Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 549
Filtrar
1.
Int J Food Microbiol ; 337: 108948, 2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33197682

RESUMO

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.


Assuntos
Antibacterianos/farmacologia , Manipulação de Alimentos/métodos , Listeria/efeitos dos fármacos , Nisina/farmacologia , Gases em Plasma/farmacologia , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Listeria/crescimento & desenvolvimento , Modelos Biológicos , Pasteurização/métodos
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.
PLoS One ; 15(12): e0243965, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33326504

RESUMO

The response to the COVID-19 epidemic is generating severe shortages of personal protective equipment around the world. In particular, the supply of N95 respirator masks has become severely depleted, with supplies having to be rationed and health care workers having to use masks for prolonged periods in many countries. We sought to test the ability of 7 different decontamination methods: autoclave treatment, ethylene oxide gassing (ETO), low temperature hydrogen peroxide gas plasma (LT-HPGP) treatment, vaporous hydrogen peroxide (VHP) exposure, peracetic acid dry fogging (PAF), ultraviolet C irradiation (UVCI) and moist heat (MH) treatment to decontaminate a variety of different N95 masks following experimental contamination with SARS-CoV-2 or vesicular stomatitis virus as a surrogate. In addition, we sought to determine whether masks would tolerate repeated cycles of decontamination while maintaining structural and functional integrity. All methods except for UVCI were effective in total elimination of viable virus from treated masks. We found that all respirator masks tolerated at least one cycle of all treatment modalities without structural or functional deterioration as assessed by fit testing; filtration efficiency testing results were mostly similar except that a single cycle of LT-HPGP was associated with failures in 3 of 6 masks assessed. VHP, PAF, UVCI, and MH were associated with preserved mask integrity to a minimum of 10 cycles by both fit and filtration testing. A similar result was shown with ethylene oxide gassing to the maximum 3 cycles tested. Pleated, layered non-woven fabric N95 masks retained integrity in fit testing for at least 10 cycles of autoclaving but the molded N95 masks failed after 1 cycle; filtration testing however was intact to 5 cycles for all masks. The successful application of autoclaving for layered, pleated masks may be of particular use to institutions globally due to the virtually universal accessibility of autoclaves in health care settings. Given the ability to modify widely available heating cabinets on hospital wards in well-resourced settings, the application of moist heat may allow local processing of N95 masks.


Assuntos
Descontaminação/métodos , Reutilização de Equipamento , /virologia , /patologia , Óxido de Etileno/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia , Ácido Peracético/farmacologia , Gases em Plasma/farmacologia , /isolamento & purificação , Raios Ultravioleta , Vesiculovirus/efeitos dos fármacos , Vesiculovirus/efeitos da radiação
4.
Int J Food Microbiol ; 335: 108889, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33007604

RESUMO

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


Assuntos
Anti-Infecciosos/farmacologia , Resistência Microbiana a Medicamentos , Microbiota/efeitos dos fármacos , Gases em Plasma/farmacologia , Triticum/microbiologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Grão Comestível/microbiologia , Fungos/classificação , Fungos/efeitos dos fármacos , Fungos/genética , Fungos/isolamento & purificação , RNA Ribossômico/genética , Especificidade da Espécie
5.
Anticancer Res ; 40(11): 6205-6212, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33109557

RESUMO

BACKGROUND/AIM: Mammary carcinoma (MC) remains one of the leading causes of morbidity and mortality in the female population worldwide. Cold physical plasma at atmospheric pressure (CAP) has an antioncogenic effect on tumor cells, and its anticancer properties may complement or even extend existing treatment options. In the present study, the efficacy of CAP was characterized on an MC in vitro cell culture system. MATERIALS AND METHODS: MC cells (MCF-7, MDA-MB-231) were directly treated with CAP or incubated with CAP-treated cell culture medium. Cell growth, cell mobility and apoptosis were subsequently analyzed. RESULTS: A single treatment of MC cells with CAP and CAP treated medium led to a treatment-time dependent reduction of cell growth. Furthermore, CAP exposure led to a loss of cellular motility and induced apoptosis. CONCLUSION: Due to its anticancer properties, CAP treatment is an innovative and promising physical approach to expand and complement the treatment options for MC. In particular, a combination of CAP application with surgical and/or chemotherapeutic interventions might significantly improve the therapeutic outcomes.


