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1.
Food Chem ; 351: 129285, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-33640775

RESUMEN

Macro- and microelement determination in chocolate bars by microwave-induced plasma optical emission spectrometry (MIP OES) was evaluated after microwave-assisted sample digestion. Optimization of the sample digestion was carried out, and the recommended conditions were obtained at a temperature of 190 °C, with a digestion time of 40 min and in a mixture constituted by 2.3 mL of nitric acid, 1.0 mL of hydrogen peroxide and 4.7 mL of water. The method was applied in the analysis of chocolate bars, and the concentration ranges of the elements determined were (in mg kg-1): Ca (653-3096); Cr (<0.6-2.8); Cu (<0.16-19.5); Fe (<1.6-227); Mg (147-2775); K (3554-8573); Mn (<0.03-25.2); Na (45.6-1095); Ni (3.2-10.2); P (1111-22594) and Zn (4.8-33.3). The association of the proposed microwave-assisted acid digestion with the MIP OES technique was adequate for multi-element determination in chocolate bars for routine analysis.


Asunto(s)
Chocolate/análisis , Microondas , Gases em Plasma/química , Espectrofotometría/métodos , Digestión , Calor , Peróxido de Hidrógeno/química , Límite de Detección , Metales/análisis , Ácido Nítrico/química , Agua/química
2.
Food Chem ; 349: 129159, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33545604

RESUMEN

The effect of dry heat (DH, 130 °C, 1, 3 and 9 h), cold plasma (CP, 40 V, 1, 5 and 10 min) and their combination (D-P) treatment on the structure, physicochemical and digestive properties of red adzuki bean starch were studied. The results showed that DH or CP had slight change in morphology while diffraction pattern of starch was remained. With the extension of treated time of DH and CP, the amylose content, crystallinity, molecular weight, short-range order, the long chain of amylopectin, enthalpy value, swelling power, digestibility were reduced, while gelatinization temperatures, the short chain of amylopectin and solubility were increased. The D-P had deeper modification than the single treatment. The combination of dry heat and cold plasma is a simple and green method to improve the starch structure and enhance starch properties and this modified starch could be implemented to tailor starch to the desired food applications.


Asunto(s)
Frío , Digestión , Calor , Gases em Plasma/química , Almidón/química , Almidón/metabolismo , Vigna/química , Manipulación de Alimentos , Gelatina/química , Peso Molecular , Solubilidad , Termodinámica
3.
Chem Biol Interact ; 338: 109403, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33582111

RESUMEN

Cells death is indispensable for embryonic development, tissue homeostasis, and the elimination of cancer, virally infected, or degenerated cells in multicellular organisms. It occurs not only via existing modes but also via unidentified modes, whose elucidation requires. Exposure to non-thermal atmospheric pressure plasma (NTAPP) has been demonstrated to induce cell death, probably because of its ability to generate reactive oxygen species (ROS). However, the mode of this cell death and its underlying mechanism remained elusive. Here we show cell death occurring in a novel and distinctive mode different from apoptosis and necrosis/necroptosis through a mechanism that ROS mediate the loss of the translation inhibitor Programmed cell death 4 (Pdcd4) when cells are cultured in solutions activated by NTAPP irradiation. Thus, our study performed with NTAPP-activated solutions may provide insight into the existence of the atypical cell death in cells and some features of its distinguishing mode and underlying mechanism.


Asunto(s)
Gases em Plasma/farmacología , Biosíntesis de Proteínas , Especies Reactivas de Oxígeno/metabolismo , Proteínas Reguladoras de la Apoptosis , Muerte Celular/efectos de los fármacos , Células HeLa , Humanos , Biosíntesis de Proteínas/efectos de los fármacos , Proteínas de Unión al ARN
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(2): 182-189, 2021 Feb 09.
Artículo en Chino | MEDLINE | ID: mdl-33557503

