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1.
J Texture Stud ; 55(2): e12830, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38581175

RESUMO

Freezing and blanching are essential processing steps in the production of frozen yellow peaches, inevitably leading to texture softening of the fruit. In this study, the synergistic mechanism of stem blanching, freezing conditions (-20°C, -40°C, -80°C, and liquid nitrogen [-173°C]), and sample sizes (cubes, slices, and half peaches) on macroscopic properties of texture, cellular structure, and ice crystal size distribution of frozen yellow peaches were measured. Blanching enhanced the heat and mass transfer rates in the subsequent freezing process. For nonblanched samples, cell membrane integrity was lost at any freezing rate, causing a significant reduction in textural quality. Slow freezing further exacerbated the texture softening, while the ultra-rapid freezing caused structural rupture. For blanched samples, the half peaches softened the most. The water holding capacity and fracture stress were not significantly affected by changes in freezing rate, although the ice crystal size distribution was more susceptible to the freezing rate. Peach cubes that had undergone blanching and rapid freezing (-80°C) experienced 4% less drip loss than nonblanched samples. However, blanching softened yellow peaches more than any freezing conditions. The implementation of uniform and shorter duration blanching, along with rapid freezing, has been proven to be more effective in preserving the texture of frozen yellow peaches. Optimization of the blanching process may be more important than increasing the freezing rate to improve the textural quality of frozen yellow peaches.


Assuntos
Prunus persica , Vapor , Congelamento , Conservação de Alimentos , Gelo
2.
Molecules ; 29(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38611810

RESUMO

A single combi oven, known for its versatility, is an excellent choice for a variety of chicken soup preparations. However, the impact of universal steam ovens on the flavor quality of chicken soup remains unclear. This study aimed to explore the impact of different cooking methods on the aroma and taste of chicken soup. Three cooking methods with various stewing times were compared: ceramic pot (CP), electric pressure cooker (EPC), and combi oven (CO). Analyses were conducted using electron-nose, electron-tongue, gas chromatography-ion mobility spectrometry (GC-IMS), automatic amino acid analysis, and chemometric methods. A total of 14 amino acids, including significant umami contributors, were identified. The taste components of CP and CO chicken soups were relatively similar. In total, 39 volatile aroma compounds, predominantly aldehydes, ketones, and alcohols, were identified. Aldehydes were the most abundant compounds, and 23 key aroma compounds were identified. Pearson's correlation analyses revealed distinct correlations between various amino acids (e.g., glutamic acid and serine) and specific volatile compounds. The aroma compounds from the CP and CO samples showed similarities. The results of this study provide a reference for the application of one-touch cooking of chicken soup in versatile steam ovens.


Assuntos
Antifibrinolíticos , Odorantes , Animais , Galinhas , Vapor , Paladar , Cromatografia Gasosa-Espectrometria de Massas , Aminoácidos , Aldeídos , Culinária
3.
Sensors (Basel) ; 24(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38610546

RESUMO

The study of plant electrophysiology offers promising techniques to track plant health and stress in vivo for both agricultural and environmental monitoring applications. Use of superficial electrodes on the plant body to record surface potentials may provide new phenotyping insights. Bacterial nanocellulose (BNC) is a flexible, optically translucent, and water-vapor-permeable material with low manufacturing costs, making it an ideal substrate for non-invasive and non-destructive plant electrodes. This work presents BNC electrodes with screen-printed carbon (graphite) ink-based conductive traces and pads. It investigates the potential of these electrodes for plant surface electrophysiology measurements in comparison to commercially available standard wet gel and needle electrodes. The electrochemically active surface area and impedance of the BNC electrodes varied based on the annealing temperature and time over the ranges of 50 °C to 90 °C and 5 to 60 min, respectively. The water vapor transfer rate and optical transmittance of the BNC substrate were measured to estimate the level of occlusion caused by these surface electrodes on the plant tissue. The total reduction in chlorophyll content under the electrodes was measured after the electrodes were placed on maize leaves for up to 300 h, showing that the BNC caused only a 16% reduction. Maize leaf transpiration was reduced by only 20% under the BNC electrodes after 72 h compared to a 60% reduction under wet gel electrodes in 48 h. On three different model plants, BNC-carbon ink surface electrodes and standard invasive needle electrodes were shown to have a comparable signal quality, with a correlation coefficient of >0.9, when measuring surface biopotentials induced by acute environmental stressors. These are strong indications of the superior performance of the BNC substrate with screen-printed graphite ink as an electrode material for plant surface biopotential recordings.