Assuntos
Argônio/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Gases em Plasma/uso terapêutico , Argônio/farmacologia , Pressão Atmosférica , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Cinética , Gases em Plasma/farmacologia
6.
Int J Food Microbiol ; 335: 108892, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-32979616

RESUMO

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


Assuntos
Argônio/farmacologia , Descontaminação/métodos , Qualidade dos Alimentos , Gases em Plasma/farmacologia , Prunus dulcis/microbiologia , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Humanos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
7.
Int J Nanomedicine ; 15: 5813-5824, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821103

RESUMO

Introduction: This paper presents a novel technique for the synthesis of graphene oxide (GO) with various surface features using high-density atmospheric plasma deposition. Furthermore, to investigate the use of hydrophobic, super-hydrophobic, and hydrophilic graphene in biological applications, we synthesized hydrophobic, super-hydrophobic, and hydrophilic graphene oxides by additional heat treatment and argon plasma treatment, respectively. In contrast to conventional fabrication procedures, reduced graphene oxide (rGO) formed under low pressure and high-temperature environment using a new synthesis method-developed and described in this study-offers a convenient deposition method on any kind surface with controlled wettability. Methods: High density at atmospheric plasma is used for the synthesis of rGO and GO and its biocompatibility based on various wetting properties was evaluated using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, and the viability of cells in response to rGO and GO with various surface features was investigated. Structural integrity was characterized by Raman spectroscopy, FESEM and FE-TEM. Wettability was measured via contact angle method and confirmed with XPS analysis. Results: We found that GO coating with a hydrophilic feature is more biocompatible than other surfaces as observed in case of fibroblast cells. We have shown that wettability-controlled by GO deposition-influences biocompatibilities and antibacterial effect of biomaterial surfaces. Discussion: Measuring the contact angle, it is found that contact angle for hydrophobic is increased to 150.590 and reduced to 11.580 by heat and argon plasma treatment, respectively, from 75.880 that was initially in the case of hydrophobic surface. XPS analysis confirmed various oxygen-containing functional groups transforming as deposited hydrophobic surface into superhydrophobic and hydrophilic surface. Thus, we have proposed a new, direct, cost-effective, and highly productive method for the synthesis of rGO and GO-with various surface properties-for biological applications. Similarly, for the dental implant application, the Streptococcus mutans was used as an antibacterial effect and found that S. mutans grows slowly on hydrophilic surface. Thus, antibacterial effect was prominent on GO with hydrophilic surface.


Assuntos
Atmosfera/química , Grafite/síntese química , Gases em Plasma/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Grafite/química , Camundongos , Viabilidade Microbiana/efeitos dos fármacos , Oxirredução , Streptococcus mutans/efeitos dos fármacos , Água , Molhabilidade
8.
Anticancer Res ; 40(7): 3743-3749, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32620613

RESUMO

BACKGROUND/AIM: The antiproliferative effects of cold atmospheric plasma (CAP) make it a promising application option in oncology. The aim of the present study was to examine whether short-term CAP treatment leads to an initial partial elimination of the treated cells or to long-term impairement and inhibition of cell growth. MATERIALS AND METHODS: Cells were treated with CAP and biostatistical modelling was used to estimate growth rates over the incubation time. Four cell lines (U2-OS and MNNG osteosarcoma cells, 3T3 fibroblasts, HaCaT keratinocytes) and three CAP sources (MiniJet-R, kINPen MED, Maxium) were used. RESULTS: The antiproliferative efficacy of CAP was due to a significant reduction in cell count during treatment and the long-lasting inhibition of growth rate in the remaining cells, detectable in all cell lines and after treatment using all three CAP devices. CONCLUSION: Induction of cell death and inhibition of cell growth are part of a general mechanism of biological CAP efficacy. However, data contradict the hypothesis that cancer cells respond more sensitively to CAP treatment compared to non-malignant cells.


