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1.
Waste Manag ; 186: 11-22, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38843559

RESUMO

The fast development of the waste incineration industry requires deeper insights into heating surface corrosion behavior at higher operating parameters with complex corrosion sources. This research investigates the corrosion behaviors of three types of plates, namely SA210-C, TP310, and 12CrMoV, when subjected to simulated flue gas and fly ash deposition simultaneously at temperatures ranging from 500℃ to 620℃. The results indicate that the weight loss due to coupling corrosion was 2.5 to 84.5 times higher than that of gas-phase corrosion under the same operating conditions. Among the three stainless-steels, TP310 demonstrates superior corrosion resistance. It is worth noting that, under the gas-solid coupling corrosion conditions, we observed a distinct two-layer structure of corrosion products. Despite the fly ash simulants detaching over time, the two-layer structure remained unchanged. Based on the theory of eutectic molten salt formation, we propose that alkali metal chlorides only initiate the formation of the molten layer in the initial stage of corrosion. Furthermore, we offer additional suggestions for the mechanism of sustaining the molten layer in the absence of alkali metal chlorides.


Assuntos
Cloro , Cinza de Carvão , Incineração , Aço Inoxidável , Incineração/métodos , Corrosão , Cinza de Carvão/química , Cloro/química , Aço Inoxidável/química , Vapor/análise , Gases/química
2.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36142238

RESUMO

Plants produce a variety of high-value chemicals (e.g., secondary metabolites) which have a plethora of biological activities, which may be utilised in many facets of industry (e.g., agrisciences, cosmetics, drugs, neutraceuticals, household products, etc.). Exposure to various different environments, as well as their treatment (e.g., exposure to chemicals), can influence the chemical makeup of these plants and, in turn, which chemicals will be prevalent within them. Essential oils (EOs) usually have complex compositions (>300 organic compounds, e.g., alkaloids, flavonoids, phenolic acids, saponins and terpenes) and are obtained from botanically defined plant raw materials by dry/steam distillation or a suitable mechanical process (without heating). In certain cases, an antioxidant may be added to the EO (EOs are produced by more than 17,500 species of plants, but only ca. 250 EOs are commercially available). The interesting bioactivity of the chemicals produced by plants renders them high in value, motivating investment in their production, extraction and analysis. Traditional methods for effectively extracting plant-derived biomolecules include cold pressing and hydro/steam distillation; newer methods include solvent/Soxhlet extractions and sustainable processes that reduce waste, decrease processing times and deliver competitive yields, examples of which include microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), subcritical water extraction (SWE) and supercritical CO2 extraction (scCO2). Once extracted, analytical techniques such as chromatography and mass spectrometry may be used to analyse the contents of the high-value extracts within a given feedstock. The bioactive components, which can be used in a variety of formulations and products (e.g., displaying anti-aging, antibacterial, anticancer, anti-depressive, antifungal, anti-inflammatory, antioxidant, antiparasitic, antiviral and anti-stress properties), are biorenewable high-value chemicals.


Assuntos
Óleos Voláteis , Saponinas , Antibacterianos/química , Antifúngicos/análise , Antioxidantes/química , Antiparasitários , Antivirais/análise , Dióxido de Carbono/química , Flavonoides , Óleos Voláteis/química , Extratos Vegetais/química , Plantas , Solventes/química , Vapor/análise , Terpenos
3.
Chemosphere ; 308(Pt 1): 136182, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36037942

RESUMO

Volatile organic compounds (VOCs) are a group of organic compounds that have a molecular structure containing carbon and their chemical properties allow them to be easily converted to steam and gas and remain for a long period of time and have diverse effects on the environment. The purpose of this study is determination of the concentration of VOCs such as alachlor, anthracene, benzene, bromoform, chloroform, heptachlor, isophorone, tetrachloroethylene, γ -chlordane, toluene, etc. in water matrices. The results showed that among studies conducted on VOCs, the concentration of tetrachloroethylene, m,p-xylene, and toluene were at the top in water matrices, and the lowest average concentrations were found in chloroform, anthracene, and butyl benzyl phthalate. In terms of VOC concentrations in water matrices, China was the most polluted country. Moreover, the data analysis indicated that China was the only country with carcinogenic risk. A Monte-Carlo simulation showed that although the averages obtained were comparable to the acceptable limits, for heptachlor, the maximum carcinogenic risk is achieved at a level that is slightly over the limit, only 25% from the population being exposed.