RESUMEN

Objective: To study the influence of non-thermal atmospheric pressure plasma (NTAPP) on dentine surface temperature, wettability and morphology of collagen fibrils under different treatment condition. Methods: Helium was used as the operating gas at the flow rate of 3, 4, 5 L/min respectively. The plasma jet was operated at various input power of 8, 9, 10, 11 W. Thermal accumulation on human dentine surface (6 specimens per group, acquired from Department of Stomatology, The First Affiliated Hospital of Xi'an Medical University and Department of Stomatology, The Second Affiliated Hospital of Xi'an Medical University) of each group was measured continuously at 5 s intervals for 60 s by infrared thermography. Mean values were calculated and temperature curves were drawn. Dentine surface contact angles were measured after NTAPP treatment for 5, 10, 15, 20 s with gas flow rate and input power described above. The micro structure of the collagen fibrils of the negative control group (without NTAPP treatment) and NTAPP treatment groups (5 L/min gas flow rate, input power of 8, 9, 10, 11 W and treating time for 5, 10, 15, 20 s) was observed by field emission scanning electron microscopy (FE-SEM). All data were analyzed by SPSS 18.0. Results: Input power, gas flow and treatment time all showed significant influences on dentine surface temperature and wettability (P<0.01). Dentine temperature rose along with time. The greater input power was, the higher dentine temperature was. The greater gas flow rate was, the faster the temperature rose. Dentine surface temperature reached the highest point of (35.10±0.24) ℃ with NTAPP treatment for 60 s, at input power of 11 W and flow rate of 5 L/min. The contact angles of each experimental group decreased with time, and significant differences were found in the contact angles between the experimental groups and the negative control group (75.57°±1.45°). The contact angles showed a decreasing trend as the input power and the gas flow rate increased. The contact angles reached the lowest point of 13.19°±2.01° with NTAPP treatment for 20 s, at input power of 10 W and flow rate of 5 L/min. The FE-SEM results showed that, along with the increase of input power and extension of time, the demineralized collagen fibrils were destroyed in varying degrees. The collagen fibrils were curled, fractured, fused, and even disappeared. Conclusions: NTAPP could significantly increase the surface temperature, modify dentine wettability and alter the micro structure, which was significantly influenced by input power, gas flow rate and treating time.


Asunto(s)
Dentina , Gases em Plasma , Humanos , Microscopía Electrónica de Rastreo , Plasma , Propiedades de Superficie
5.
Food Chem ; 350: 129195, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-33636620

RESUMEN

This study investigated the effect of plasma-activated liquid (PAL) including plasma-activated water (PAW) and plasma-activated buffer solution (PABS) for the reduction of chlorothalonil (CTL) and thiram (THM) pesticide residues on tomato fruit. Results revealed that the PAL obtained by using atmospheric air as the feed gas, CTL residues were decreased to 85.3% and 74.2% and THM residues decreased to 79.47 and 72.21% after treatments with PAW10 and PABS10, respectively, and increasing the activation time caused a significant reduction in fungicide residues. In addition, CTL and THM residues were also decreased while increasing the activation time of PAL using Ar/O2 as the feed gas, the concentrations of the CTL residues were decreased to 75.07 and 69.89% for PAW10 and PABS10, respectively and THM residues decreased to 65.89 and 61.91% for PAW10 and PABS10, respectively. Oxidation-reduction potential (ORP) and electrical conductivity (EC) were increased significantly after plasma treatment, while pH values of both solutions were decreased significantly with activation time. NO3- and NO2- concentrations of PAW increased significantly, while for PABS, NO3- concentration decreased but NO2-, with increasing the plasma activation time. Additionally, washing with PAW and PABS caused no notable negative impact on tomato fruit. Results confirmed that PAL treatments showed a significant reduction of CTL and THM fungicide residues (p < 0.05) in tomato without affecting the quality.


Asunto(s)
Frutas/química , Fungicidas Industriales/química , Lycopersicon esculentum/química , Gases em Plasma/química , Agua/química , Tampones (Química) , Residuos de Plaguicidas/análisis , Soluciones
6.
Food Chem ; 351: 129278, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-33631612

RESUMEN

The poor gel strength and microbial infection of conventional chicken myofibrillar protein (CMP) gels have severely limited the application. Here, plasma activated water (PAW) instead of normal water was used to prepare CMP gels. PAW prepared by treating deionized water with plasma jet was incubated with CMPs and followed by heating to prepare CMP gels. Effects of PAW on CMP gels were assessed in terms of basic physicochemical properties, network structure, and antibacterial activity. The results showed that PAW treatment accelerated the aggregation of CMPs and increased the strength and water holding capacity of CMP gels. Due to the presence of NO and NO2 free radicals in PAW, the prepared CMP gels were endowed with antibacterial activity against Salmonella Enteritidis and Staphylococcus aureus. The new method of PAW-induced CMP gels will have the prospect of improving the quality of gels and extending the shelf life of chicken gel products.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Pollos , Proteínas Musculares/química , Proteínas Musculares/farmacología , Gases em Plasma/química , Agua/química , Animales , Geles
7.
ACS Appl Mater Interfaces ; 13(3): 3631-3644, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33448783