Assuntos
Proliferação de Células/efeitos dos fármacos , Plasmócitos/patologia , Gases em Plasma/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Cinética , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Plasmócitos/efeitos dos fármacos
9.
Arch Oral Biol ; 117: 104822, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32592931

RESUMO

OBJECTIVE: Overcoming substantial shortcomings of soft liners as physico-chemical changes and liner-biofilm-related infections remains a challenge in the rehabilitation treatment. In this study, protective non-thermal plasma (NTP) treatments were developed on the soft liner surface to improve its surface and physico-chemical properties and to reduce fungal colonization after biofilm inhibition challenge. METHODS: Resinous liner specimens (Coe-Soft) were prepared and distributed in 3 groups according to the surface treatments: (1) untreated (control); (2) treated with sulfur hexafluoride-based NTP (SF6); and (3) treated with hexamethyldisiloxane-based NTP (HMDSO). To test the NTP stability and their protective and antimicrobial effect on the liner surface over time, the morphology, chemical composition, roughness, water contact angle, shore A hardness, sorption and solubility were evaluated before and after the specimens were exposed to dual-species biofilm of Candida albicans and Streptococcus oralis for 14 days. Colony forming units and biofilm structure were assessed. Data were submitted to ANOVA and Tukey tests (α = 0.05). RESULTS: Both treatments modified the surface morphology, increased hydrophobicity and roughness of the liner, and were effective to reduce C. albicans adhesion without affecting the commensal health-associated S. oralis. HMDSO presented chemical stability and lower hardness in both periods, whereas SF6 exhibited higher initial hardness than control and the highest sorption; contrarily, similar solubility was noted for all groups. CONCLUSION: HMDSO-based film showed improved physico-chemical properties and inhibited C. albicans biofilm. Thus, it has potential for use to control candida-related stomatitis and improve liner's stability even after being exposed to biofilm inhibition challenge.


Assuntos
Anti-Infecciosos , Biofilmes , Reembasadores de Dentadura , Gases em Plasma , Anti-Infecciosos/farmacologia , Candida albicans , Teste de Materiais , Gases em Plasma/farmacologia , Streptococcus oralis , Propriedades de Superfície
10.
Arch Biochem Biophys ; 689: 108462, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32590068

RESUMO

Silver nanoparticles (AgNP) emerged as a promising reagent for cancer therapy with oxidative stress implicated in the toxicity. Meanwhile, studies reported cold atmospheric plasma (CAP) generation of reactive oxygen and nitrogen species has selectivity towards cancer cells. Gold nanoparticles display synergistic cytotoxicity when combined with CAP against cancer cells but there is a paucity of information using AgNP, prompting to investigate the combined effects of CAP using dielectric barrier discharge system (voltage of 75 kV, current is 62.5 mA, duty cycle of 7.5kVA and input frequency of 50-60Hz) and 10 nm PVA-coated AgNP using U373MG Glioblastoma Multiforme cells. Cytotoxicity in U373MG cells was >100-fold greater when treated with both CAP and PVA-AgNP compared with either therapy alone (IC50 of 4.30 µg/mL with PVA-AgNP alone compared with 0.07 µg/mL after 25s CAP and 0.01 µg/mL 40s CAP). Combined cytotoxicity was ROS-dependent and was prevented using N-Acetyl Cysteine. A novel darkfield spectral imaging method investigated and quantified AgNP uptake in cells determining significantly enhanced uptake, aggregation and subcellular accumulation following CAP treatment, which was confirmed and quantified using atomic absorption spectroscopy. The results indicate that CAP decreases nanoparticle size, decreases surface charge distribution of AgNP and induces uptake, aggregation and enhanced cytotoxicity in vitro.


