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This study investigated the microbial decontamination of saffron using the low‐pressure cold plasma (LPCP) technology. Therefore, other quality characteristics of saffron that create the color, taste, and aroma have also been studied. The highest microbial log reduction was observed at 110 W for 30 min. Total viable count (TVC), coliforms, molds, and yeasts log reduction were equal to 3.52, 4.62, 2.38, and 4.12 log CFU (colony‐forming units)/g, respectively. The lowest decimal reduction times (D‐values) were observed at 110 W, which were 9.01, 3.29, 4.17, and 8.93 min for TVC, coliforms, molds, and yeasts. LPCP treatment caused a significant increase in the product's color parameters (L*, a*, b*, ΔE, chroma, and hue angle). The results indicated that the LPCP darkened the treated stigma's color. Also, it reduced picrocrocin, safranal, and crocin in treated samples compared to the untreated control sample (p <.05). However, after examining these metabolites and comparing them with saffron‐related ISO standards, all treated and control samples were good. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine mechanical and physical properties of starch/chitosan composite film exposed to low‐pressure air and argon plasma at 600 mTorr for different duration (4, 8 and 12 min) and evaluate the shelf life of the chicken breast fillet packaged with plasma‐treated films. The mechanical properties of the composite films were improved significantly. It is shown that argon plasma is more efficient in improving the tensile strength of the films and increased it from 10.59 to 22.09 Mpa after 12 min of process due to the formation of a stable cross‐linked network on the surface of the polymer, although film's stretchability, modified in air plasma, was significantly more. Solubility and hydrophilicity of the films were increased; however, no significant change in the water vapor transmission rate was observed. Oxygen permeability of films improved after both plasma treatment. Total viable count and oxidative (TBA) changes of fillets were analyzed during shelf life. The results showed that Cold plasma treatment could not prolong the shelf life of the fillets through plasma‐treated films. [ABSTRACT FROM AUTHOR]

In this research, the polypropylene (PP) sheets used for automotive bumper surface were treated using two methods: air atmospheric gliding arc plasma and flame modifications. Atomic force microscopy was applied to study the morphology of surfaces before and after treatment processes. While calculating the surface free energy (SFE), contact angle of the surfaces was measured, and the chemical composition of the PP surface was analyzed using X‐ray photoelectron spectroscopy. Surface modifications by gliding arc plasma increased the ratio of the oxygen and nitrogen atoms on the surface by 100%, indicating that polar chemical functionalities form on the surface. The surface morphology was highly affected by gliding arc plasma treatments, which triggered an impact on roughness and etching. It was also found that the SFE was drastically increased by certain modifications. Noticeable improvement was also observed in wettability by the gliding arc plasma technique. In the next stage, polyurethane paints were coated on the treated and untreated PP surfaces. Then, we examined the flame and gliding arc plasma treatments' effect on coating properties of PP bumper, adhesion analysis, water immersion resistance, and sulfuric acid resistance. Finally, high‐pressure carwash test and gloss analysis were conducted on the treated and untreated coated sheets, respectively. [ABSTRACT FROM AUTHOR]

Dry reforming of methane (DRM) over Ni/γ‐MgO catalysts in a coaxial dielectric barrier discharge (DBD) reactor was investigated and compared with DRM without catalysts. Firstly, the catalysts Ni/MgO, Ni/5%CeO2/MgO, and Ni/7%CeO2/MgO were prepared, their characteristics were specified by X‐ray diffraction, and then, they were partially packed into the DBD reactor. Various parameters such as the discharge power, flow rate, and CH4/CO2 molar ratio were explored. The presence of catalysts in the plasma reactor increased the yield and selectivity of H2 and CO. Furthermore, the effect of a reduced catalyst (Ni/7%CeO2/MgO reduced in argon‐hydrogen plasma) was evaluated, showing that CH4 can be converted with activated catalyst without extra power. Activated Ni/7%CeO2/MgO alone was able to convert CH4 to over 99 % for 30 min after reduction. [ABSTRACT FROM AUTHOR]

In this study, dried walnut kernels were processed by radiofrequency low pressure cold plasma (LPCP) treatment using normal air. Dried walnut kernels were treated with LPCP at different powers (20, 30, 40, and 50 W) and at different times (10, 15, and 20 min), and finally compared with the untreated sample. The tests performed in this study included microbial load reduction, decimal reduction time (D‐value), peroxide value, moisture content, texture firmness, and color parameters. The LPCP treated samples compared with the control sample significantly reduced the microbial load (p < 0.05). The highest microbial log reduction was observed in 50 W for 20 min. Total viable count, coliform, and mold log reduction were equal to 1.09, 0.97, and 0.89 log CFU/g, respectively. D‐values were also calculated, with the maximum reduction observed at 50 W. The lowest D‐values for the total count, coliform, and mold were 19.66, 18.25, and 18.18 min, respectively. There was no significant difference between the treated and untreated samples in terms of peroxide value and firmness (p > 0.05). However, the treated samples' moisture content diminished with increasing power and LPCP exposure time (p < 0.05). The result indicated that the LPCP darkened the treated samples' color. Practical Applications: This study demonstrates the potential of low pressure cold plasma applications for the decontamination of dried walnut kernels. It is an appropriate alternative for product disinfection such as nuts, spices, aromatic plants, and other sensitive foods to high‐temperature processing, due to the lack of waste production, low energy consumption, low cost, and keeping the physicochemical properties of products intact. [ABSTRACT FROM AUTHOR]

In this study, the effects of cold plasma and plasma‐activated medium (PAM) are investigated through different treatment times, different intervals between treatment and analysis, and synthesis of helium gas and helium + 0.5% oxygen. The viability of two cancer cell lines including Hela and MDA‐MB‐231, which are related to cervix and breast cancers, respectively, is investigated using the 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyl tetrazolium bromide assay. To study the effect of plasma on normal cells, the corresponding method is used for examination of the normal human fibroblasts. H2O2 showed a higher concentration after direct‐plasma treatment than PAM treatment. Caspase 3, caspase 8, and Bax proteins and the relative Bax/Bcl‐2 ratio are compared in both the direct‐plasma and PAM methods. The results show that the expression level of apoptotic proteins caspase 3 and caspase 8 in direct‐plasma treatment is higher than that in PAM treatment, and the level of relative Bcl‐2/Bax ratio is increased, demonstrating the induction of the apoptosis mechanism. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the efficacy and safety of cold atmospheric plasma (CAP) as a novel therapy for diabetic foot ulcers. This was an investigator-blinded, randomized controlled trial of 14 weeks (6 weeks of treatment and 8 weeks of follow-up). Twenty patients with diabetic foot ulcers were divided into two groups: the control group receiving standard wound care and the plasma group, which received CAP twice a week for six consecutive weeks in addition to standard wound care. The ulcer size, amount of exudate, and wound grading were determined weekly. Cold plasma was produced by applying a high voltage (4.5 kV) and a high frequency (22 kHz) to helium gas. Exudate from wounds treated with CAP showed a significant reduction in the third week after complete treatment (p = 0.039). The wound grading of the ulcers improved by the sixth week (p = 0.019), and the sizes of ulcers significantly decreased in the plasma group at the end of the treatment period (p = 0.007). In this randomized clinical trial, CAP was an effective treatment option for diabetic foot ulcers in terms of wound surface reduction and antibacterial effects., (© 2021 Wiley Periodicals LLC.)