RESUMEN

Three-dimensional (3D) scaffolds with optimum physicochemical properties are able to elicit specific cellular behaviors and guide tissue formation. However, cell-material interactions are limited in scaffolds fabricated by melt extrusion additive manufacturing (ME-AM) of synthetic polymers, and plasma treatment can be used to render the surface of the scaffolds more cell adhesive. In this study, a hybrid AM technology, which combines a ME-AM technique with an atmospheric pressure plasma jet, was employed to fabricate and plasma treat scaffolds in a single process. The organosilane monomer (3-aminopropyl)trimethoxysilane (APTMS) and a mixture of maleic anhydride and vinyltrimethoxysilane (MA-VTMOS) were used for the first time to plasma treat 3D scaffolds. APTMS treatment deposited plasma-polymerized films containing positively charged amine functional groups, while MA-VTMOS introduced negatively charged carboxyl groups on the 3D scaffolds' surface. Argon plasma activation was used as a control. All plasma treatments increased the surface wettability and protein adsorption to the surface of the scaffolds and improved cell distribution and proliferation. Notably, APTMS-treated scaffolds also allowed cell attachment by electrostatic interactions in the absence of serum. Interestingly, cell attachment and proliferation were not significantly affected by plasma treatment-induced aging. Also, while no significant differences were observed between plasma treatments in terms of gene expression, human mesenchymal stromal cells (hMSCs) could undergo osteogenic differentiation on aged scaffolds. This is probably because osteogenic differentiation is rather dependent on initial cell confluency and surface chemistry might play a secondary role.


Asunto(s)
Células Madre Mesenquimatosas/citología , Gases em Plasma/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Adhesión Celular , Línea Celular , Proliferación Celular , Humanos , Osteogénesis , Silanos/química , Compuestos de Vinilo/química , Humectabilidad
8.
Food Chem ; 346: 128974, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33465571

RESUMEN

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.


Asunto(s)
Lipasa/metabolismo , Lipooxigenasa/metabolismo , Gases em Plasma/química , Triticum/enzimología , Antioxidantes/química , Argón/química , Nitrógeno/química , Fenoles/química , Temperatura , Triticum/química
9.
Am J Vet Res ; 82(2): 118-124, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33480278

RESUMEN

OBJECTIVE: To determine whether a stainless steel implant sterilized with a novel cold atmospheric plasma sterilization (CAPS) device adversely affects local tissues in rabbits and whether CAPS was as effective as steam sterilization with an autoclave to inactivate Pasteurella multocida. ANIMALS: 31 healthy New Zealand White rabbits. PROCEDURES: Steam-autoclaved stainless steel implants inoculated with P multocida underwent a second steam autoclave sterilization (AIA) or CAPS (AICAPS). One AIA implant and 3 AICAPS implants were randomly placed subcutaneously at 4 sites in 21 rabbits (84 implants). These rabbits were monitored daily for 5 days for evidence of systemic illness and local tissue reactions at the implantation sites and then euthanized. Samples were taken from each implant site for bacterial culture and histologic examination. RESULTS: Cultures of samples obtained from all sites were negative for bacterial growth. No significant difference was observed in mean skin thickness or erythema between AIA and AICAPS implant sites on any observed day. Also, individual histologic grades for the epidermis, dermis, subcutis, and muscle and total histologic grade were not significantly different between AIA and AICAPS implant sites. CONCLUSIONS AND CLINICAL RELEVANCE: Cold atmospheric plasma sterilization was noninferior to steam sterilization of P multocida-contaminated stainless steel implants in the rabbits in the present study. However, studies of the efficacy of CAPS for inactivation of other important bacteria are needed.