Assuntos
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Gases em Plasma/farmacologia , Prata/farmacologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Nanopartículas Metálicas/análise , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Prata/farmacocinética
11.
Trends Biotechnol ; 38(11): 1278-1291, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32418663

RESUMO

Viruses can infect all cell-based organisms, from bacteria to humans, animals, and plants. They are responsible for numerous cases of hospitalization, many deaths, and widespread crop destruction, all of which result in an enormous medical, economical, and biological burden. Each of the currently used decontamination methods has important drawbacks. Cold plasma (CP) has entered this field as a novel, efficient, and clean solution for virus inactivation. We present recent developments in this promising field of CP-mediated virus inactivation, and describe the applications and mechanisms of the inactivation. This is particularly relevant because viral pandemics, such as COVID-19, highlight the need for alternative virus inactivation methods to replace, complement, or upgrade existing procedures.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Gases em Plasma/farmacologia , Pneumonia Viral/prevenção & controle , Inativação de Vírus , Animais , Bacteriófagos/patogenicidade , Betacoronavirus/patogenicidade , Biotecnologia/instrumentação , Infecções por Coronavirus/transmissão , Descontaminação/métodos , Desinfecção/métodos , Microbiologia Ambiental , Humanos , Modelos Biológicos , Vírus de Plantas/patogenicidade , Gases em Plasma/química , Pneumonia Viral/transmissão , Estudo de Prova de Conceito , Vírus/patogenicidade
12.
Anticancer Res ; 40(5): 2591-2599, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32366404

RESUMO

BACKGROUND: Physical plasma is a mixture of reactive particles and electromagnetic radiation. Due to the antimicrobial, immunomodulatory, anti-inflammatory, wound-healing promoting, and antineoplastic effects of body tempered physical plasma under atmospheric pressure (cold atmospheric plasma: CAP), CAP therapy is increasingly becoming the focus of surgical and oncological disciplines. However, when applied in practice, a potential emission of harmful noxae such as toxic nitrogen oxides must be taken into account, which was investigated in the following study. MATERIALS AND METHODS: MiniJet-R Ar CAP device was characterized with respect to NOX-specific spectra, ultraviolet radiation C (UVC) intensity in the range of 200-275 nm and the formation of NOX gases. Instrument-specific parameters such as gas flow, energy setting of the high-frequency generator, and flow rate of the carrier gas Ar were varied. To test the toxic properties of the NO2 concentrations formed by CAP, SK-OV-3 human ovarian cancer cells were incubated with different NO2 concentrations and cell growth was monitored for 120 h. RESULTS: The operation of MiniJet-R led to the formation of NO2 in the proximity of the CAP effluent. Synthesis of NO led to a NO-specific spectrum in the range of 100-275 nm, whereby UVC radiation produced reached intensities of up to 90 mW/m2 NO gas itself, however, was not detectable, as it was converted to NO2 rapidly. Cell culture incubation experiments demonstrated that NO2 in these concentration ranges had no influence on the cell growth of human cancer cells. CONCLUSION: Although no limit values were exceeded in the present study, the emission of high-energy UVC radiation and toxic NO2 is a risk factor with regard to the legal regulations on workplace protection (operator hazard) and the approval of medical devices (patient hazard). This is important for considerations regarding treatment frequency and duration. The growth inhibitory effect of CAP treatment on human cancer cells principally suggests a medical application of the MiniJet-R device, although more extensive studies will have to follow.


Assuntos
Pressão Atmosférica , Dióxido de Nitrogênio/toxicidade , Gases em Plasma/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Óxido Nítrico/análise , Dióxido de Nitrogênio/análise , Raios Ultravioleta
13.
PLoS One ; 15(5): e0232724, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32374749

RESUMO

DNA damage in the A549 human lung cancer cell line treated with cold plasma irradiation was investigated. We confirmed that cold atmospheric plasma generated reactive oxygen and nitrogen species (RONS) in a liquid, and the intracellular RONS level was increased in plasma-irradiated cells. However, a notable decrease in cell viability was not observed 24 hours after plasma irradiation. Because RONS induce oxidative damage in cells, strand breaks and chemical modification of DNA in the cancer cells were investigated. We found that 8-oxoguanine (8-oxoG) formation as well as DNA strand breaks, which have been thoroughly investigated, were induced by plasma irradiation. In addition, up-regulation of 8-oxoG repair enzyme was observed after plasma irradiation.