Assuntos
Grafite , Agricultura , Transporte Biológico , Carbono , Clorofila , Vapor
4.
Molecules ; 29(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38611838

RESUMO

The rhizome of Polygonatum cyrtonema Hua has been used as a traditional Chinese medicine for over 2000 years. The fresh Chinese herb possesses micro toxicity and is thus traditionally alternately steamed and basked nine times to alleviate the toxicity and enhance the pharmaceutical efficacy. Different processing cycles usually result in variable therapeutic effects in the processed Polygonatum cyrtonema Hua (P-PCH). However, it can be hard to tell these various P-PCHs apart at present. To identify the P-PCHs that had undergone repeated steaming one to nine times, the chemical constituents were profiled based on Ultra-Performance Liquid Chromatography with Quadruple-Time-of-Flight Mass Spectrometry, and the Principal Component Analysis and Cluster Analysis methods were adopted to discriminate different cycles of P-PCH. A total of 44 characteristic markers were identified, which allowed the P-PCHs to be discriminated exactly.


Assuntos
Gastrópodes , Polygonatum , Animais , Análise por Conglomerados , Espectrometria de Massas , Vapor , Cromatografia Líquida
5.
Food Res Int ; 185: 114292, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38658072

RESUMO

The synthetic, non-renewable nature and harmful effects of plastic packaging have led to the synthesis of eco-friendly renewable bio-nanocomposite film. The present work was aimed at the formulation and characterization of bio-nanocomposite film using soybean meal protein, montmorillonite (MMT), and debittered kinnow peel powder. The composition of film includes protein isolate (5% w/v), glycerol (50% w/w), peel powder (20% w/w), and MMT (0.5-2.5% w/w). Incorporation of MMT in soybean meal protein-based film loaded with kinnow peel powder showed lesser solubility (16.76-26.32%), and swelling ability (142.77-184.21%) than the film prepared without MMT (29.41%, & 229.41%, respectively). The mechanical properties like tensile strength of nanocomposite film improved from 9.41 to 38.69% with the increasing concentration of MMT. The water vapor transmission rate of the nanocomposite film was decreased by 3.45-17.85% when the MMT concentration increased. Fourier-transform infrared spectroscopy and X-ray diffraction analysis showed no considerable change in the structural properties of the film after the addition of MMT. Differential scanning colorimeter analysis revealed the increment in melting temperature (85.33-92.67 °C) of the film with a higher concentration of MMT. Scanning electron microscopy analysis indicated an increased distributed area of MMT throughout the film at higher concentrations. The antimicrobial activity of the film was remarkably increased by 4.96-17.18% with the addition of MMT. The results obtained in the current work confirmed that MMT incorporation in soybean meal protein-based film can augment its properties and can be utilized for enhancing the storage period of food products.


Assuntos
Bentonita , Embalagem de Alimentos , Nanocompostos , Pós , Proteínas de Soja , Resistência à Tração , Bentonita/química , Nanocompostos/química , Proteínas de Soja/química , Embalagem de Alimentos/métodos , Soja/química , Solubilidade , Vapor
6.
Med Sci Monit ; 30: e942601, 2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38493296

RESUMO

BACKGROUND Central sterile supply departments (CSSDs) play a vital role in hospital infection control. We investigate the factors associated with wet pack occurrence after steam sterilization. MATERIAL AND METHODS We designed a log sheet to record information concerning sterilized packs. The data included the type of sterilized pack; outside weather (sunny, overcast, or rainy); the item in the sterilized pack; packaging material; whether the item had been packaged in compliance with guidelines; whether the pack had been laid flat, upright, or leaning at an acute angle; which sterilizer was used for sterilization of the pack; whether the pack had been placed on the top or bottom shelf inside the sterilizer chamber; whether the pack had been loaded in compliance with guidelines; the drying time following sterilization; and cooling time after sterilization. The sterilized packs in our study were selected from all of the packs that were sterilized in the CSSD of the authors' institution during June to December 2021. RESULTS Factors associated with wet pack occurrence after steam sterilization include: outside weather on the day of sterilization; the item in the sterilized pack; packaging material; whether the item had been packaged in compliance with guidelines; whether the pack had been placed on the top or bottom shelf; and cooling time after sterilization. Statistically significant differences (P<0.05) in wet pack incidence were identified for all of these factors. CONCLUSIONS Various factors are associated with wet pack occurrence after steam sterilization. Recommendations for reducing the risk of wet packs include regular maintenance of the steam pipeline, regular replacement of thermal insulation materials for the steam pipeline, and extension of the drying time.