Asunto(s)
Cuerpos Extraños , Pasteurella multocida , Gases em Plasma , Animales , Cuerpos Extraños/veterinaria , Plasma , Conejos , Esterilización
10.
Chemosphere ; 271: 129575, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33460902

RESUMEN

Non-thermal plasma (NTP) combined with zinc ferrite-reduced graphene oxide (ZnFe2O4-rGO) nanocomposites were used for the degradation of aqueous methylparaben (MeP). ZnFe2O4-rGO nanocomposites were prepared using the hydrothermal method, with the structure and photoelectric properties of nanocomposites then characterized. The effects of discharge power, initial MeP concentration, initial pH, and air flow rate on MeP degradation efficiency were investigated, and the multi-catalytic mechanism and MeP degradation pathways were established. Results showed that ZnFe2O4-rGO nanocomposites with a 10%:90% mass ratio of GO:ZnFe2O4 had an optimal catalytic effect. The MeP degradation efficiency of NTP combined with ZnFe2O4-rGO (10 wt%), was approximately 25% higher than that of NTP alone. Conditions favorable for MeP degradation included higher discharge power, lower MeP concentration, neutral pH value, and higher air flow rate. The degradation of MeP by NTP combined with ZnFe2O4-rGO nanocomposites followed pseudo-first-order kinetics. O2•-, •OH, H2O2, and O3 were found to play important roles in the MeP degradation, as part of the multi-catalytic mechanism of NTP combined with ZnFe2O4-rGO nanocomposites. MeP degradation pathways were proposed based on the degradation intermediates detected by gas chromatography mass spectrometry, including demethylation, hydroxylation, carboxylation, ring-opening, and mineralization reactions. The prepared ZnFe2O4-rGO nanocomposites provide an approach for improved contaminant degradation efficiency, with reduced energy consumption in the NTP process.


Asunto(s)
Grafito , Nanocompuestos , Gases em Plasma , Parabenos
11.
Bioresour Technol ; 323: 124621, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33412497

RESUMEN

In this study, the long-acting mechanism of reactive species was investigated for enhanced ethanol production of Saccharomyces cerevisiae. The results indicated that short-lifetime active species from gas phase plasma dissolved into various liquid microenvironments with different media (water, buffer, medium, and cells), forming different types and amounts of reactive species in multi-scale microenvironments, such as extracellular reactive nitrogen species, endocellular reactive oxygen and nitrogen species. The sustained elevation of cytoplasm calcium concentration with treatment time depended on the activated calcium channels of Cch1p/Mid1p in cell membrane and Yvc1p in vacuole membrane by these species. Accordingly, the Ca2+ increase promoted the H+-ATPase expression. Consequently, 75.6% ATP hydrolysis induced about 5 fold NADH increase compared with the control. Ultimately, the bioethanol yield increased by 34.2% compared to the control. These results promote the development of atmospheric cold plasma as a promising bio-process enhancement technology for improved target product yields of microbes in fermentation industry.


Asunto(s)
Gases em Plasma , Proteínas de Saccharomyces cerevisiae , Etanol , Fermentación , Plasma/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
12.
Food Chem ; 340: 128198, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33032147

RESUMEN

In this study, potential of dielectric-barrier discharge (DBD) plasma treatment (40 kV, 12 kHz at 1, 2, 3 and 4 min) to eliminate soybean agglutinin (SBA) activity was investigated in a SBA model system and soymilk. The plasma treatment decreased the SBA in the model system and hemagglutination activity was decreased by 87.31%. SDS-PAGE analysis confirmed the degradation of the SBA polypeptide chain. The multi-spectroscopic analysis revealed a two-stage structure alteration in the SBA upon exposure to the plasma treatment. Oxidation of NH-/NH2- at the peptide bond disrupted the hydrogen bonds and altered the secondary structure of SBA. Further oxidation of aromatic amino acid, cleavage of peptide bonds and the breakage of polypeptide led to the SBA fragmentation and complete unfolding of the protein. The SBA inactivation by the plasma treatment was confirmed in soymilk. Plasma treatment is a promising technology for the elimination of SBA in soybean product.