Assuntos
Poluentes Atmosféricos , Tetracloroetileno , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Antracenos/análise , Benzeno/análise , Carbono/análise , China , Clordano/análise , Clorofórmio/análise , Monitoramento Ambiental/métodos , Heptacloro/análise , Vapor/análise , Tetracloroetileno/análise , Tolueno/análise , Compostos Orgânicos Voláteis/análise , Água/análise
4.
Int J Biol Macromol ; 216: 927-939, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35917854

RESUMO

In this study, nanocomposites of polylactic acid (PLA) with clove essential oil (CEO) and alkali treated halloysite nanotubes (NHNT) as fillers were synthesized by using simple solvent casting method. The treatment of halloysite nanotubes with NaOH increased the surface area from 50.16 m2⋅g-1 to 57.01 m2⋅g-1 and pore volume from 0.25 cm3⋅g-1 to 0.32 cm3⋅g-1. The as-synthesized nanocomposite films were characterized for physical, thermal, mechanical and water vapor barrier properties towards their use as food packaging material. The nanocomposite film PCOH0.5 (consisting 0.5 wt% NHNT and 200 µL CEO) possessed the best physical properties with percentage enhancements over PLA as: surface hydrophobicity (20.2 %), water vapor barrier (42.1 %), thermal stability (3.2 %), flexibility (682 %), tensile strength (20 %), elastic modulus (38 %), UV barrier property (62 %). In addition, a practical packaging test was performed on cut apples stored at room temperature for 6 days. The PCOH0.5 films showed substantially improved results (as compared to PLA) as follows: weight loss (40.5 %), mesophilic count (4.0 %), firmness (116.6 %), titratable acidity (110.8 %), pH (2.9 %) and total soluble solids (8.9 %). The results clearly indicate the efficiency of PLA/CEO/NHNT nanocomposite films as potential active food packaging material.


Assuntos
Nanocompostos , Nanotubos , Óleos Voláteis , Syzygium , Álcalis , Argila , Óleo de Cravo/química , Embalagem de Alimentos/métodos , Nanocompostos/química , Óleos Voláteis/química , Poliésteres/química , Vapor/análise , Syzygium/química
5.
Environ Pollut ; 312: 120014, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36007793

RESUMO

Polycyclic aromatic compounds (PACs) are organic compounds commonly found in contaminated soil. Previous studies have shown the removal of polycyclic aromatic hydrocarbons (PAHs) in creosote-contaminated soils during steam enhanced extraction (SEE). However, less is known about the removal of alkyl-PAHs and heterocyclic compounds, such as azaarenes, and oxygen- and sulfur-heterocyclic PACs (OPACs and PASHs, respectively). Further, the impact of SEE on the freely dissolved concentration of PACs in soil as well as the soil bioactivity pre- and post-SEE have yet to be addressed. To fulfil these research gaps, chemical and bioanalytical analysis of a creosote-contaminated soil, collected from a U.S. Superfund site, pre- and post-SEE were performed. The decrease of 64 PACs (5-100%) and increase in the concentrations of nine oxygenated-PAHs (OPAHs) (150%) during SEE, some of which are known to be toxic and can potentially contaminate ground water, were observed. The freely dissolved concentrations of PACs in soil were assessed using polyoxymethylene (POM) strips and the concentrations of 66 PACs decreased post-SEE (1-100%). Three in vitro reporter gene bioassays (DR-CALUX®, ERα-CALUX® and anti-AR CALUX®) were used to measure soil bioactivities pre- and post-SEE and all reporter gene bioassays measured soil bioactivity decreases post-SEE. Mass defect suspect screening tentatively identified 27 unique isomers of azaarenes and OPAC in the soil. As a remediation technique, SEE was found to remove alkyl-PAHs and heterocyclic PACs, reduce the concentrations of freely dissolved PACs, and decrease soil bioactivities.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Compostos Policíclicos , Poluentes do Solo , Bioensaio , Creosoto/análise , Receptor alfa de Estrogênio , Oxigênio/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Compostos Policíclicos/análise , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Vapor/análise , Enxofre
6.
Curr Drug Res Rev ; 14(2): 148-156, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754326