Assuntos
Vapor , Esterilização , Incidência , Esterilização/métodos , Hospitais , China/epidemiologia
7.
Biosensors (Basel) ; 14(3)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38534221

RESUMO

In a chamber-based digital PCR (dPCR) chip fabricated with polydimethylsiloxane (PDMS), bubble generation in the chambers at high temperatures is a critical issue. Here, we found that the main reason for bubble formation in PDMS chips is the too-high saturated vapor pressure of water at an elevated temperature. The bubbles should be completely prevented by reducing the initial pressure of the system to under 13.6 kPa to eliminate the effects of increased-pressure water vapor. Then, a cavity was designed and fabricated above the PCR reaction layer, and Parylene C was used as a shell covering the chip. The cavity was used for the negative generator in sample loading, PDMS degassing, PCR solution degassing in the digitization process and water storage in the thermal reaction process. The analysis was confirmed and finally achieved a desirable bubble-free, fast-digitization, valve-free and no-tubing connection dPCR.


Assuntos
Dimetilpolisiloxanos , Vapor , Reação em Cadeia da Polimerase
8.
Food Chem ; 447: 138932, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38484546

RESUMO

The thawing method is critical for the final quality of products based on the frozen dough. The effects of ultrasound thawing, proofer thawing, refrigerator thawing, water bath thawing, ambient thawing, and microwave thawing on the rheology, texture, water distribution, fermentation characteristics, and microstructure of frozen dough and the properties of steamed bread were investigated. The results indicated that the ultrasound thawing dough had better physicochemical properties than other doughs. It was found that ultrasound thawing restrained the water migration of dough, improved its rheological properties and fermentation capacity. The total gas volume value of the ultrasound thawing dough was reduced by 21.35% compared with that of unfrozen dough. The ultrasound thawing dough displayed a thoroughly uniform starch-gluten network, and an enhanced the specific volume and internal structure of the steamed bread. In conclusion, ultrasound thawing effectively mitigated the degradation of the frozen dough and enhanced the quality of steamed bread.


Assuntos
Pão , Vapor , Pão/análise , Água/química , Glutens/química , Congelamento , Farinha/análise
9.
J Food Sci ; 89(4): 2371-2383, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38488724

RESUMO

The "instant" quality of instant rice noodles is significantly affected by slow rehydration during cooking. This happens as a result of the native rice starch's low ability to gelatinize as well as the high shear and pressure utilized in industries during the widely used extrusion molding process. In order to address this issue, the rice flour was pretreated with mild steam (MS) technology. The results revealed that the rehydration qualities of the rice noodles that were extruded from the steam-treated flour significantly improved. There was a reduction of 25.5% in the rehydration time, from 443 to 330 s. The MS-treated rice starch's peak viscosity increased to 4503 from 4044 mPa/s. Decreases in gelatinization enthalpy (ΔH) and short-range ordering also suggest a reduction in difficulty in accomplishing starch gelatinization. Scanning electron microscopy studies showed particle aggregation increased as the treatment duration lasted longer. In conclusion, our findings indicate that we successfully addressed the issue of slow rehydration in instant rice noodles while presenting a novel approach for their manufacturing in the manufacturing sector.


Assuntos
Oryza , Vapor , Oryza/química , Culinária , Amido/química , Viscosidade , Farinha/análise
10.
Int J Biol Macromol ; 265(Pt 1): 130837, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503372