Assuntos
Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Quebras de DNA de Cadeia Simples/efeitos dos fármacos , DNA Glicosilases/metabolismo , Reparo do DNA , Guanina/análogos & derivados , Gases em Plasma/farmacologia , Células A549 , Sobrevivência Celular/efeitos dos fármacos , DNA/metabolismo , Guanina/biossíntese , Humanos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima
14.
J Food Prot ; 83(5): 794-800, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32318724

RESUMO

ABSTRACT: Cilantro was recently identified as a vehicle for protozoan illness. Current postharvest practices are not sufficient to inactivate protozoa on cilantro. Cold plasma is an emerging nonthermal waterless technology with potential applications in food processing that are currently being investigated to enhance the safety of herbs. The purpose of this study was to determine the impact of cold atmospheric plasma (CP) on the viability of Cryptosporidium parvum oocysts on cilantro. C. parvum oocysts were inoculated onto cilantro and treated with a CP jet for 0, 30, 90, and 180 s at a working distance of 10 cm with a flow of 1.42 × 10-3 m3/s. Oocyst viability was determined using HCT-8 cell culture infectivity assays. Overall, each treatment significantly reduced oocyst infectivity compared with the 0-s treatment control (P ≤ 0.02). Log inactivations of oocysts observed on cilantro were 0.84, 1.23, and 2.03 for the 30-, 90-, and 180-s treatment times, respectively. Drying and darkening of cilantro leaves was observed with treatments longer than 30 s. CP can reduce C. parvum infectivity on cilantro. With further research and optimization, this treatment technology has potential applications in postharvest processing of cilantro.


Assuntos
Coriandrum , Cryptosporidium parvum , Gases em Plasma , Animais , Coriandrum/parasitologia , Criptosporidiose/prevenção & controle , Cryptosporidium , Cryptosporidium parvum/efeitos dos fármacos , Cryptosporidium parvum/crescimento & desenvolvimento , Manipulação de Alimentos , Parasitologia de Alimentos , Oocistos , Gases em Plasma/farmacologia
15.
J Biosci Bioeng ; 130(1): 48-53, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32224010

RESUMO

Macrolactins (MLNs) have attracted considerable attention due to their antibacterial and antiviral properties. Here, the MLN production of Bacillus sp. strain IMDGX0108 was improved using a breeding strategy of atmospheric room temperature plasma (ARTP) technique. Combining with a selection procedure based on the colony morphology and specific growth rate index (SGRI), two genetically stable mutants A29 and A72 were identified. The MLN production of A29 and A72 was 35.2% and 52.8% greater than that of the parent strain, respectively. The best-performing mutant A72 was subjected to RNA-sequence analysis. Five pathways were significantly enriched, and fatty acid bioprocesses might play an important role in improving the production of MLNs. The combined strategy developed herein (i.e., ARTP mutation plus an efficient screening procedure) might be an appropriate method by which to obtain strains overproducing MLNs.


Assuntos
Bacillus/efeitos dos fármacos , Bacillus/crescimento & desenvolvimento , Alcaloides Indólicos/metabolismo , Gases em Plasma/farmacologia , Bacillus/química , Bacillus/genética , Ácidos Graxos/metabolismo , Cinética , Mutação
16.
J Food Sci ; 85(4): 1203-1212, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32118300