RESUMO

BACKGROUND: Prunella vulgaris (PV) is a low-growing perennial herb, which can be found in different parts of the world as Asia, Europe and North America. It is traditionally used for medicinal treatment in various cultures in India, China, Japan, Korea, Russia, and Eastern Europe for treating different ailments, such as fever, and healing wounds. In our previous article, we showed the anti-tumorous effect of the volatile organic compounds (VOCs) of PV and characterized the steam distillation process in the extraction of VOCs from PV. This has never been done before as we are aware of. To use the VOCs as drugs, there is a question of how much of the VOCs are lost before the prepared drugs reach the patients. Thus, the first aim of the present article is to try to explore the time depletion effect on the VOCs in the PV extracts. Then, the second aim is to extend the work in the previous paper and further understand the dynamics of the distillation process of PV by changing the steam flow rate in the extraction process. METHODS: To achieve the first aim to explore the aging effect of how much VOCs are depleted after they are extracted, the VOCs were first extracted by the same method as before, i.e., using steam distillation. Then, tubes of the aqueous solution containing the VOCs were then stored in a 5°C refrigerator. They were then taken out for GC-MS analysis according to a preplanned schedule up to 8 weeks after the VOCs were extracted. The chemical composition of the distillate could then be evaluated. This revealed the changes in the abundance of VOCs with aging. At the same time, the cell viability of SCC154 oral squamous cells treated by these herbal solutions, which were at different aging stages, was evaluated using a tetrazolium-based colorimetric reagent, Cell Counting Kit-8. To achieve the second aim of exploring the dynamics of the steam distillation process, the steam flow rate was adjusted by changing the temperature setting of the hot plate. GC-MS was again used to quantify the chemical constituents of the distillates. RESULTS: By using GC-MS to measure the abundance of volatile compounds at different time points after the distillation process, it was found that the volatile compounds persist for a very long time, or over 8 weeks, which was the longest period of our experiment. The aging of the distillates also did not depreciate much the cell cytotoxicity of the PV distillate on the cancer cells. With respect to the dynamics of the steam distillation process, it was found that, at a low steam flow rate, volatile compounds of lower molecular weight are more efficient to be extracted, while at a high steam flow rate, volatile compounds of higher molecular weight are more efficiently extracted. CONCLUSION: Our findings demonstrate that the VOC compounds extracted and present in aqueous form do not deplete much for at least 2 months after the extraction process, neither they exhibit cell cytotoxicity. The experiments on the dynamics of the steam distillation process demonstrate that the mass of herb present in the flow path of the steam has significant effects on the relative amounts of VOCs extracted.


Assuntos
Prunella , Compostos Orgânicos Voláteis , Destilação/métodos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Extratos Vegetais/farmacologia , Vapor/análise , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologia
7.
J AOAC Int ; 105(6): 1719-1729, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-35608311

RESUMO

BACKGROUND: Origanum vulgare L. essential oil (OEO) is widely known for its good biological activity, but different extraction methods with significant implications on the yield of OEO and the content of the thymol and carvacrol. As an efficient method for extracting essential oils (EO), the supercritical carbon dioxide extraction (SC-CO2) can improve the yield of EOs while protecting their main active components from loss. OBJECTIVE: In this study, the process optimization of SC-CO2 of OEO was carried out. The effects of extraction pressure, temperature, time, and modifier concentration on the composite score of OEO extraction process were investigated. METHOD: Response surface analysis was performed using a Box-Behnken design with three levels and four independent variables. Steam distillation (SD) and lipophilic solvents (n-hexane) extraction (LSE) were compared with SC-CO2 for OEO yields. OEOs extracted by the three methods were qualitatively and semi-quantitatively analyzed by gas chromatography quadrupole-time-of-flight mass spectrometry and gas chromatography-flame ionization detector. RESULTS: The results showed that extraction pressure was the most significant factor affecting the OEO yield, thymol, and carvacrol content. In the optimal conditions (pressure: 217 bar, temperature: 54°C, time: 2 h, modifier concentration: 14%), the yield of OEO reached up to 1.136%, and the contents of thymol and carvacrol reached 53.172 and 41.785 mg/g, respectively. CONCLUSIONS: SC-CO2 was the best extraction method compared to the other two methods. Under the optimal conditions, yield and the content of main components can be effectively improved. It can provide a theoretical basis for the industrial extraction of OEO. HIGHLIGHTS: Taking the comprehensive score as the index, the interaction between the four independent variables in the supercritical fluid extraction process was evaluated by the response surface method. The effects of extraction parameters on the yield of EOs and the contents of thymol and carvacrol were comprehensively investigated.