RESUMO

Efficient and effective use of biopolymers, such as starch, has increasingly prompted interest due to the current environmental challenges. However, starch-based composites still show poor ductility along with water and oxygen permeability, which may not meet the requirements for food packaging standards. In this study, modified starch (m-St), isolated from the avocado seed and synthesized with tert-butyl acetoacetate (t-BAA), was embedded into polylactic acid (PLA) to design new eco-friendly composites. The developed biocomposites were found to exhibit high performance with outstanding mechanical properties in conjunction with remarkable light, water vapor, and oxygen blocking features for food packaging applications. PLA/m-St(1:6) 20 wt% composites showed a dramatic increase in elongation at break (EB%) from 3.35 to 27.80 % (about 730 % enhancement) and exhibited remarkable UV-blocking performance from 16.21 to 83.86 % for UVB, relative to pure PLA. Equally importantly, these biocomposites revealed significant improvement in oxygen and water vapor barrier performance by reducing their values from 1331 to 32.9 cc m-2 day-1 (indicating a remarkable reduction of 97.53 %) and 61.9 to 28 g m-2 day-1, respectively. This study can show the great potential of extracting starch from biowaste resources and transforming it into sustainable bio-based composites as a promising solution for food packaging applications.


Assuntos
Persea , Embalagem de Alimentos , Amido , Vapor , Poliésteres , Oxigênio
11.
Altern Ther Health Med ; 30(2): 42-49, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38518168

RESUMO

Background: Most post-COVID-19 patients had physiological health problems, which differed for each patient. The potential treatment for post-COVID-19 syndrome must require multi-disciplinary approaches that focus on individualized treatment. Therefore, traditional Thai Medicine (TTM) clinical practice guidelines for post-COVID-19 treatment are developed by the Traditional Thai Medicine Hospital, Prince of Songkla University, to care for post-COVID-19 patients. Objective: This current study aimed to investigate the effect of the guidelines on post-COVID-19 patient's physical health. Methods: This research was a retrospective clinical study, carried out from June 2022 to July 2022. Setting: The study was conducted at the Traditional Thai Medicine Hospital, Prince of Songkla University, and La Flora Khao Lak TTM clinic, Thailand. Participants: Data (n=17) were collected from the medical record. They were included if they met the following criteria: patients were more than 18 years old, had a medical history of COVID-19 disease, had fully recovered from the disease (ATK for COVID-19 is negative) at least a week before starting the guideline, and had complete medical information such as post-COVID-19 symptoms, vital signs, pain score, cough severity score, and quality of life examination. Intervention: Approaches for post-COVID-19 treatment included herbal Thai medicine recipes, Thai massage, herbal steam inhalation, herbal hot steam, herbal hot water immersion, acupressure massage for breathing stimulation, and a breathing exercise. All procedures were applied for 7 days continually or until they have recovered. Primary Outcome Measures: The effects of TTM approaches on the symptoms of post-COVID-19 patients on pain score, quality of life, cough severity were measured using a visual analog score (VAS), SF-36 questionnaire, and cough severity index (CSI), respectively. Results: The average duration time of post-COVID-19 syndrome was 25.76 days, and the most common symptom was muscle pain/stress (10; 71.43%). Yahom-Navakot (6; 42.86%) is the most common recipe used for the treatment. Interestingly, the pain score was significantly reduced by 3 days of the treatment (4.88±2.03 vs 2.29±2.08 ). Moreover, the cough severity index (12.86±11.55 vs 3.31±6.38) was significantly lessened by 7 days of the treatment. Remarkably, most symptoms vanished entirely after 7 days of the intervention, leading to a better quality of life for the patients (53.24±22.15 vs 65.59±23.64). Conclusions: The TTM clinical practice guideline for treating post-COVID-19 syndrome effectively improved the overall physical health capacity and symptoms associated with post-COVID-19 syndrome. Therefore, the implementation of this guideline, together with other approaches, could strengthen the treatment for post-COVID-19 to be more effective.


Assuntos
COVID-19 , Plantas Medicinais , Humanos , Adolescente , Síndrome Pós-COVID-19 Aguda , 60711 , Tailândia/epidemiologia , Qualidade de Vida , Tratamento Farmacológico da COVID-19 , Estudos Retrospectivos , Vapor , COVID-19/terapia , Dor , Tosse
12.
J Mech Behav Biomed Mater ; 153: 106507, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38503082

