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1.
Water Sci Technol ; 89(10): 2593-2604, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38822602

RESUMO

The number of published literature on the effect of ultrasonic cavitation and advanced oxidation pretreatment on the dewatering performance of anaerobically digested sludge is very limited. This study aims at determining the optimum operating conditions of large-scale filtering centrifuges in wastewater treatment plants. The optimum dose of hydrogen peroxide, ultrasonic power, ultrasonic duration, ultrasonic pulse and particle size distribution for improved dewatering performance were determined in this study. In addition, shear stress-shear rate and viscosity-shear rate rheograms were developed to show the rheological flow properties for varying ultrasonic power and treatment duration. Optimum sonication power, time, pulse and amplitude were determined to be 14 W, 1 min, 55/5 and 20%, respectively. At a pH of 6.8, the optimum concentration of hydrogen peroxide was found to be 43.5 g/L. The optimum hydrogen peroxide dose in the combined conditioning experiments was determined to be 500 mg/L at a pH of 3. Under these optimum conditions, capillary suction time was reduced significantly by 71.1%. This study helps to reduce polymer consumption and provides the optimum pretreatment and dewatering operating conditions, and better monitoring and control in the dewatering unit has significant impact in the overall economy of wastewater treatment plants.


Assuntos
Peróxido de Hidrogênio , Oxirredução , Esgotos , Eliminação de Resíduos Líquidos , Esgotos/química , Peróxido de Hidrogênio/química , Eliminação de Resíduos Líquidos/métodos , Ultrassom/métodos , Concentração de Íons de Hidrogênio
2.
Food Res Int ; 188: 114502, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823845

RESUMO

Lycium barbarum L. berries have a remarkable chemical composition and extensive biological activities, being a valuable component of health and nutraceutical practices. Nevertheless, a deep insight on the intestinal permeation of the pro-healthy bioactive compounds is urgently needed to predict the real effects on human body. This study attempted, for the first time, to optimize the Ultrasound-Assisted Extraction (UAE) of goji berries using a Response Surface Methodology approach and establish the intestinal permeation of the principal pro-healthy compounds. The optimal extraction conditions were a solid:liquid ratio of 8.75 % for 56.21 min, using an intensity of 59.05 W/m2. The optimal extract displayed a remarkable antioxidant capacity, with LC/DAD-ESI-MS analysis unveiled a diverse phytochemical profile, encompassing different compounds (e.g. glu-lycibarbarspermidine F, 2-glu-kukoamine, rutin, 3,5-dicaffeoylquinic acid). The intestinal co-culture model demonstrated that glu-lycibarbarspermidine F (isomer 2) (73.70 %), 3,5-dicaffeoylquinic acid (52.66 %), and isorhamnetin-3-O-rutinoside (49.31 %) traversed the intestinal cell layer, exerting beneficial health-promoting effects.


Assuntos
Antioxidantes , Frutas , Lycium , Extratos Vegetais , Lycium/química , Frutas/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Humanos , Permeabilidade , Ondas Ultrassônicas , Compostos Fitoquímicos/isolamento & purificação , Mucosa Intestinal/metabolismo , Células CACO-2 , Absorção Intestinal , Rutina/isolamento & purificação , Ultrassom/métodos , Função da Barreira Intestinal
3.
Food Res Int ; 188: 114493, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823876

RESUMO

In this paper, two emulsion systems with high and low solid fat contents were prepared from 20 % water phase and 80 % oil phase by adjusting the palm oil/palm stearin/soybean oil ratio. Different ultrasonic power and time were used for the pretreatment of emulsion with different solid fat content, and the application characteristics of ultrasonic in W/O emulsions were explored and evaluated. Directly using high-intensity ultrasound to prepare fatty emulsions would weaken the hardness and storage modulus G' of the samples. Although ultrasound reduced the size of fat crystals in emulsions, the interaction between water droplets and fat crystals needs to be considered. After ultrasonic treatment, water droplets were difficult to immobilize on the crystal surface and thus acted as an active filler to stabilize the emulsion together with the fat crystal network. In high solid fat emulsion systems, an increase in ultrasound power (from 100 W to 200 W) could more affect the crystallization behavior of fats than an increase in ultrasound duration (from 30 s to 60 s), and the distribution of crystals and droplets was more uniform. In the low solid fat emulsion system, the texture of the sample after ultrasonic treatment was softer, and the surface was more delicate and smoother. However, the higher ultrasonic intensity (200 W) was not conducive to the preparation of the spread. Although the ultrasound with excessive intensity promoted the formation of small crystals, it would also lead to the aggregation of small crystals. These small crystals cannot form a uniform crystal network, which increases the fluidity of emulsions.