Assuntos
Cromatografia com Fluido Supercrítico , Óleos Voláteis , Origanum , Origanum/química , Timol/análise , Óleos Voláteis/química , Dióxido de Carbono , Vapor/análise , Cromatografia Gasosa-Espectrometria de Massas , Cromatografia com Fluido Supercrítico/métodos , Solventes/química
8.
Food Chem ; 383: 132547, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35413753

RESUMO

Beetroot (Beta vulgaris) is a source of diverse nutrients such as dietary fibers and betalains. Chinese steamed bread (CSB) has gained popularity in recent years. Red beetroot powder (RBP) was added (up to 70%) in wheat flour to make nutritionally fortified CSB. RBP addition greatly decreased specific volume (1.39 to 0.53 mL/g) and staling rate (4.14 to 2.59%), while increasing hardness (2882 to 15056 g) and chewiness (1923 to 3174 g) since RBP affected gluten secondary structure and weakened dough strength. More importantly, CSB containing RBP exhibited improved in vitro antioxidant potential and reduced estimated glycemic index (70.8 to 60.7). The betalains were largely degraded during steaming due to the isomerization of betanin to isobetanin. Sensory analysis showed that wheat flour could be substituted by RBP up to 10% without compromising the eating quality of the CSB. The findings indicated the feasibility of formulating beetroot-fortified foods with enhanced nutritional quality.


Assuntos
Pão , Farinha , Betalaínas , Pão/análise , Farinha/análise , Pós , Vapor/análise , Triticum/química
9.
Sci Total Environ ; 830: 154820, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35341846

RESUMO

Utilization of renewable energy has become a current energy development trend. In this study, the water footprints of a fuel cell electric vehicle (FCEV) and a compressed natural gas vehicle (CNG) under different fuel scenarios were evaluated. The FCEV exhibits a low water footprint of 27.2 L/100 km under steam methane reforming hydrogen production technology. Hydrogen production using steam methane reforming and water electrolysis via wind can enable the FCEV industry to save more water resources. The percentage difference between different metallic materials in automobiles was analyzed. The water consumption by steel accounted for 73.6% and 80.5%, respectively. The fluctuation law of the water footprint was analyzed based on different power structures and steel water consumption coefficients. It was found that for low steel water consumption coefficient, wind power generation is conducive to slowing down the water consumption during the entire life cycle. In addition, a sensitivity analysis was performed for the FCEV and CNG under different fuel scenarios. Fuel technology and material structure have a significant impact on the total water footprint. The results of this study can provide guidance for the layout of the automobile industry and for water-saving measures in the future.


Assuntos
Gás Natural , Emissões de Veículos , Hidrogênio/análise , Metano/análise , Veículos Automotores , Gás Natural/análise , Vapor/análise , Aço/análise , Emissões de Veículos/análise , Água/análise
10.
J Colloid Interface Sci ; 610: 1043-1056, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34872721

RESUMO

Soybean-oil-based polymer is a promising bio-based water barrier coating on paper packaging but the application is challenged due to its poor water dispersibility. In this present study, 3-aminopropyltriethoxysilane (APTES) modified nanocrystalline cellulose (NCC) was used to implement a stable dispersion of acrylated epoxidized soybean oil (AESO) in water and thus synergistically improved the water vapor barrier properties after coating on paper. APTES-NCC was successfully prepared, and displayed a better interface compatibility with AESO through the Michael addition reaction. Compared with NCC, APTES-NCC displayed an improved hydrophobicity and wettability with AESO, with an increase of contact angle from 38.0° to 76.4°, and a decrease of interfacial tension from 91.5 ± 3.5 mN/m to 82.9 ± 1.8 mN/m. As an emulsifier, APTES-NCC can be more effectively adsorbed on the oil-water interface to form a more stable emulsion than NCC, with a decrease of AESO droplets size from 4.8 µm to 3.1 µm, and a remarkable improvement in static and centrifugal stability. In rheological measurement, the APTES-NCC/AESO emulsion showed a wider linear viscoelastic region (3.4%), better viscoelasticity and thermal curing properties than that of NCC/AESO emulsion, which further explained that the stability of APTES-NCC/AESO emulsion were improved. Therefore, APTES-NCC/AESO emulsion as a coating on paper cured into a continuous barrier film can effectively improve the water vapor barrier properties of paper, and the water vapor transmission rate (WVTR) of paper can be reduced from 1392.8 g/m2•24 h (NCC/AESO emulsion-coated) to 1286.3 g/m2 24 h (APTES-NCC/AESO emulsion-coated), both are significantly lower than that of base paper (1926.7 g/m2•24 h). CLSM testing showed that APTES-NCC could interact effectively with AESO to forming a tight barrier on paper surface and at the same time, sealing the pores inside the paper to resist water vapor penetration. The high-stable AESO emulsion prepared by APTES-NCC is expected to facilitate the utilization of NCC and AESO as a value-added material in making sustainable barrier packaging.