RESUMO

Listeria monocytogenes is often responsible for postprocessing contamination of ready-to-eat (RTE) products including cooked ham. As an emerging technology, atmospheric cold plasma (ACP) has the potential to inactivate L. monocytogenes in packaged RTE meats. The objectives of this study were to evaluate the effect of treatment time, modified atmosphere gas compositions (MAP), ham formulation, and post-treatment storage (1 and 7 days at 4 °C) on the reduction of a five-strain cocktail of L. monocytogenes and quality changes in ham subjected to in-package ACP treatment. Initial average cells population on ham surfaces were 8 log CFU/cm2 . The ACP treatment time and gas composition significantly (P < 0.05) influenced the inactivation of L. monocytogenes, irrespective of ham formulations. When MAP1 (20% O2 + 40% CO2 + 40% N2 ) was used, there was a significantly higher log reduction (>2 log reduction) in L. monocytogenes on ham in comparison to MAP2 (50% CO2 + 50% N2 ) and MAP3 (100% CO2 ), irrespective of ham formulation. Addition of preservatives (that is, 0.1% sodium diacetate and 1.4% sodium lactate) or bacteriocins (that is, 0.05% of a partially purified culture ferment from Carnobacterium maltaromaticum UAL 307) did not significantly reduce cell counts of L. monocytogenes after ACP treatment. Regardless of type of ham, storage of 24 hr after ACP treatment significantly reduced cells counts of L. monocytogenes to approximately 4 log CFU/cm2 . Following 7 days of storage after ACP treatment, L. monocytogenes counts were below the detection limit (>6 log reduction) when samples were stored in MAP1. However, there were significant changes in lipid oxidation and color after post-treatment storage. In conclusion, the antimicrobial efficacy of ACP is strongly influenced by gas composition inside the package and post-treatment storage. PRACTICAL APPLICATION: Surface contamination of RTE ham with L. monocytogenes may occur during processing steps such as slicing and packaging. In-package ACP is an emerging nonthermal technology, which can be used as a postpackaging decontamination step in industrial settings. This study demonstrated the influence of in-package gas composition, treatment time, post-treatment storage, and ham formulation on L. monocytogenes inactivation efficacy of ACP. Results of present study will be helpful to optimize in-package ACP treatment and storage conditions to reduce L. monocytogenes, while maintaining the quality of ham.


Assuntos
Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Produtos da Carne/microbiologia , Gases em Plasma/farmacologia , Animais , Bacteriocinas/farmacologia , Contagem de Colônia Microbiana , Contaminação de Alimentos/análise , Embalagem de Alimentos/instrumentação , Conservação de Alimentos/instrumentação , Conservantes de Alimentos/farmacologia , Armazenamento de Alimentos , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Produtos da Carne/análise , Lactato de Sódio/farmacologia , Suínos
17.
Sci Rep ; 10(1): 3673, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32111863

RESUMO

Fungal diseases seriously affect agricultural production and the food industry. Crop protection is usually achieved by synthetic fungicides, therefore more sustainable and innovative technologies are increasingly required. The atmospheric pressure low-temperature plasma is a novel suitable measure. We report on the effect of plasma treatment on phytopathogenic fungi causing quantitative and qualitative losses of products both in the field and postharvest. We focus our attention on the in vitro direct inhibitory effect of non-contact Surface Dielectric Barrier Discharge on conidia germination of Botrytis cinerea, Monilinia fructicola, Aspergillus carbonarius and Alternaria alternata. A few minutes of treatment was required to completely inactivate the fungi on an artificial medium. Morphological analysis of spores by Scanning Electron Microscopy suggests that the main mechanism is plasma etching due to Reactive Oxygen Species or UV radiation. Spectroscopic analysis of plasma generated in humid air gives the hint that the rotational temperature of gas should not play a relevant role being very close to room temperature. In vivo experiments on artificially inoculated cherry fruits demonstrated that inactivation of fungal spores by the direct inhibitory effect of plasma extend their shelf life. Pre-treatment of fruits before inoculation improve the resistance to infections maybe by activating defense responses in plant tissues.


Assuntos
Fungos Mitospóricos/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Gases em Plasma , Esporos Fúngicos/crescimento & desenvolvimento , Gases em Plasma/química , Gases em Plasma/farmacologia
18.
Sci Rep ; 10(1): 4917, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188896

RESUMO

Soybean (Glycine max (L.) Merrill) is one of the most important crops worldwide providing dietary protein and vegetable oil. Most of the nitrogen required by the crop is supplied through biological N2 fixation. Non-thermal plasma is a fast, economical, and environmental-friendly technology that can improve seed quality, plant growth, and crop yield. Soybean seeds were exposed to a dielectric barrier discharge plasma operating at atmospheric pressure air with superimposed flows of O2 or N2 as carrying gases. An arrangement of a thin phenolic sheet covered by polyester films was employed as an insulating barrier. We focused on the ability of plasma to improve soybean nodulation and biological nitrogen fixation. The total number of nodules and their weight were significantly higher in plants grown from treated seeds than in control. Plasma treatments incremented 1.6 fold the nitrogenase activity in nodules, while leghaemoglobin content was increased two times, indicating that nodules were fixing nitrogen more actively than control. Accordingly, the nitrogen content in nodules and the aerial part of plants increased by 64% and 23%, respectively. Our results were supported by biometrical parameters. The results suggested that different mechanisms are involved in soybean nodulation improvement. Therefore, the root contents of isoflavonoids, glutathione, auxin and cytokinin, and expansin (GmEXP1) gene expression were determined. We consider this emerging technology is a suitable pre-sowing seed treatment.