RESUMO

Polyolefins exhibit robust mechanical and chemical properties and can be applied in the medical field, e.g. for the manufacturing of dentures. Despite their wide range of applications, they are rarely used in extrusion-based printing due to their warpage tendency. The aim of this study was to investigate and reduce the warpage of polyolefins compared to commonly used filaments after additive manufacturing (AM) and sterilization using finite element simulation. Three types of filaments were investigated: a medical-grade polypropylene (PP), a glass-fiber reinforced polypropylene (PP-GF), and a biocopolyester (BE) filament, and they were compared to an acrylic resin (AR) for material jetting. Square specimens, standardized samples prone to warpage, and denture bases (n = 10 of each group), as clinically relevant and anatomically shaped reference, were digitized after AM and steam sterilization (134 °C). To determine warpage, the volume underneath the square specimens was calculated, while the deviations of the denture bases from the printing file were measured using root mean square (RMS) values. To reduce the warpage of the PP denture base, a simulation of the printing file based on thermomechanical calculations was performed. Statistical analysis was conducted using the Kruskal-Wallis test, followed by Dunn's test for multiple comparisons. The results showed that PP exhibited the greatest warpage of the square specimens after AM, while PP-GF, BE, and AR showed minimal warpage before sterilization. However, warpage increased for PP-GF, BE and AR during sterilization, whereas PP remained more stable. After AM, denture bases made of PP showed the highest warpage. Through simulation-based optimization, warpage of the PP denture base was successfully reduced by 25%. In contrast to the reference materials, PP demonstrated greater dimensional stability during sterilization, making it a potential alternative for medical applications. Nevertheless, reducing warpage during the cooling process after AM remains necessary, and simulation-based optimization holds promise in addressing this issue.


Assuntos
Polipropilenos , Vapor , Polienos , Resinas Acrílicas/química , Esterilização
13.
Chemosphere ; 353: 141638, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38442775

RESUMO

Condensable particulate matter (CPM) from coal combustion is the focus of current pollutant emission studies, and CPM can be divided into inorganic and organic fractions according to the component characteristics. At present, the effects of different factors in the combustion process on the organic and inorganic components of CPM have not been discussed systematically. Here, we conducted combustion experiments collected the generated CPM on a well-controlled drip tube furnace, and investigated the effects of different factors on the generation of organic and inorganic components of CPM by varying the furnace wall insulation temperature, the ratio of gas supply components and the water vapor content in the flue gas. The results showed that the increase in combustion temperature (1300-1500 °C) and oxygen concentration (15-25%) reduced the total CPM generation by 9.8% and 19.98%, respectively, and the intervention of water vapor increased the ability of the whole CPM sampling device to capture ultrafine condensable particles. The generation of CPM organic components decreased with the enhancement of combustion temperature and oxygen content on combustion characteristics, and alkanes shifted to low carbon content. The amount of CPM inorganic components increased with the increase of water vapor content in the flue gas, and this change was dominated by SO42-. The above results provide a feasible idea for the next step of the precise reduction of CPM components.


Assuntos
Poluentes Atmosféricos , Material Particulado , Material Particulado/análise , Poluentes Atmosféricos/análise , Carvão Mineral , Vapor , Centrais Elétricas , Oxigênio
15.
Environ Sci Pollut Res Int ; 31(17): 25312-25328, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38472579

RESUMO

It was aimed to determine the specific resource use and reduction potential profiles in various textile sub-sectors (cotton woven fabric dyeing-finishing, wool woven fabric dyeing-finishing, synthetic woven fabric dyeing-finishing, cotton knitted fabric, synthetic knit fabric dyeing-finishing, non-woven fabric, dyeing-finishing of knitted fabric). The main focus was to elucidate opportunities for sustainability in terms of decreasing resource utilization in the textile sector. On-site surveys and detailed data collection studies were carried out at 150 textile facilities. Average specific values for water, auxiliary chemicals, dyestuff, electricity, and steam consumptions, and related reduction potentials were calculated and compared within facilities and sub-sectors. The minimum specific resource consumption values reported in the Best Available Techniques Reference Document (BREF) for the textile industry and data of similar facilities from the literature were evaluated and used. A detailed environmental performance profile of the Turkish textile sector in terms of resource usage and reduction potential was generated. The highest specific water consumption was found in the wool-woven fabric sub-sector (345 ± 262 L/kg product). Although the specific auxiliary chemical consumption shows similarities within sub-sectors, the highest specific auxiliary chemical consumption (397 ± 237 g/kg product) was found in the synthetic woven fabric sub-sector. The sub-sector with the highest specific dyestuff consumption (30 ± 13 g/kg product) was the cotton knitted fabric sub-sector. The wool woven fabric industry had the highest specific electricity (7 ± 5.3 kWh/kg product) and steam (20 ± 11 kg steam/kg product) consumption. In addition, for all the studied sub-sectors country-wide, the lowest and highest reduction potentials in resource uses were 18 ± 15% and 73 ± 13%, respectively, suggesting a need for major full-scale implementations of cleaner production for enhancing sustainability in the textile industry.