Assuntos
Glycine max , Vapor , Acrilatos , Celulose , Emulsões , Vapor/análise
11.
Int J Biol Macromol ; 173: 193-202, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33482206

RESUMO

Electrosprayed zein nanoparticles containing 10% (w/w) of clove essential oil (CEO) were prepared and then with different levels (5, 10, and 15% w/w) in the starch matrix were used. The incorporation of zein nanoparticles in the structure of starch-based bio-nanocomposites films was confirmed by Fourier transform infrared spectroscopy and field emission scanning electron microscopy. Increasing the level of application of zein bio-nanofillers in the starch film matrix increased thickness and contact angle. However, the use of electrosprayed zein nanoparticles loaded by CEO (EZN-CEO) up to 10% significantly (p < 0.05) reduced the water vapor permeability (WVP), but using 15% of the nanoparticles increased the WVP of the films significantly (p < 0.05). Increasing the EZN-CEO up to 10% significantly (p < 0.05) increased the tensile strength and Young's modulus and reduced the elongation at break of the films. Sustained release of CEO from the bio-nanocomposites showed that the most release of the CEO occurs in 10% ethanol medium. The Fickian diffusion was the predominant mechanism in the release of the CEO, and the Peleg model was selected as the best one to explain the release behavior. The structures designed in this study can be used as an edible coating and bio-preservative in perishable food products.


Assuntos
Óleo de Cravo/química , Preparações de Ação Retardada/química , Nanopartículas Metálicas/química , Nanocompostos/química , Amido/química , Zeína/química , Módulo de Elasticidade , Etanol/química , Embalagem de Alimentos/métodos , Humanos , Nanopartículas Metálicas/ultraestrutura , Nanocompostos/ultraestrutura , Permeabilidade , Vapor/análise , Resistência à Tração
12.
J Sci Food Agric ; 101(8): 3270-3279, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33222204

RESUMO

BACKGROUND: Active packaging containing natural flavonoid has recently emerged as a result of its potential to inhibit the oxidation of foods by interacting with it and/or its surrounding environment, with the aim of counteracting oxidation reactions and extending the shelf-life of foods. The plant Spondias purpurea L. is widely found in northeastern Brazil and is known to contain bioactive flavonoids. The present study aimed to obtain a flavonoid-rich fraction from the pulp of S. purpurea L. and incorporate it into the cellulose acetate film to obtain biodegradable films with antioxidant properties. RESULTS: The fractionation in SiO2 open-column chromatography of the S. purpurea pulp crude extract furnished an antioxidant active fraction containing the flavonols quercetin 3-O-rutinoside and kaempferol 3-O-rutinoside as the major compounds. This active fraction was incorporated (10, 20 and 30 g kg-1 ) into the substance produced with the casting method for cellulose acetate films. The films produced were characterized concerning mechanical properties, water vapor permeability (WVP) and antioxidant activity. CONCLUSION: The incorporation of the active flavonoid fraction from S. purpurea in the cellulose acetate films decreases WVP and elongation at break, at the same time as increasing antioxidant activity, tensile strength and elastic modulus. Thus, the S. purpurea pulps may be an alternative as a source of antioxidants for use in cellulose acetate films. © 2020 Society of Chemical Industry.


Assuntos
Anacardiaceae/química , Antioxidantes/química , Celulose/análogos & derivados , Flavonóis/química , Manipulação de Alimentos/instrumentação , Extratos Vegetais/química , Brasil , Celulose/química , Oxirredução , Permeabilidade , Dióxido de Silício/química , Vapor/análise , Resistência à Tração
13.
Int J Biol Macromol ; 167: 1281-1289, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33217460