Asunto(s)
Lectinas de Plantas/química , Gases em Plasma/química , Proteínas de Soja/química , Impedancia Eléctrica , Enlace de Hidrógeno , Oxidación-Reducción , Estructura Secundaria de Proteína , Leche de Soja/química
13.
J Food Sci ; 86(1): 68-77, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33336377

RESUMEN

Currently, there has been a surge of interest in revealing the interactions between plasma and food matrices. In this study, we investigated the impacts of atmospheric cold plasma (ACP) treatment on the structural, physicochemical and allergenic characteristics of soybean protein isolate (SPI). SPI dispersions were subjected to ACP treatments at different frequencies (80 to 100 Hz) and durations (1 to 10 min) to investigate the effects of exposing conditions. Results showed that ACP induced reactive oxygen species-mediated oxidation of soy proteins, resulting in modifications in the secondary and ternary structures of SPI. As a consequence, functional properties of SPI, such as emulsifying (56 to 168%, compared with control) and foaming properties (60 to 194%) were influenced by varying degrees. In addition, under certain circumstance (120 Hz, 5 min), the IgE-binding level of SPI was decreased by up to 75%, when compared to the control. Moderate treatment yielded products with improved functionality and reduced allergenicity, while extensive exposure induced a loss of vendibility due to protein aggregation. PRACTICAL APPLICATION: In this study, we demonstrated for the first time, that plasma species reacted with soybean proteins, resulting in spatial structural changes which are closely related with protein functionality and allergenicity. ACP interacts with macromolecules in aqueous systems and thus can be an alternative and promising nonthermal approach in modifying soybean proteins, whereas the exact role of different processing parameters needs to be well-elaborated.


Asunto(s)
Alérgenos/análisis , Manipulación de Alimentos/métodos , Proteínas de Soja/química , Proteínas de Soja/inmunología , Fenómenos Químicos , Emulsiones/química , Oxidación-Reducción , Gases em Plasma , Conformación Proteica , Especies Reactivas de Oxígeno/química , Agua/química
14.
Arch Biochem Biophys ; 698: 108726, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33326801

RESUMEN

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.


Asunto(s)
Catalasa/metabolismo , Oryza/metabolismo , Gases em Plasma/farmacología , Plantones/metabolismo , Semillas/metabolismo , Superóxido Dismutasa/metabolismo , Aire , Argón/química , Germinación/efectos de los fármacos , Germinación/fisiología , Oryza/efectos de los fármacos , Oryza/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Semillas/efectos de los fármacos , Semillas/crecimiento & desarrollo
15.
Food Chem ; 338: 127826, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32810815

RESUMEN

This study aimed to evaluate the mutagenicity and oral acute toxicity of winter mushroom powder (PW) treated by atmospheric non-thermal plasma (ANP). Winter mushroom powder without plasma treatment (CW) containing an equivalent amount of sodium nitrite as PW was used as a control. The Ames test revealed that the number of revertant colonies did not significantly increase compared to that in the control. Acute toxicity was assessed in rats that were fed a single dose of winter mushroom powder (5000 mg/kg body weight). Results of the acute toxicity test revealed no remarkable clinical symptoms in any of the rats. No significant difference was observed in of the serum biochemical parameters between the treatments. Regardless of the ANP treatment, mild histological changes were observed in few rats in all groups. Therefore, it is concluded that ANP treatment did not cause any mutagenicity or acute toxicity in the winter mushroom.


Asunto(s)
Flammulina/química , Industria de Procesamiento de Alimentos/métodos , Polvos/toxicidad , Administración Oral , Animales , Masculino , Pruebas de Mutagenicidad , Gases em Plasma , Polvos/administración & dosificación , Polvos/química , Ratas Sprague-Dawley , Pruebas de Toxicidad Aguda
16.
Int J Food Microbiol ; 337: 108948, 2021 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-33197682

