additionally, CAP and epidermal growth factor receptor (EGFR) inhibitor had an additive anticancer effect in a CAP-resistant melanoma cell line. Reactive oxygen and nitrogen species known to be generated by CAP enhanced the anticancer effects of CAP and EGFR inhibitors. The in vivo anticancer activities of CAP were evaluated by testing its effects against syngeneic tumors induced in mice by melanoma and colon cancer cells. CAP treatment reduced tumor volume and weight in both cancer models, with the extent of tumor reduction dependent on the duration and number of CAP treatments. Histologic examination also revealed the tumoricidal effects of CAP in both tumor models. In conclusion, CAP inhibits the growth of mouse melanoma and colon cancer cell lines in vitro and shows tumoricidal effects against mouse models of melanoma and colon cancer in vivo.

The effect ofcold atmospheric plasma (NO) alone and incombination with NPH insulin onthe full-thickness excisional wound healing inadiabetic rat model.

This study was planned toinvestigate analternative treatment modality indiabetic wound healing. Inthis experimental study, the efficacy ofboth cold atmospheric plasma/nitric oxide (NO) and NPH insulin ointment, recently known tohave beneficial effects onwound healing, was investigated indiabetic wound healing. Twenty-four (24) diabetic rats were divided into four groups DC, DI, DNO and DINO (diabetic control, diabetic insulin, diabetic nitric oxide, diabetic insulin+ nitric oxide groups). Notreatment was applied tothe DC group, NPH insulin was applied tothe DI group, CAP/NO was applied tothe DNO group, and CAP/NO+ NPH insulin was applied tothe DINO group once daily for 14days. The wound area reduction and the wound contraction rate were calculated onthe basis ofthe tissue sections taken, and histopathological and genetic analyses were carried out. Compared tothe control group, exogenous NO gas was found tobe apotent antibacterial agent inthe diabetic wound healing, causing areduction inthe wound area (P=0.034), anincreased contraction rate (P=0.021), epithelialisation (P=0.02), collagen organisation (P=0.006) and areduction inthe number ofinflammatory cells (P=0.002). Asignificant increase inthe expression ofIL-8 mRNA was observed (P=0.026). Itwas concluded that NPH insulin alone contributes towound healing, but itis not necessary touse ittogether with exogenous NO gas.

Impact of cold plasma treatment on nutritional, antinutritional, functional, thermal, rheological, and structural properties of pearl millet flour

AbstractThis study was planned to investigate the effect of atmospheric cold plasma (CP) treatment at different power levels (20–30 kV) for 10–20 min on physicochemical, technofunctional, and intermolecular changes of pearl millet flour (PMF). It was observed that exposure to plasma significantly modified the sample's proximate, antinutritional, functional, thermal, rheological, and morphological properties. A concomitant (p &lt; 0.05) decreases in antinutritional factors (tannin and phytic acid) was noticed in CP‐treated PMF compared to the control sample. Maximum reduction in tannin and phytic acid was observed at 30 kV for 20 min‐treated PMF. However, scanning electron microscopy revealed significant changes in flour starch granular structure, while decreases in relative crystallinity were also observed in CP‐treated samples from 23.45% to 19.31%. In addition, an increase in water absorption capacity (1.32–1.62 g/g), oil absorption capacity (1.11–1.31 g/g), emulsifying capacity (EC; 86.58%–91.25%) and foaming capacity (FC; 10.67–12.84%), as well as a decrease in pH (7.83–6.97) were found at 30 kV for 20 min. Apart from this, high intensity CP‐treated samples showed shear thinning behavior. At the same time, the power–law model was more appropriate for determine the flow behavior index (n) and consistency coefficient (k). On the other hand, CP‐treated samples exhibit higher storage modulus values (G′), indicating an elastic response. Based on the observations, the 30 kV‐20 min‐treated sample could be used for product formulation, contains lower antinutritional factors and retaining the nutritional components and functional properties.Practical applicationsThis work has identified that exposure to cold plasma improved the physicochemical, rheological, thermal, and functional properties of pearl millet flour with considerably reducing its antinutritional content, which can be helpful for various food industries. This possibly will encourage its application in the development of various food products, (like cookies, biscuits, bread, beverages, etc.) chiefly as a functional food ingredient.

Effects of Cold Atmospheric Plasma on Infectious Diabetic Wound Healing in Rat Models

Objectives: Patients with diabetes often suffer from chronic wounds which can occur due to the impairment of wound healing in these patients. Scientists have been trying to address this issue by using wide spectrum of antibiotics and drugs. However, overusing antibiotics in recent years has led to antibiotic resistant crisis; therefore, there is an urgent need to develop new approaches in order for controlling microbial infections in diabetic patients. This study aimed to determine if cold plasma was effective in wound healing in the infectious diabetic conditions. Material and Methods: In this experimental study, 40 adult male rats with diabetes infected with Staphylococcus aureus were included. The animals were randomly divided into two groups of 20 rats and four sub-groups (i.e., day 3rd, day 7th, day 14th, and day 21st). The rats in the treatment group were exposed to helium plasma irradiated for 3 minutes per day for 21 days. Wound healing in the samples was evaluated using five healing indexes including epithelium formation, Inflammatory cells, new vascularization, fibroblast, and collagen formation. Results: A significant difference (P&lt;0.05) was found between the indexes in the plasma radiation group compared to the control group. The results showed that the speed of wound healing in the group treated with cold helium gas plasma was higher than that in the control group. Collagen formation was always completed faster in the helium plasma group, indicating the positive effects of helium plasma on infected diabetic wounds. Conclusions: Helium plasma was remarkable effective in healing wound and controlling infections in diabetic rats.