RESUMO

A novel antioxidative film was prepared by drying a film-forming solution containing the Flos Sophorae Immaturus extract (FSIE) (0-3.5%) and cassia gum (CG). Scanning electron microscopy (SEM) showed that FSIE was successfully compounded with CG. Although the addition of FSIE slightly increased the water vapor permeability (WVP) and O2 permeability (OP) of the film, it also improved its ability to block ultraviolet light significantly. The appropriate amounts of FSIE increased the tensile strength (TS) from 20.9 MPa to 30.2 MPa but reduced the elongation at break (EB) from 38.7% to 27.6%. The films doped with FSIE exhibited strong antioxidative activity and high rates of free radical scavenging. Total phenols exhibited a positive trend as the amount of FSIE increased in 50% of ethanol. The practical application of these composite films was investigated by evaluating the quality of lard wrapped in the films. After 25 d, the acid value (XAV) and peroxide value (POV) of lard packaged in CG/FSIE2% were lower than the values for lard packaged in CG/FSIE0% and plastic bag. These results showed that the CG/FSIE film had superior antioxidative activity compared to films made from plastic and pure CG.


Assuntos
Antioxidantes/química , Cassia/química , Embalagem de Alimentos/métodos , Extratos Vegetais/química , Gomas Vegetais/química , Sophora/química , Filmes Comestíveis , Temperatura Alta , Microscopia Eletrônica de Varredura , Oxigênio , Permeabilidade , Fenóis/análise , Extratos Vegetais/análise , Gomas Vegetais/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor/análise , Resistência à Tração , Raios Ultravioleta , Difração de Raios X
14.
Medicine (Baltimore) ; 99(50): e23653, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33327350

RESUMO

We aimed to understand the evaluation of different Bowie-Dick test (B-D test) on the performance of pressure steam sterilization equipment in the case of simulated gas leakage, and we selected a pulsating vacuum steam sterilizer to set 4 different gas leakage levels: 1.1, 1.3, 1.5, and 1.7 mbar/min during the B-D test phase. In terms of methods, 4 different brands of B-D test kits (devices) were tested at 4 different leakage rates, and a total of 48 experiments were conducted. The results from univariate analysis revealed that there are statistically significant differences in the judgment of test results among different personnel and brands. The results from multivariate logistic regression analysis displayed that the difference between different personnel was statistically significant (χ = 45.34, P < .001); the difference between different products was statistically significant (χ = 129.37, P < .001); and there was no statistically significant difference between different degree of leakage (χ = 6.99, P > .05). Result judgments of brand 1 and brand 2 are susceptible to subjective factors. The judgment of brand 3 is intuitive and consistent with the evaluation result of brand 4. In conclusion, the order of capacity to evaluate air leakage from best to worst is brand 4→brand 3→brand 1→brand 2.


Assuntos
Vapor/análise , Esterilização/instrumentação , Equipamentos e Provisões Hospitalares/normas , Humanos , Esterilização/normas
15.
Int J Biol Macromol ; 165(Pt B): 2079-2088, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33069820

RESUMO

Alginate nanocomposite films incorporating sepiolite (Sep) modified with myrtle berries extract (MBE) rich in polyphenols were prepared by solution casting method. The effects of different extract concentrations on the film properties were determined by measuring physicochemical, mechanical and antioxidant properties of the films. Fourier transform infrared (FTIR) spectra indicated that strong interactions between the polyphenols present in the MBE and sepiolite were involved in the films. The results suggested that incorporation of Sep-MBE hybrids into the films improved elongation at break, tensile strength, water vapor and UV barrier properties compared to the control film. The antioxidant activity of the films was significantly improved and raised with increasing content of MBE. The release kinetics results of MBE polyphenols from the active films into alcoholic food simulant indicated that the addition of Sep-MBE hybrids to alginate film is able to slow the release of MBE polyphenols. This study revealed the benefits of incorporation of Sep-MBE hybrids into the alginate films and their potential application as active packaging films or coating material.


Assuntos
Alginatos/química , Frutas/química , Silicatos de Magnésio/química , Myrtus/química , Nanocompostos/química , Extratos Vegetais/química , Polifenóis/química , Adsorção , Antioxidantes/farmacologia , Varredura Diferencial de Calorimetria , Módulo de Elasticidade , Umidade , Nanocompostos/ultraestrutura , Fenômenos Ópticos , Permeabilidade , Polifenóis/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor/análise , Temperatura , Resistência à Tração , Termogravimetria , Água/química
16.
Food Environ Virol ; 12(4): 295-309, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32885354