Assuntos
Vapor , Indústria Têxtil , Animais , Têxteis , Fibra de Lã , Corantes
16.
Food Res Int ; 181: 114109, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38448097

RESUMO

Microplastics are a complex mix of chemicals containing polymers and certain plastic additives such as bisphenols and phthalates. These particles are porous materials that can also sorb contaminants from their surroundings, and leach chemicals from the particle under certain circumstances. Aquatic animals can ingest microplastic particles, which mostly bioaccumulate in the gastrointestinal tract of animals. In terms of dietary exposure, small animals consumed whole such as mussels, contribute more to the dietary intake of microplastic particles. Plastic additives and contaminants are not chemically bound to the polymers, and certain processing methods or cooking processes result in the release of these chemicals that leach from the plastic particles, leaving them more available for absorption when ingested. Analytical methods are crucial for a better understanding of the occurrence of plastic additives and contaminants in aquatic products, and to know certain circumstances and treatments that influence human exposure. This study uses an MSPD-HPLC methodology for the simultaneous determination of 9 analytes (BPA, BPF, BPS, DEP, DBP, DEHP, DDD, DDT, and DDE) analyzing, for the first time, the occurrence of these chemicals in raw, steamed and canned mussels of two different harvesting areas (Atlantic and the Mediterranean), becoming one of the most efficient methodologies for determining the presence of these analytes in very complex food matrices, able to define the changes in cooking and processing activities. The results showed that the heat and pressure treatment could influence the migration of plastic additives from microplastic particles present in mussels to the cooking liquids.


Assuntos
Bivalves , Plásticos , Animais , Humanos , Cromatografia Líquida de Alta Pressão , Microplásticos , Alimentos Marinhos , Vapor
17.
Waste Manag ; 179: 163-174, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38479255

RESUMO

Catalytic tar cracking is a promising technique for hot syngas cleaning unit in gasification plants because it can preserve tars chemical energy, so increasing the syngas heating value. The cost associated with catalyst preparation is a key issue, together with its deactivation induced by coke deposition. Iron is a cheap and frequently used catalyst, which can also be found in some industrial wastes. The study aims to assess the catalytic efficiency for tar cracking of two waste-derived materials (red mud and sewage sludge) having high content of iron. The catalysts were supported on spheres of γ-Al2O3, and their efficiency was compared to that of a pure iron catalyst. The role of support was investigated by testing pure red mud, with and without the support. A series of long-term tests using naphthalene as tar model compound were carried out under different values of process temperatures (750 °C-800 °C) and steam concentrations (0 %-7.5 %). The waste derived catalysts showed lower hydrogen yields compared to pure iron catalyst, due to their lower content of iron. On the other hand, the conversion efficiencies of all the tested catalysts resulted rather similar, since the Alkali and Alkaline-Earth Metallic species present on the surface of waste-derived catalyst help in preventing coke deposition. The iron oxidation state appears to play an important role, with reduced iron more active than its oxidised form in the tar cracking reactions. This indicates the importance of tuning steam concentration to keep constant the reduced state of iron while limiting coke deposition.


Assuntos
Coque , Vapor , Hidrogênio/análise , Ferro , Alcatrões/química , Biomassa , Catálise
18.
Int J Med Mushrooms ; 26(4): 73-82, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38523451

RESUMO

This paper evaluated the effect of different substrate disinfection methods viz. hot water treatment, autoclaving and steam pasteurization at 100°C, 121°C, and 65°C, respectively, on yield of Hypsizygus ulmarius and effects of sun drying, oven drying and cabinet drying techniques at 25 ± 2°C, 40 ± 2°C, and 50 ± 2°C, respectively, on nutritional qualities of H. ulmarius. Hot water treated substrate gave higher yield (215.36 ± 1.49 g) and biological efficiency (71.78%) compared with autoclaved (194.45 ± 3.36 g and 64.81%) and steam pasteurized substrate (194.45 ± 3.36 g and 65.28%). The different drying methods used for drying the fruit bodies significantly influenced the nutrient profile of H. ulmarius. Highest moisture (6.95%), fiber (16.94%) and protein content (22.49%) was retained in sun dried fruit bodies whereas ash content (5.52%) was highest for oven dried fruit bodies. Cabinet dried fruit bodies showed significantly higher percentage of fats (1.82%) and carbohydrates (53.58%). In the DPPH assay the cabinet dried fruit bodies showed the highest antioxidant activity followed by sun dried and oven dried fruit bodies with respective IC50 values as 104.21 ± 0.14, 117.17 ± 0.07 and 163.57 ± 0.02. The drying methods proved to be effective in controlling the bacterial growth for a period of two months after which significant bacterial growth was noted.


Assuntos
Agaricales , Pleurotus , Vapor , Desinfecção , Antioxidantes/farmacologia
19.
Chemosphere ; 355: 141750, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522671

RESUMO

Activated carbon (AC) has important industrial and environmental applications as it has excellent abilities to sorb contaminants such as per- and polyfluoroalkyl substances (PFAS). Current research aims to develop activated biochars (AB) from renewable biomass to replace AC that is produced from fossil feedstock. Both AC and AB are primarily comprised of condensed aromatic carbon (ConAC), the component that is the focus of this study. ConAC is characterized to determine its relationship with biochar activation conditions and PFAS sorption, which are understudied at present. Benzenepolycarboxylic acid (BPCA) markers for ConAC were quantified in steam-activated biochars (AB-Steam) and carbon dioxide-activated biochars (AB-CO2) prepared from waste timber at different temperatures (800, 850, 900 °C) and molar ratios of feedstock-carbon:steam (0.50 - 1.25). A non-activated biochar was also included as a reference. ConAC relative to total organic carbon content was higher in AB-Steam than in AB-CO2 (92 ± 2 % vs. 81 ± 11%). The ratio of benzenehexa- (B6CA) to benzenepentacarboxylic (B5CA) acids revealed that AB-Steam also had larger ConAC clusters than AB-CO2. These findings provide novel evidence that steam activation is more effective than CO2 activation in creating ConAC. To assess how ConAC impacts AB sorption abilities, AB-Steam were used to remediate PFAS from contaminated soils. The observed strong correlations between ConAC content and sorption of long-chain PFAS suggest the importance of hydrophobic interactions between PFAS tails and ConAC. Poor correlations for short-chain PFAS, on the other hand, indicated the existence of electrostatic repulsion interactions between PFAS head groups and ConAC. Collectively, these results explain the great ability of AB-Steam to sorb PFAS from contaminated soils (up to 100% remediation). More broadly, this work demonstrates that the BPCA method can be a valuable tool to assess the quality of biochars and other carbonaceous sorbents in relation to their production conditions or contaminant sorption abilities.


Assuntos
Dióxido de Carbono , Fluorocarbonos , Vapor , Adsorção , Carvão Vegetal/química , Solo
20.
Int J Biol Macromol ; 265(Pt 2): 131116, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38522704

RESUMO

Dictyophora indusiata is medicinal and edible fungi containing various nutrients. The aim of this study was to investigate the efficient extraction and structural evolution of Dictyophora indusiata polysaccharide during the vitro digestion based on steam explosion pretreatment methods. In this study, the extraction rate of Dictyophora indusiata polysaccharide was optimized by steam explosion pretreatment methods, which was 2.46 folds that of the water extraction method. In addition, the digestion and fermentation properties of Dictyophora indusiata polysaccharide before and after steam explosion were evaluated in vitro by the changes of molecular weights, total and reducing sugars levels, surface morphology and functional groups, which showed that the structure of Dictyophora indusiata polysaccharide remained stable after salivary-gastric digestion, and partially entered the large intestine, where it could be utilized by gut microbiota. Dictyophora indusiata polysaccharide promoted the increase of beneficial bacteria Megamonas and increased the content of acetic acid, propionic acid and butyric acid, which was 2.17, 2.81, 2.43 folds that of the CON group after fermentation for 24 h, and 1.87, 2.77, 1.90 folds that of the CON group after fermentation for 48 h, respectively. This study will provide theoretical basis for the high value utilization of Dictyophora indusiata polysaccharide.


Assuntos
Basidiomycota , Vapor , Basidiomycota/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Água
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