Assuntos
Cristalização , Emulsões , Óleo de Palmeira , Tamanho da Partícula , Água , Emulsões/química , Água/química , Óleo de Palmeira/química , Óleo de Soja/química , Ondas Ultrassônicas , Ultrassom
4.
J Microorg Control ; 29(2): 75-80, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38880619

RESUMO

When a hypochlorite solution is ultrasonically fogged in a room, free chlorine, i.e., HOCl and OCl-, reaches various positions in two forms: fine fog droplets and gaseous hypochlorous acid(HOCl(g)). In this study, the cumulative amount of free chlorine reaching various positions on the floor away from the fogger was measured in a 90-m3 room, using a sulfamate-carrying glass-fiber filter indicator. The fine droplets were blown out from the fogger into the spaces at different discharge port angles of 30 - 90°. Free chlorine was successfully trapped by sulfamate, forming monochlorosulfamate, which was stably retained on the indicator. The cumulative amount of free chlorine( ng/indicator) increased with fogging time at each position and depended on the blow angle and distance from the fogger. Minor differences in the HOCl(g) concentration near the floor at all positions were observed. The disinfection efficacy of the fogging treatment against Staphylococcus aureus on wet surfaces was relatively higher at positions near the fogger and lower at positions far from the fogger. At each discharge port angle, a strong correlation between the logarithmic reduction in relative viable cells and the cumulative amount of free chlorine reaching S. aureus plates was observed. The slopes of the regression lines of correlation diagrams as a function of the cumulative amount of free chlorine were between -0.0362 and -0.0413 ng-1. This study demonstrated that the cumulative amount of free chlorine measured using the filter indicator could reflect the sum of the free chlorine of both fine droplets and HOCl(g), and that the disinfection efficiency depended on the cumulative amount of free chlorine reaching different areas.


Assuntos
Cloro , Desinfetantes , Desinfecção , Ácido Hipocloroso , Staphylococcus aureus , Cloro/farmacologia , Cloro/química , Desinfecção/métodos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Ácido Hipocloroso/farmacologia , Ácido Hipocloroso/química , Desinfetantes/farmacologia , Desinfetantes/química , Ultrassom
5.
PLoS One ; 19(5): e0302585, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38820449

RESUMO

The article is devoted to investigation of energy-efficient moisture removal from capillary-porous materials. Moisture is removed by dispersion at collapse of cylindrical cavitation bubbles, formed by ultrasonic vibrations in the capillaries of the material. Mathematical model, which allowed to investigate the mechanism of moisture dispersion, has been developed. Necessity of realization of cavitation bubble full life cycle in capillary (slow growth, rapid expansion with deformation, collapse) was found. An optimal range of sound pressure levels from 150 dB ("critical level" at which dispersion of water from capillary starts) up to 170 dB (dispersion productivity growth stops due to cavitation bubbles reaching maximum size equal to diameter of capillary) was determined. It is shown that the size of the dewatered sample for maximum drying efficiency should correspond to the ultrasonic wavelength in air. Ultrasonic dispersion of liquid during drying was confirmed experimentally. It is found that for significant reduction of drying time (up to 50% and more) it is necessary to affect in the range of 165-170 dB. And the materials to be dried must be placed as particles or layers having dimensions or thicknesses corresponding to the length of the ultrasonic wave in air. The implementation of ultrasonic drying, on the example of food products (beets) provided a reduction in drying time of 1.9 times, while reducing energy costs by 1.7 times in comparison with convective drying.


Assuntos
Água , Água/química , Dessecação/métodos , Simulação por Computador , Ultrassom/métodos , Modelos Teóricos , Ondas Ultrassônicas , Porosidade
6.
Food Chem ; 452: 139561, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38728897

RESUMO

The utilization of essential oils as natural antioxidants and preservatives is limited by high volatility, poor water solubility, and long-term instability. To address this, a novel ultrasonic-assisted method was used to prepare and stabilize a nanoemulsion of turmeric essential oil-in-water, incorporating bioactive components extracted from Spirulina platensis. Ultrasonic treatment enhanced the extraction efficacy and nanoemulsion stability. Algal biomass subjected to ultrasonic treatment (30 min at 80% amplitude) yielded a dry extract of 73.66 ± 3.05%, with the highest protein, phenolic, phycocyanin, and allophycocyanin content, as well as maximum emulsifying activity. The resulting nanoemulsion (5% oil, 0.3% extract, 10 min ultrasonic treatment) showed reduced particle size (173.31 ± 2.24 nm), zeta potential (-36.33 ± 1.10 mV), low polydispersity index, and enhanced antioxidant and antibacterial properties. Rheology analysis indicated shear-thinning behavior, while microscopy and spectroscopy confirmed structural changes induced by ultrasonic treatment and extract concentration. This initiative developed a novel ultrasonic-assisted algal-based nanoemulsion with antioxidant and antibacterial properties.