RESUMEN

Novel processing methods such as cold atmospheric plasma (CAP) and natural antimicrobials like nisin, are of interest to replace traditional food decontamination approaches as, due to their mild nature, they can maintain desirable food characteristics, i.e., taste, texture, and nutritional content. However, the microbial growth characteristics (planktonic growth/surface colonies) and/or the food structure itself (liquid/solid surface) can impact the inactivation efficacy of these novel processing methods. More specifically, cells grown as colonies on a solid(like) surface experience a completely different growth environment to cells grown planktonically in liquid, and thus could display a different response to novel processing treatments through stress adaptation and/or cross protection mechanisms. The order in which combined treatments are applied could also impact their efficacy, especially if the mechanisms of action are complementary. This work presents a fundamental study on the efficacy of CAP and nisin, alone and combined, as affected by food system structure. More specifically, Listeria innocua was grown planktonically (liquid broth) or on a viscoelastic Xanthan gum gel system (1.5% w/v) and treated with CAP, nisin, or a combination of the two. Both the inactivation system, i.e., liquid versus solid(like) surface and the growth characteristics, i.e., planktonic versus colony growth, were shown to impact the treatment efficacy. The combination of nisin and CAP was more effective than individual treatments, but only when nisin was applied before the CAP treatment. This study provides insight into the environmental stress response/adaptation of L. innocua grown on structured systems in response to natural antimicrobials and novel processing technologies, and is a step towards the faster delivery of these food decontamination methods from the bench to the food industry.


Asunto(s)
Antibacterianos/farmacología , Manipulación de Alimentos/métodos , Listeria/efectos de los fármacos , Nisina/farmacología , Gases em Plasma/farmacología , Recuento de Colonia Microbiana , Microbiología de Alimentos , Listeria/crecimiento & desarrollo , Modelos Biológicos , Pasteurización/métodos
17.
J Sci Food Agric ; 101(2): 424-432, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32648588

RESUMEN

BACKGROUND: Pesticides have been widely used to control pests on agricultural products in China, and large amounts of pesticide residues have caused a serious threat to human health. Thus, developing a high-efficiency pesticide degradation method for fresh vegetables represents a great challenge. The present study investigated the effects of dielectric barrier discharge (DBD) plasma on the degradation of malathion and chlorpyrifos in aqueous solutions and on lettuces. RESULTS: DBD treatment significantly degraded malathion and chlorpyrifos in water and on lettuce. After cold plasma treatment at 80 kV for 180 s, the degradation efficiency of malathion (0.5 µg mL-1 ) and chlorpyrifos (1.0 µg mL-1 ) in aqueous solutions reached 64.6% and 62.7%, respectively. The degradation intermediates were explored by HPLC-mass spectrometry and the DBD plasma degradation pathways of malathion and chlorpyrifos were proposed. There was no significant damage to the quality of lettuces, including color and chlorophyll content, after plasma treatment. Ascorbic acid decreased significantly during long-term treatment with DBD plasma. To ensure the quality of lettuces during processing, the treatment time was shortened to 120 s. Under this condition, the degradation efficiency of malathion (0.5 mg kg-1 ) and chlorpyrifos (1.0 mg kg-1 ) on lettuces was found to be 53.1% and 51.4%. More importantly, we noted that cold plasma treatment significantly inactivated the microorganisms on lettuces. CONCLUSION: The results of the present study show that cold plasma is an effective and safe method for the degradation of organic pesticide residues on fresh vegetables at the same time as retaining the original quality. © 2020 Society of Chemical Industry.


Asunto(s)
Cloropirifos/química , Contaminación de Alimentos/prevención & control , Manipulación de Alimentos/métodos , Lechuga/efectos de los fármacos , Malatión/química , Residuos de Plaguicidas/química , Hojas de la Planta/química , Gases em Plasma/farmacología , Contaminación de Alimentos/análisis , Manipulación de Alimentos/instrumentación , Cinética , Lechuga/química , Hojas de la Planta/efectos de la radiación , Contaminantes Químicos del Agua/química
18.
Food Chem ; 337: 127783, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32791427

RESUMEN

Jujube slices were pretreated by cold plasma for 15, 30, and 60 s on each side, followed by hot air drying at 50, 60, and 70 °C. Scanning electron microscopy investigation indicated that the application of cold plasma significantly changed the surface topography of jujube slice by etching larger cavities, which can facilitate moisture transfer and consequently enhance drying rate and effective diffusivity. Modified Henderson & Pabis model and Two-term model were the two most recommended models for describing the drying kinetics of jujube slices. Cold plasma pretreatment improved the contents of procyanidins, flavonoids, and phenolics by 53.81%, 33.89%, and 13.85% at most, respectively, and thereby enhanced antioxidant capacity by 36.85% at most. Besides, cold plasma pretreatment can reduce the production of 5-hydroxymethylfurfural by 52.19% at most. In summary, cold plasma can be used as a promising pretreatment tool for drying processes of jujube slices.