Assuntos
Fixação de Nitrogênio , Nodulação , Gases em Plasma , Nódulos Radiculares de Plantas/fisiologia , Sementes , Soja/fisiologia , Nitrogênio/metabolismo , Fixação de Nitrogênio/efeitos dos fármacos , Fenótipo , Desenvolvimento Vegetal , Nodulação/efeitos dos fármacos , Gases em Plasma/farmacologia , Característica Quantitativa Herdável , Nódulos Radiculares de Plantas/efeitos dos fármacos , Sementes/efeitos dos fármacos , Soja/efeitos dos fármacos
19.
Int J Mol Sci ; 21(6)2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32178401

RESUMO

BACKGROUND: Autophagy is reported as a survival or death-promoting pathway that is highly debatable in different kinds of cancer. Here, we examined the co-effect of cold atmospheric plasma (CAP) and silymarin nanoemulsion (SN) treatment on G-361 human melanoma cells via autophagy induction. METHODS: The temperature and pH of the media, along with the cell number, were evaluated. The intracellular glucose level and PI3K/mTOR and EGFR downstream pathways were assessed. Autophagy-related genes, related transcriptional factors, and autophagy induction were estimated using confocal microscopy, flow cytometry, and ELISA. RESULTS: CAP treatment increased the temperature and pH of the media, while its combination with SN resulted in a decrease in intracellular ATP with the downregulation of PI3K/AKT/mTOR survival and RAS/MEK transcriptional pathways. Co-treatment blocked downstream paths of survival pathways and reduced PI3K (2 times), mTOR (10 times), EGFR (5 times), HRAS (5 times), and MEK (10 times). CAP and SN co-treated treatment modulates transcriptional factor expressions (ZKSCAN3, TFEB, FOXO1, CRTC2, and CREBBP) and specific genes (BECN-1, AMBRA-1, MAP1LC3A, and SQSTM) related to autophagy induction. CONCLUSION: CAP and SN together activate autophagy in G-361 cells by activating PI3K/mTOR and EGFR pathways, expressing autophagy-related transcription factors and genes.


Assuntos
Autofagia/efeitos dos fármacos , Emulsões/farmacologia , Melanoma/tratamento farmacológico , Nanopartículas/administração & dosagem , Gases em Plasma/farmacologia , Silimarina/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos
20.
Anticancer Res ; 40(2): 841-846, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32014927

RESUMO

BACKGROUND: Cold atmospheric plasma (CAP) has a variety of anticancer effects on different cancer cell types. In osteosarcoma (OS) cells, CAP reduces growth and motility, induces apoptosis, and alters secretion of cellular factors. The influence of CAP on membrane integrity of OS cells is unknown. MATERIALS AND METHODS: Two different OS cell lines (U-2 OS and MNNG-HOS) were treated with CAP. Proliferation assays for cell growth after treatment was performed. Alterations in membrane permeability and the associated translocation of low molecular weight particles through the cytoplasmic membrane of OS cells after CAP treatment were shown in fluorescein diacetate (FDA) assays. RESULTS: FDA increasingly passed the membrane after CAP treatment and this effect depended on the duration of treatment. It was also shown that after CAP treatment, FDA was able to diffuse into the cells from the outside as well as out of the cell interior. These effects were observed when CAP-treated buffer was used and therefore no direct contact between cells and CAP occurred. CONCLUSION: The observations suggest that changes in membrane permeability and function may contribute to the antiproliferative effects of CAP.


Assuntos
Permeabilidade da Membrana Celular/efeitos dos fármacos , Osteossarcoma/tratamento farmacológico , Gases em Plasma/uso terapêutico , Linhagem Celular Tumoral , Humanos , Osteossarcoma/patologia , Gases em Plasma/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA