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1.
Food Chem ; 346: 128974, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33465571

RESUMO

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.


Assuntos
Lipase/metabolismo , Lipoxigenase/metabolismo , Gases em Plasma/química , Triticum/enzimologia , Antioxidantes/química , Argônio/química , Nitrogênio/química , Fenóis/química , Temperatura , Triticum/química
2.
Arch Biochem Biophys ; 698: 108726, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33326801

RESUMO

The study investigates the effect of LPDBD (Low Pressure Dielectric Barrier Discharge) (Ar + Air) plasma on seed germination, seedling growth and antioxidant enzyme activity of rice. Rice seeds were treated with LPDBD (Ar + Air) plasma for 2min, 4min, 6min, 8min and 10min. Seed germination rate, seedling growth, total chlorophyll content, enzymatic activity, total soluble sugar and protein concentration were increased in plants grown from the LPDBD (Ar + Air) plasma treated seeds. It was observed that the sprouting of seeds and the growth of seedlings of rice depends on the feed gases used to generate plasma and plasma processing time. In the case of plantlets germinated from the plasma-treated seeds of rice, the H2O2 level was increased significantly both in leaves and roots for 6min, 8min and 10min treatment respectively. No significant change was observed in Nitric Oxide (NO) concentration in seed, leaf, or root of plants grown from LPDBD (Ar + Air) plasma-treated seeds. The amount of total soluble sugar and protein increased significantly in the case of 2min, 4min, 6min, 8min and 10min seed treatment. Although plants exhibited no significant increase in APX activities, but a significant increase of CAT and SOD activity in the leaf and root was found. This study reveals that LPDBD (Ar + Air) plasma is involved in the elevation of ROS species in leaf and root of rice plants which is tightly regulated by the upregulation of CAT activity that ultimately enhances the seed germination and growth of rice plantlets.


Assuntos
Catalase/metabolismo , Oryza/metabolismo , Gases em Plasma/farmacologia , Plântula/metabolismo , Sementes/metabolismo , Superóxido Dismutase/metabolismo , Ar , Argônio/química , Germinação/efeitos dos fármacos , Germinação/fisiologia , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento
3.
J Chromatogr A ; 1625: 461302, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709345

RESUMO

Additives are added to polymers in small concentration to achieve desired application properties widely used to tailor the properties. The rapid diversification of their molecular structures, with often only minute differences, necessitates the development of adequate chromatographic techniques. While modified silica so far is the workhorse as stationary phase we have probed the potential of porous graphitic carbon (HypercarbTM) for this purpose. The results show that the multitude of physicochemical interactions between analyte molecules and the graphitic surface enables separations of polyolefin stabilizers with unprecedented selectivity. To support the chromatographic results the adsorption capability of HypercarbTM for selected antioxidants and UV absorbers has been determined by Raman spectroscopy and argon physisorption measurements. The shift of the Graphite-band in the Raman spectra of HypercarbTM upon infusion with additives correlates with the changes in the Adsorption Potential Distributions. The results of argon physisorption measurements go hand in hand with the chronology of desorption of the additives in liquid chromatography experiments. The elution sequence can be explained by van der Waals or London forces, π-π-interactions and electron lone pair donor-acceptor interactions between the graphite surface and analyte functional groups.


Assuntos
Grafite/química , Polímeros/química , Análise Espectral Raman , Adsorção , Antioxidantes/isolamento & purificação , Argônio/química , Clorofórmio/química , Éteres Metílicos/química , Polienos/química , Porosidade , Fatores de Tempo
4.
Pak J Biol Sci ; 23(3): 248-256, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31944085

RESUMO

BACKGROUND AND OBJECTIVE: Atmospheric pressure plasma jet (APPJ) gained great interest due to its effectiveness as selective non-lethal technique with low operational costs. In this study, argon APPJ system was designed and the generated cold plasma was applied in disinfection of microbial cells. MATERIALS AND METHODS: Argon APPJ was generated by blowing argon through capillary metallic tube inserted in alumina and powered by 8-25 kHz sinusoidal voltage waveform. The plasma applied in inactivation of microbes by direct exposure of cell suspension, approximately 10 mm below jet nozzle, for different intervals. Interference of organics in exposure medium, on lethal activity of plasma was investigated. RESULTS: APPJ jet induced high levels of reactive oxygen (ROS) and nitrogen species (RNS). Jet length increased with applied voltage and flow rate in laminar mode, but decreased with flow rate in turbulent mode. Percent reduction in living cell count was 98.3 and 94.1%, for E. coli and S. aureus suspended in water after 30s of exposure, respectively, with 2.7- and 2-folds increase in plasma lethal activity, as compared with LB broth medium. D-values (Decimal Reduction Time) were increased from 34-333, 37-476 and 139-385 s for E. coli, S. aureus and C. albicans in water and complex liquid organic media, respectively. CONCLUSION: Designed argon APPJ system can be used in disinfection of different microbes. Plasma antimicrobial activity drastically decreased in presence of organic matter. The generated plasma can be promising approach for treatment of diseases, especially caused by antibiotic-resistant pathogens.