Asunto(s)
Desecación/métodos , Manipulación de Alimentos/métodos , Frutas/química , Gases em Plasma , Ziziphus/química , Antioxidantes/análisis , Flavonoides/análisis , Cinética , Fenoles/análisis , Proantocianidinas/análisis
19.
Chemosphere ; 263: 127893, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32835971

RESUMEN

Toluene and styrene were two typical aromatic VOCs which were commonly used and coexistence in the exhaust gases from industrial manufacturing. Their simultaneous removal performances under non-thermal plasma (NTP) and NTP-catalysis were carried out and compared by a single stage coaxial dielectric barrier discharge (DBD) reactor. The effects of VOCs mixture, humidity, materials filling in the discharge zoon on the removal efficiency, COx selectivity, byproducts types and their emission levels were deeply investigated to explore the degradation mechanism and coexistence effect. Experimental results showed that the toluene removal was significantly inhibited when treated together with styrene under plasma treatment. But that of styrene was hardly affected at the same conditions. It was found that benzaldehyde as the primary organic byproducts from styrene consumed the oxidizing particles (O and . OH), limiting the conversion of toluene. The introduction of Cu-doped MnO2 materials significantly improved the VOCs removal performance with nearly 100% conversion to COx at a discharge power less than 30 W, as well as O3 generation from more than 1.2 mg L-1 by NTP to 1.6 × 10-3 mg L-1 by NTP-catalysis. With the help of in situ FT-IR, it was believed that catalysts not only accelerated the adsorption and degradation of pollutants but also utilized ozone to involve this process. At last, a plausible explanation on binary coexistence effect under different conditions had been suggested and discussed.


Asunto(s)
Tolueno/química , Compuestos Orgánicos Volátiles/química , Adsorción , Catálisis , Compuestos de Manganeso , Óxidos , Ozono , Gases em Plasma , Espectroscopía Infrarroja por Transformada de Fourier , Estireno
20.
Water Res ; 188: 116513, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33091801

RESUMEN

Although the identification of effective reactive oxygen species (ROS) generated by plasma has been extensively studied, yet the subcellular mechanism of microbial inactivation has never been clearly elucidated in plasma disinfection processes. In this study, subcellular mechanism of yeast cell inactivation during plasma-liquid interaction was revealed in terms of comprehensive factors including cell morphology, membrane permeability, lipid peroxidation, membrane potential, intracellular redox homeostasis (intracellular ROS and H2O2, and antioxidant system (SOD, CAT and GSH)), intracellular ionic equilibrium (intracellular H+ and K+) and energy metabolism (mitochondrial membrane potential, intracellular Ca2+ and ATP level). The ROS analysis show that ·OH, 1O2, ·O2-and H2O2 were generated in this plasma-liquid interaction system and ·O2-served as the precursor of 1O2. Additionally, the solution pH was reduced. Plasma can effectively inactivate yeast cells mainly via apoptosis by damaging cell membrane, intracellular redox and ion homeostasis and energy metabolism as well as causing DNA fragmentation. ROS scavengers (l-His, d-Man and SOD) and pH buffer (phosphate buffer solution, PBS) were employed to investigate the role of five antimicrobial factors (·OH, 1O2, ·O2-, H2O2 and low pH) in plasma sterilization. Results show that they have different influences on the aforementioned cell physiological activities. The ·OH and 1O2 contributed most to the yeast inactivation. The ·OH mainly attacked cell membrane and increased cell membrane permeability. The disturb of cell energy metabolism was mainly attributed to 1O2. The damage of cell membrane as well as extracellular low pH could break the intracellular ionic equilibrium and further reduce cell membrane potential. The remarkable increase of intracellular H2O2 was mainly due to the influx of extracellular H2O2 via destroyed cell membrane, which played a little role in yeast inactivation during 10-min plasma treatment. These findings provide comprehensive insights into the antimicrobial mechanism of plasma, which can promote the development of plasma as an alternative water disinfection strategy.


Asunto(s)
Gases em Plasma , Desinfección , Humanos , Peróxido de Hidrógeno , Viabilidad Microbiana , Plasma , Presión , Especies Reactivas de Oxígeno , Agua
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