RESUMO

The leading causes of foodborne viral disease outbreaks are human norovirus and hepatitis A virus (HAV). Their environmental persistence enables contamination of kitchen surfaces and crops often consumed raw, such as berries. Many decontamination procedures are inefficient and unsuitable for surfaces of industrial kitchen environments and soft fruits. In this study, we investigated the efficiency of a novel surface decontamination technology, combining steam and ultrasound (steam-ultrasound). Plastic, steel or raspberry surfaces were spiked with the norovirus surrogate, murine norovirus (MNV), and HAV, and steam-ultrasound treated at 85, 90 and 95 °C for 0-5 s. Post treatment viruses were titrated for survival by plaque assay and for genome stability by real-time quantitative PCR (RT-qPCR) of nucleic acid extracts. Survival of viruses were estimated in a log-linear model and the treatment time requirements for each decimal reduction (D value) in viral survival were calculated. The estimated D values of MNV or HAV were 0.4-0.2 or 1.1-0.8 s on plastic, 0.9-0.7 or 1.4-0.8 s on steel and 1.6-1.7 or 3.2-4.7 s on raspberries. No clear trend of genome reduction was observed with tested treatment parameters. Raspberries treated up to 4 s retained its natural texture and visual appeal similar to untreated controls whilst monitored for 7 days. In conclusion, steam-ultrasound treatment can within seconds reduce the titre of foodborne viruses on surfaces of plastic, steel and raspberries. This may particularly benefit industrial scale production of soft fruits for raw consumption and for swift non-hazardous decontamination of industrial kitchen surfaces.


Assuntos
Descontaminação/métodos , Doenças Transmitidas por Alimentos/virologia , Vírus da Hepatite A/efeitos da radiação , Norovirus/efeitos da radiação , Plásticos/análise , Rubus/virologia , Aço/análise , Ultrassom/métodos , Animais , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos/instrumentação , Frutas/virologia , Vírus da Hepatite A/genética , Vírus da Hepatite A/fisiologia , Humanos , Camundongos , Norovirus/genética , Norovirus/fisiologia , Vapor/análise , Inativação de Vírus/efeitos da radiação
17.
J Agric Food Chem ; 68(34): 9150-9157, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32786862

RESUMO

As bio-based food packaging materials promise a more sustainable future, this work fabricated edible oleofilms by casting beeswax-in-water Pickering emulsions, which were formed by the physical hybrid particles of bacterial cellulose nanofibrils (BCNFs) and carboxymethyl chitosan (CCS) (BC/CCS). The emulsion droplet size was varied from 4 to 9 µm, and the emulsion index (EI) was all up to 100%. The obtained emulsions exhibited excellent long-term stability, and there was no change in the EI (100%) after the storage of the emulsion for 3 months. Moreover, the environmental temperature had almost no impact on the droplet size and EI of the emulsion. The mechanical properties of the oleofilms were significantly improved by enhancing the content of BC/CCS. There was also a visual reduction in the water vapor permeability (WVP) value, which was lower than 1.1 × 10-7 g·m-1·h-1·Pa-1. Furthermore, the obtained oleofilms exhibited a notable improvement in surface hydrophobicity, and surprisingly, it could be easily redispersed into water to recover back to the emulsion state without additional high energy mixing. This suggested that this edible oleofilm was prepared by a fully green method by casting Pickering emulsions stabilized by BC/CCS and could extend its application for the development of food-grade coating materials.


Assuntos
Celulose/química , Embalagem de Alimentos/instrumentação , Nanoestruturas/química , Bactérias/química , Bactérias/metabolismo , Celulose/metabolismo , Emulsões/química , Interações Hidrofóbicas e Hidrofílicas , Compostos Orgânicos/química , Permeabilidade , Vapor/análise , Ceras/química
18.
PLoS One ; 14(12): e0226764, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31869376