Assuntos
Argônio/química , Desinfecção/métodos , Gases em Plasma , Anti-Infecciosos/química , Pressão Atmosférica , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Radicais Livres , Viabilidade Microbiana , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos
5.
Ecotoxicol Environ Saf ; 189: 110015, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31830602

RESUMO

This paper adopts a novel data-processing method of ECSA® based on TG/DSC-MS system to basically study the characteristics of release and conversion of fluorides and cyanides during heat treatment of the spent cathode carbon block (SCCB). All the experiments were conducted at 10 K⋅min-1 heating rate and under Ar or Ar-O2 atmospheres. The results indicate that the release of fluorides was just a steady but slow phase transition process under both Ar and Ar-O2 atmospheres, which can be comparatively accelerated when the carbon material was burnt. The cyanides were effectively decomposed at high temperature and at Ar-O2 atmosphere, with around three quarters of the cyanides being converted to the N2 and nearly a quarter being to the NO. Finally, analysis on the flue gas composition indicates that it had a more complicated composition of CO2, N2, NO, NO2, HCN under Ar-O2 atmosphere but only had a composition of CO2 and NO under Ar atmosphere.


Assuntos
Poluentes Atmosféricos/química , Carbono/química , Cianetos/química , Eletrodos , Fluoretos/química , Poluentes Atmosféricos/análise , Alumínio , Argônio/química , Atmosfera/química , Cianetos/análise , Fluoretos/análise , Temperatura Alta , Metalurgia , Eliminação de Resíduos
6.
Int J Biol Macromol ; 142: 769-777, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31622703

RESUMO

In this research, the influence of different cold plasma treatments was investigated as a novel method for modification of protein film properties. The films were prepared from whey and gluten proteins using solvent casting method and then treated with vacuum low-pressure glow plasma using air and argon gases at 50 KW for 5, 10, and 15 min and further analyzed mechanically and physicochemically. The images of atomic force microscopy (AFM) revealed a significant increase in roughness of whey protein films after plasma treatment, while the roughness of treated gluten films diminished dramatically. Furthermore, the tensile strength of films improved significantly after 10 min of process, from 6.902 to 10.772 MPa and from 1.854 to 2.571 MPa for whey protein and gluten films, respectively. Introduction of functional groups such as CO and OC bonds plus cross link creation was observed by FTIR which could lead to changes in different film features. Although gas permeability of both edible polymers decreased significantly, other parameters including solubility and water vapor permeability of control and plasma treated (PT) films did not show dramatic differences. Therefore, the optimum condition and time of low-pressure glow plasma has the potential for modifying protein films.


Assuntos
Glutens/química , Gases em Plasma/química , Proteínas do Soro do Leite/química , Ar , Argônio/química , Membranas Artificiais , Permeabilidade , Polimerização , Solubilidade , Vapor , Propriedades de Superfície , Resistência à Tração , Fatores de Tempo , Vácuo
7.
Phys Chem Chem Phys ; 21(41): 22857-22868, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31599896

RESUMO

Three low-energy isomers of 9-methylguanine, the amino-oxo (AO) form and two amino-hydroxy (AH1 and AH2) conformers, were trapped from the gas phase into low-temperature argon matrices. The AH1 and AH2 isomers, differing in the orientation of the OH group, were found to transform into each other upon excitation with near-IR light. The population of the AO form of the compound was not changed upon any near-IR irradiation of the matrix samples. Using monochromatic near-IR light, generated by a frequency-tunable laser source, it was possible to selectively induce the AH1 → AH2 or AH2 → AH1 conversion. Photoreversibility of this conformational transformation was then demonstrated. Exposure of matrix-isolated monomers of 9-methylguanine to broadband near-IR light also led to conformational conversions within the amino-hydroxy tautomeric form; the final stage of this process was always the same photostationary state independent of the initial ratio of AH1 and AH2 populations. Spontaneous conformational conversion, transforming the higher-energy AH2 form into the lower-energy AH1 isomer, was observed for matrix-isolated monomers of 9-methylguanine kept in the dark. The mechanism of this process must rely on quantum tunneling of the light hydrogen atom. Irradiation of matrix-isolated 9-methylguanine with UV laser light at λ = 288 or 285 nm led to a substantial consumption of the two AH forms, while the amount of AO isomer remained unchanged. On the other hand, a decrease in the population of the AO isomer occurred upon excitations at shorter wavelengths, λ = 280 or 275 nm. The spectral changes observed after UV-irradiation suggest the generation (and stabilization in the matrix) of a radical species, resulting from the photocleavage of the O-H or N1-H bonds, in the AH or AO isomer, respectively.


Assuntos
Argônio/química , Temperatura Baixa , Guanina/análogos & derivados , Raios Infravermelhos , Raios Ultravioleta , Guanina/química , Isomerismo , Conformação Molecular/efeitos da radiação
8.
Inorg Chem ; 58(18): 12302-12310, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31522510

RESUMO

Photochemistry is a rich source of inspiration for developing alternative methods to functionalize proteins with drug molecules, fluorophores, and radioactive probes. Here, we report the synthesis and photochemical reactivity of a modified diethylenediamine pentaacetic acid chelate that was derivatized with a light-responsive aryl azide group (DTPA-PEG3-ArN3, compound 1). The corresponding nonradioactive and radioactive nat/68Ga3+ and nat/111In3+ complexes of DTPA-PEG3-ArN3 were synthesized and their physical and photochemical properties were studied to evaluate the potential of employing this ligand system in the photochemical synthesis of radiolabeled antibodies. Photodegradation kinetics revealed that irradiation with ultraviolet light (365 nm) induced rapid photoactivation of compound 1 and the metal complexes nat/68Ga-1- and nat/111In-1-. Light-induced reactions were complete in <100 s, with measured first-order rate constants of 0.078 ± 0.045 s-1, 0.093 ± 0.009 s-1, and 0.117 ± 0.054 s-1 (n = 2, per species) for compound 1, natGa-1-, and natIn-1-, respectively. Photochemically induced bioconjugation reactions between DTPA-PEG3-ArN3 and the monoclonal antibody trastuzumab, as well as pre- and postconjugation 68Ga- and 111In-radiolabeling experiments, were performed using either a one-pot or two-step strategy. Both approaches yielded radiolabeled trastuzumab ([68Ga]GaDTPA-azepin-trastuzumab) with average radiochemical conversions of 3.9 ± 1.0% (n = 4, one-pot), and 10.0 ± 1.0% (n = 3, two-step). One-pot radiolabeling reactions with [111In]InCl3 produced the corresponding [111In]InDTPA-azepin-trastuzumab radiotracer in a similar radiochemical conversion of 5.4 ± 0.8% (n = 3). Radiochemical conversions for the desired bimolecular coupling between the chelate and the protein were comparatively low. This observation is likely caused by the high photoinduced reactivity of the compounds and subsequent competition with background reactions. Nevertheless, access to DTPA-PEG3-ArN3 increases the scope of photoradiochemical methods to include metal ions like In3+ that form complexes with higher coordination numbers.


Assuntos
Quelantes/química , Radioisótopos de Gálio/química , Imunoconjugados/química , Radioisótopos de Índio/química , Ácido Pentético/química , Polietilenoglicóis/química , Trastuzumab/química , Argônio/química , Quelantes/síntese química , Luz , Ácido Pentético/síntese química , Fotólise , Polietilenoglicóis/síntese química
9.
Molecules ; 24(18)2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31489896

RESUMO

Structural changes of glycolic acid (GA) complex with nitrogen induced by selective overtone excitation of the νOH mode were followed in argon matrices using FTIR spectroscopy. For the most stable SSC1 complex present in different trapping sites directly upon deposition site, selective changes in the νOH region were achieved upon near-infrared irradiation. Simultaneously, new conformers of the GA…N2 complex were formed, giving rise to several sets of bands in the νOH and νC=O regions of the spectra. Both position and intensity of new absorptions appeared to be highly sensitive on the wavelength of radiation used, as well as on the annealing of the matrix. Based on theoretical calculations at different levels of theory, an assignment of the observed bands is proposed and discussed.


Assuntos
Argônio/química , Glicolatos/química , Modelos Moleculares , Estrutura Molecular , Nitrogênio , Espectroscopia de Infravermelho com Transformada de Fourier , Vibração
10.
Mater Sci Eng C Mater Biol Appl ; 105: 110085, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546386

RESUMO

Bone and cartilage craniofacial defects due to trauma or congenital deformities pose a difficult problem for reconstructive surgeons. Human adipose stem cells (ADSCs) can differentiate into bone and cartilage and together with suitable scaffolds could provide a promising system for skeletal tissue engineering. It has been suggested that nanomaterials can direct cell behavior depending on their surface nanotopographies. Thus, this study examined whether by altering a nanoscaffold surface using radiofrequency to excite gases, argon (Ar), nitrogen (N2) and oxygen (O2) with a single step technique, we could enhance the osteogenic and chondrogenic potential of ADSCs. At 24 h, Ar modification promoted the highest increase in ADSCs adhesion as indicated by upregulation of vinculin and focal adhesion kinase (FAK) expression compared to O2 and N2 scaffolds. Furthermore, ADSCs on Ar-modified nanocomposite polymer POSS-PCU scaffolds upregulated expression of bone markers, alkaline phosphatase, collagen I and osteocalcin after 3 weeks. Cartilage markers, aggrecan and collagen II, were also upregulated on Ar-modified scaffolds at the mRNA and protein level. Finally, all plasma treated scaffolds supported tissue ingrowth and angiogenesis after grafting onto the chick chorioallantoic membrane. Ar promoted greater expression of vascular endothelial growth factor and laminin in ovo compared to O2 and N2 scaffolds as shown by immunohistochemistry. This study provides an important understanding into which surface chemistries best support the osteogenic and chondrogenic differentiation of ADSCs that could be harnessed for regenerative skeletal applications. Argon surface modification is a simple tool that can promote ADSC skeletal differentiation that is easily amenable to translation into clinical practice.


Assuntos
Tecido Adiposo/metabolismo , Argônio/química , Diferenciação Celular , Condrogênese , Nanocompostos/química , Osteogênese , Gases em Plasma/química , Poliuretanos/química , Células-Tronco/metabolismo , Engenharia Tecidual , Tecidos Suporte/química , Tecido Adiposo/citologia , Células Cultivadas , Humanos , Células-Tronco/citologia
11.
J Food Sci ; 84(10): 2876-2882, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31513725

RESUMO

Microwave-powered cold plasma (CP) treatment was evaluated as a means to increase the antioxidant activity, water solubility, and dispersion stability of prickly pear cactus fruit (Opuntia ficus-indica (L.) Mill.) extract. The extract (2 g) was treated at various CP generation powers and treatment times at 25 °C to 28 °C. The antioxidant activity of the prickly pear cactus fruit extract increased by 1.8% and 1.7% after CP treatment at 750 W for 40 min and 856 W for 36 min, respectively. Both the water solubility and dispersion stability (delta backscattering) of the extract increased by 2.4% and 0.1%, respectively, following CP treatment at 644 W for 36 min. These results suggest the potential of CP treatment to increase the applicability of the prickly pear cactus fruit extract and possibly other insoluble natural antioxidant compounds in foods by improving their antioxidant activities and solubility in water. PRACTICAL APPLICATION: Prickly pear cactus fruit is a functional food with a high antioxidant concentration. This study demonstrated that cold plasma treatment improved the water solubility and dispersion stability of prickly pear cactus fruit extract without altering or improving its antioxidant activity. The obtained results suggested the potential of applying cold plasma technology to improve the applicability of the extract, which is difficult to solubilize in food systems, to various processed foods.


Assuntos
Antioxidantes/química , Argônio/química , Manipulação de Alimentos/métodos , Opuntia/química , Extratos Vegetais/química , Gases em Plasma/química , Frutas/química , Alimento Funcional , Solubilidade
12.
Molecules ; 24(18)2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31500265

RESUMO

Molecular complexes between glycolic acid and nitrogen were studied in a low-temperature argon matrix with FTIR spectroscopy, and supported by MP2 and BLYPD3 calculations. The calculations indicate 11 and 10 stable complex structures at the MP2 and BLYPD3 levels of theories, respectively. However, only one hydrogen-bonded complex structure involving the most stable SSC conformer of glycolic acid was found experimentally, where the nitrogen molecule is bound with the carboxylic OH group of the SSC conformer. The complex shows a rich site structure variation upon deposition of the matrix in different temperatures and upon annealing experiments, which provide interesting prospects for site-selective chemistry.


Assuntos
Argônio/química , Glicolatos/química , Nitrogênio/química , Química Computacional/métodos , Ligação de Hidrogênio , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
13.
J Xray Sci Technol ; 27(5): 857-870, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31282467

RESUMO

Anomalously high x-ray scattering at a wavelength of 0.154 nm by super-polished substrates of fused silica, which were etched by the argon ions with the energy of 300 eV, is detected. The scattering intensity increases monotonically with increasing of the etching depth. The effect is explained by the scattering on the volume inhomogeneities with the lateral size greater than 0.5 µm of the subsurface "damaged" layer. The concentration of volume inhomogeneities increases with the increase of the fluence of argon ions, but the concentration of implanted argon atoms in the layer quickly reaches the maximum value and then begins a trend of going down. The thickness of the "damaged" layer is approximately equal to the penetration depth of the Ar atoms and can be directly determined from the x-ray specular reflection. It is shown that the presence of volume inhomogeneities of the subsurface "damaged" layer does not affect the geometric roughness of the surface. The observed effect imposes limitations on the usage of grazing incidence x-ray optics without reflective coatings and of the diffuse x-ray scattering (DXRS) method for studying the substrate roughness. A new method that potentially enables to evaluate the applicability of the DXRS method in practice is proposed.


Assuntos
Argônio/química , Imagem Óptica/instrumentação , Dióxido de Silício/química , Difração de Raios X/instrumentação , Íons , Propriedades de Superfície
14.
Biomed Res Int ; 2019: 4847932, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31321236

RESUMO

Hydroxyapatite/graphene oxide/platinum (HA/GO/Pt) nanocomposite was synthesized and electrodeposited on a pure zirconium substrate. The coated zirconium was annealed at 200, 300, 400, and 600°C in vacuum furnace in presence of argon gas. The structure and morphology of the coated samples were characterized. Biocompatibility and wear and corrosion resistances of specimens were examined. The result of corrosion tests shows that the graphene into HA/Pt composites significantly improves their corrosion resistance. The wear tests results of uncoated and coated samples before and after annealing show that coated samples annealed at 300°C had better wear resistance compared with uncoated and coated samples at other temperatures. Furthermore, the biocompatibility test shows that the coatings improved the cell attachment and proliferation compared to the pure zirconium substrate.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Grafite/química , Nanocompostos/química , Osteoblastos/efeitos dos fármacos , Argônio/química , Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/química , Durapatita/síntese química , Durapatita/química , Grafite/síntese química , Grafite/farmacologia , Humanos , Teste de Materiais , Nanocompostos/administração & dosagem , Platina/química , Especificidade por Substrato , Propriedades de Superfície , Titânio/química , Zircônio/química
15.
J Food Sci ; 84(7): 1871-1880, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31218691

RESUMO

Impact of dielectric barrier discharge high-voltage cold atmospheric plasma (DBD-HVCAP) generated with the mixture of oxygen and argon (10:90) for various treatment times (2.5 to 10 min) on the qualities of Asian sea bass slices during 4 °C storage was investigated. Microbial load of slices treated with DBD-HVCAP were lower than the control. The efficacy of bacteria reduction by DBD-HVCAP was dependent on the treatment times (P < 0.05). Total viable bacteria count (TVBC) was more than 6.0 Log CFU/g at day 6 for the control kept in air. Slices treated with DBD-HVCAP for all treatment times used had TVBC lower than the limit at day 12. Total volatile nitrogen base content (TVNB) as well as trimethylamine (TMA) content in slices treated with DBD-HVCAP were lower than that of the control throughout the storage. TVNB as well as TMA contents were lower in HVCAP treated slices in a treatment time-dependent manner. Nevertheless, lipid oxidation in samples treated with DBD-HVCAP was higher than that of the control. Polyunsaturated fatty acids were decreased in slices treated with DBD-HVCAP for more than 5 min after 12 days of storage. Therefore DBD-HVCAP treatment for 5 min was demonstrated to be potential means for increasing the shelf-life of Asian sea bass slices with minimal negative effect on chemical and sensory properties, in which they could be stored longer than 12 days at 4 °C. PRACTICAL APPLICATION: Microbial inactivation capacity of dielectric barrier discharge high-voltage cold atmospheric plasma (DBD-HVCAP) has been documented with limited information on its application in extending the shelf-life of foods. DBD-HVCAP was demonstrated as an innovative technology for extending the shelf-life of Asian sea bass slices, which could be implemented in seafood industries for assuring safety and extending shelf-life of products. The shelf-life of the slices treated with DBD-HVCAP was extended to 12 days of storage at 4 °C as compared to the 6 days of the untreated counterpart.


Assuntos
Bass/microbiologia , Produtos Pesqueiros/análise , Conservação de Alimentos/métodos , Gases em Plasma/farmacologia , Animais , Argônio/química , Argônio/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Produtos Pesqueiros/microbiologia , Armazenamento de Alimentos , Oxigênio/química
16.
J Sci Food Agric ; 99(12): 5491-5498, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31095729

RESUMO

BACKGROUND: During planting, storage and transportation of maize excessive amounts of pesticides are used to ensure production, resulting in pesticide residues on the maize that can threaten human health. Plasma, compared with other technologies, has been widely regarded as a green, safe and promising technology for surface decontamination to ensure maize safety and quality. RESULTS: The aim of this study is to discuss plasma effects on the degradation of chlorpyrifos and carbaryl on maize surface and the changes of treated maize quality. Results achieved the largest degradation efficiency of chlorpyrifos and carbaryl, up to 91.5% and 73.1%, respectively. The physical changes of maize were observed by scanning electron microscopy (SEM), showing a decrease in contact angle, an increase in surface free energy and polar component, leading to improved hydrophilicity of the treated maize. There was no significant change of vitamin B2 content of maize. A significant increase of acid value and decrease of moisture content and starch content were observed within acceptable limits. CONCLUSION: It is reasonable to believe that argon plasma treatment enhances the edible safety of maize while maintaining maize quality. © 2019 Society of Chemical Industry.


Assuntos
Argônio/farmacologia , Resíduos de Praguicidas/química , Gases em Plasma/farmacologia , Zea mays/química , Zea mays/efeitos dos fármacos , Argônio/química , Carbaril/química , Clorpirifos/química , Contaminação de Alimentos/análise , Cinética , Controle de Qualidade , Riboflavina/análise , Amido/análise
17.
Tissue Cell ; 58: 121-129, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31133240

RESUMO

Surface modification is an important step in making a synthetic polymer cytocompatible. We have previously reported improved cytocompatibility of immortalized human keratinocytes (HaCaT) with the otherwise bioinert fluorinated ethylene propylene (FEP) upon treatment with argon plasma discharge. In this article, we show that FEP modified with Ar plasma with the power of 3 and 8 W for 40 and 240 s served as a suitable material for cultivation of primary human dermal fibroblasts (HDF), which showed significantly improved proliferation and spreading comparable to standard tissue culture polystyrene. We also evaluated focal adhesions formed by HDF cells on modified FEP, which were far more numerous compared to pristine FEP. Moreover, we attempted spontaneous osteogenic differentiation of adipose-derived mesenchymal stem cells modified with human telomerase reverse transcriptase on Ar plasma-modified FEP. While the spontaneous osteogenic differentiation was unsuccessful, the cells were able to adhere and differentiated on tested matrices upon the administration of osteodifferentiation medium. These combined findings suggest that the treatment of FEP with Ar plasma comprises and efficient method to enable the adhesion and proliferation of various cell types on an otherwise largely bioinert material.


Assuntos
Tecido Adiposo/metabolismo , Argônio/química , Derme/metabolismo , Fibroblastos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Gases em Plasma/química , Politetrafluoretileno/análogos & derivados , Tecido Adiposo/citologia , Adesão Celular , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Derme/citologia , Fibroblastos/citologia , Humanos , Células-Tronco Mesenquimais/citologia , Osteogênese , Politetrafluoretileno/química
18.
PLoS One ; 14(4): e0214509, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30933989

RESUMO

Cadmium (Cd) contamination in plant-derived food is a big concern. This study examines whether and how Ar/O2 and Ar/Air plasma techniques lead to Cd detoxification in wheat. Treatment with Ar/O2 and Ar/Air changed the seed surface and decreased the pH of seeds as well as the cultivation media. Generally, plants subjected to Cd treatment from seeds treated with Ar/O2and Ar/Air plasma showed considerable progress in morphology and total chlorophyll synthesis compared to Cd-treated wheat, suggesting that plasma technology is effective for Cd detoxification. Furthermore, Ar/O2 and Ar/Air plasma treated plants showed a significant decrease in root and shoot Cd concentration, which is consistent with the reduced expression of Cd transporters in the root (TaLCT1 and TaHMA2) compared with the plants not treated with plasma in response to Cd stress. This Cd inhibition is possibly accomplished by the decrease of pH reducing the bioavailability of Cd in the rhizosphere. These observations are in line with maintenance of total soluble protein along with reduced electrolyte leakage and cell death (%) in root and shoot due to Ar/O2 and Ar/Air treatments. Further, Cd-induced elevated H2O2 or oxidative damage in tissues was mainly diminished through the upregulation of antioxidant enzymes (SOD and CAT) and their corresponding genes (TaSOD and TaCAT) induced by Ar/O2 and Ar/Air plasma. Grafting results suggest that root originating nitric oxide signal possibly drives the mechanisms of Cd detoxification due to plasma treatment in wheat. These findings provide a novel and eco-friendly use of plasma technology for the mitigation of Cd toxicity in wheat plants.


Assuntos
Cádmio/toxicidade , Triticum/efeitos dos fármacos , Triticum/metabolismo , Ar , Antioxidantes/química , Argônio/química , Ascorbato Peroxidases/química , Catalase/química , Morte Celular , Clorofila/química , Meios de Cultura , Eletrólitos , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Óxido Nítrico/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Rizosfera , Sementes/efeitos dos fármacos , Transdução de Sinais , Superóxido Dismutase/química
19.
J Nanobiotechnology ; 17(1): 51, 2019 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-30954085

RESUMO

BACKGROUND: Children born with a small or absent ear undergo surgical reconstruction to create a suitable replacement using rib cartilage. To overcome the donor site morbidity and long-term pain of harvesting rib cartilage, synthetic materials can be a useful alternative. Medpor, is the currently used synthetic polyethylene material to replace missing facial cartilage but unfortunately it has high levels of surgical complications including infection and extrusion, making it an unsuitable replacement. New materials for facial cartilage reconstruction are required to improve the outcomes of surgical reconstruction. This study has developed a new nanomaterial with argon surface modification for auricular cartilage replacement to overcome the complications with Medpor. RESULTS: Polyurethanes nanocomposites scaffolds (PU) were modified with argon plasma surface modification (Ar) and compared to Medpor in vitro and in vivo. Ar scaffolds allowed for greater protein adsorption than Medpor and PU after 48 h (p < 0.05). Cell viability and DNA assays demonstrated over 14-days greater human dermal fibroblast adhesion and cell growth on Ar than PU and Medpor nanocomposites scaffolds (p < 0.05). Gene expression using RT-qPCR of collagen-I, fibronectin, elastin, and laminin was upregulated on Ar scaffolds compared to Medpor and PU after 14-days (p < 0.05). Medpor, unmodified polyurethane and plasma modified polyurethane scaffolds were subcutaneously implanted in the dorsum of mice for 12 weeks to assess tissue integration and angiogenesis. Subcutaneous implantation of Ar scaffolds in mice dorsum, demonstrated significantly greater tissue integration by H&E and Massons trichrome staining, as well as angiogenesis by CD31 vessel immunohistochemistry staining over 12-weeks (p < 0.05). CONCLUSIONS: Argon modified polyurethane nanocomposite scaffolds support cell attachment and growth, tissue integration and angiogenesis and are a promising alternative for facial cartilage replacement. This study demonstrates polyurethane nanocomposite scaffolds with argon surface modification are a promising biomaterial for cartilage tissue engineering applications.


Assuntos
Argônio/química , Cartilagem da Orelha , Nanocompostos/química , Gases em Plasma/química , Poliuretanos/química , Adsorção , Animais , Materiais Biocompatíveis/química , Colágeno Tipo I/química , Elastina/química , Fibroblastos/citologia , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Tamanho da Partícula , Polietilenos/química , Engenharia Tecidual/métodos , Tecidos Suporte/química
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