RESUMO

Parallel to establishment of diagnostic surveillance protocols for detection of prostatic diseases, novel treatment strategies should be developed. The aim of the present study is to evaluate the feasibility and possible side effects of transrectal, MRI-targeted intraprostatic steam application in dogs as an established large animal translational model for prostatic diseases in humans. Twelve healthy experimental, intact, male beagle dogs without evidence of prostatic pathology were recruited. An initial MRI examination was performed, and MRI-targeted steam was applied intraprostatically immediately thereafter. Serum levels of C-reactive protein (CRP), clinical and ultrasonographic examinations were performed periodically following the procedure to assess treatment effect. Four weeks after treatment, all dogs underwent follow-up MRI examinations and three needle-core biopsies were obtained from each prostatic lobe. Descriptive statistics were performed. MRI-guided intraprostatic steam application was successfully performed in the study population. The first day after steam application, 7/12 dogs had minimal signs of discomfort (grade 1/24 evaluated with the short-form Glasgow Composite Measure Pain Scale) and no dogs showed any sign of discomfort by day 6. CRP elevations were detected in 9/12 dogs during the first week post steam application. Mild to moderate T2 hyperintense intraparenchymal lesions were identified during follow-up MRI in 11/12 dogs four weeks post procedure. Ten of these lesions enhanced mild to moderately after contrast administration. Coagulative necrosis or associated chronic inflammatory response was detected in 80.6% (58/72) of the samples obtained. MRI-targeted intraprostatic steam application is a feasible technique and displays minimal side effects in healthy dogs as translational model for human prostatic diseases. This opens the possibility of minimally invasive novel treatment strategies for intraprostatic lesions.


Assuntos
Técnicas de Ablação/métodos , Imageamento por Ressonância Magnética/métodos , Próstata/cirurgia , Doenças Prostáticas/cirurgia , Animais , Cães , Estudos de Viabilidade , Masculino , Próstata/diagnóstico por imagem , Doenças Prostáticas/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Vapor/análise
19.
Anal Chem ; 91(22): 14239-14246, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31648517

RESUMO

An off-resonance broadband photoacoustic spectroscopy (PAS) technique with a supercontinuum laser (SCL) in the near-infrared range is demonstrated for biogas measurements with different biomass matrices. The PAS sensor system has been calibrated with known concentrations of methane (CH4), carbon dioxide (CO2), water vapor (H2O vapor), and hydrogen sulfide (H2S). A laboratory-scale bioreactor was set up to monitor CH4 and CO2 generation using the SCL-PA sensor system. The obtained results show the suitability of the PAS sensor to be employed in a fully operational large scale biogas plant for online monitoring. The periodic variations in concentration for CH4, CO2, and H2O vapor were monitored in a large scale cattle dung based biogas plant in real-time, and the operating ranges were measured to be around 50-65%, 34-48%, and 0-1%, respectively. The SCL-PA sensor was also employed at two different Sewage Treatment Plants in Chennai, Tamilnadu, India, where along with CH4 (60-63%), CO2 (34-38%), and H2O vapor (0.8-1%), trace concentration levels of H2S were found to be around 0.04-1%.


Assuntos
Dióxido de Carbono/análise , Sulfeto de Hidrogênio/análise , Metano/análise , Técnicas Fotoacústicas/métodos , Vapor/análise , Biomassa , Desenho de Equipamento , Lasers , Técnicas Fotoacústicas/instrumentação , Esgotos/análise , Análise Espectral/instrumentação , Análise Espectral/métodos
20.
J Food Biochem ; 43(3): e12732, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31353539

RESUMO

In this work, the influence of the method of processing on phenolic composition and the in vitro antioxidant activity (AOX) of grape juices was studied. The classic methods of producing "Hot Press" (HP), "Hot Break" (HB), and "Cold Press" (CP), and an artisanal method using steam were compared. Among the methods of elaboration of evaluated grape juices, those that heated the grape showed higher content of bioactive phenolics and AOX. The artisanal method using steam presented acceptable bioactive content and could be simple alternative for grape juice production. The main bioactive compounds quantified in the studied juices were procyanidin B1, quercetin-3-pyranoside, chlorogenic acid, malvidin-3-glucoside, cyanidin-3-glucoside, and petunidin-3-glucoside. These were correlated by principal component analysis (PCA) with the antioxidant activity. The characteristics obtained from the different juice elaboration methods demonstrate that the HB method was responsible for the greatest extraction of bioactive compounds from the grapes. PRACTICAL APPLICATIONS: Worldwide consumption of grape juice has been increasing. The factors that have contributed to this growth include the good sensory acceptance and the nutritional appeal related to bioactive compounds. The bioactive compounds of grape juice are mainly flavonoids and phenolic acids, and several factors exert influence on the phenolic composition of this beverage, among them, the method of elaboration. The present work presents new information on the influence of grape juice processing methods on the profile of bioactive compounds of nutritional interest and contributes to improvements in the production processes of this beverage.


Assuntos
Manipulação de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Fenóis/química , Vitis/química , Frutas/química , Temperatura Alta , Vapor/análise
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