Assuntos
Antibacterianos , Antioxidantes , Curcuma , Emulsões , Óleos Voláteis , Spirulina , Spirulina/química , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Emulsões/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Curcuma/química , Antibacterianos/farmacologia , Antibacterianos/química , Química Verde , Ultrassom , Tamanho da Partícula , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/isolamento & purificação , Água/química
7.
Food Res Int ; 187: 114354, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763639

RESUMO

Carotenoids, versatile natural pigments with numerous health benefits, face environmental concerns associated with conventional petrochemical-based extraction methods and limitations of their synthetic equivalents. In this context, this study aims to introduce eco-friendly approaches using ultrasound-based strategies (probe and bath) for the extraction of carotenoids from microalgae, initially focusing on Microchloropsis gaditana and subsequently evaluating the versatility of the method by applying it to other microalgae species of interest (Tisochrysis lutea, Porphyridium cruentum, and Phaeodactylum tricornutum) and defatted microalgal residues. Among the approaches evaluated, the 5-min ultrasonic probe system with ethanol showed comparable carotenoid recovery efficiency to the reference method (agitation, 24 h, acetone) (9.4 ± 2.5 and 9.6 ± 3.2 mg g-1 carotenoids per dry biomass, for the green and the reference method, respectively). Moreover, the method's sustainability was demonstrated using the AGREEprep™ software (scored 0.62 out of 1), compared to the traditional method (0.22 out of 1). The developed method yielded high carotenoid contents across species with diverse cell wall compositions (3.1 ± 0.2, 2.1 ± 0.3, and 4.1 ± 0.1 mg g-1 carotenoid per dry biomass for T. lutea, P. cruentum, and P. tricornutum, respectively). Moreover, the application of the method to defatted biomass showed potential for microalgal valorization with carotenoid recovery rates of 41 %, 60 %, 61 %, and 100 % for M.gaditana, P. tricornutum, T. lutea, and P. cruentum, compared to the original biomass, respectively. Furthermore, by using high-performance liquid chromatography with a diode array detector (HPLC-DAD) and high-resolution mass spectrometry (HRMS), we reported the carotenoid and chlorophyll profiles of the different microalgae and evaluated the impact of the eco-friendly methods. The carotenoid and chlorophyll profiles varied depending on the species, biomass, and method used. In summary, this study advances a green extraction method with improved environmental sustainability and shorter extraction time, underscoring the potential of this approach as a valuable alternative for the extraction of microalgal pigments.


Assuntos
Carotenoides , Microalgas , Carotenoides/análise , Carotenoides/isolamento & purificação , Microalgas/química , Espectrometria de Massas , Ultrassom/métodos , Biomassa , Química Verde
8.
Pak J Pharm Sci ; 37(2): 265-274, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38767093

RESUMO

An innovative ultrasonic-assisted enzymatic aqueous two-phase extraction (UAE-ATPE) method was applied to enhance the yield from Strobilanthes crispus leaves, exploring both sequential and simultaneous approaches. Comparative analysis included assessing total phenolic content (TPC), total flavonoid content (TFC), partition coefficient (k) and recovery (R). Liquid chromatography-mass spectrometry and scanning electron microscopy evaluated extracts from both techniques. Simultaneous UAE-ATPE demonstrated significantly higher TPC (5.7±0.1 mg GAE/g dry leaves) and TFC (3.3±0.1 mg QE/g dry leaves) compared to sequential extraction, where TPC and TFC measured 4.5±0.3 mg GAE/g dry leaves and 1.7±0.1 mg QE/g dry leaves. Additionally, simultaneous UAE-ATPE yielded higher k and R values for phenolic and flavonoid compounds. Notably, it identified 32.4% of the area corresponding to 6 compounds, surpassing the 25.3% area identified sequentially with 13 compounds. A collaborative effect of enzymatic hydrolysis and ultrasonic extraction was observed in simultaneous UAE-ATPE. In the inhibition test on the HMG-CoA reductase enzyme, simultaneous UAE-ATPE extract (200 µg/mL) exhibited exceptional results, achieving superior inhibition of 66.1% compared to the sequential method's inhibition of 39.4%. This underscores the efficacy of simultaneous UAE-ATPE in producing concentrated anti-cholesterol compounds. The study strongly emphasizes the superiority of simultaneous UAE-ATPE over the sequential approach.


Assuntos
Flavonoides , Extratos Vegetais , Folhas de Planta , Folhas de Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Flavonoides/isolamento & purificação , Flavonoides/análise , Fenóis/análise , Fenóis/isolamento & purificação , Fenóis/química , Ultrassom/métodos
9.
Chemosphere ; 360: 142420, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38795914

RESUMO

The ubiquitousness of per- and polyfluoroalkyl substances (PFAS) is a big concern and PFAS remediation is urgently needed such as via degradation. While previous studies have explored ultrasonic degradation of PFAS, work evaluating the operational parameters is rare, especially concerning real wastes such as aqueous film-forming foam (AFFF) and foam fractionate (FF). This study investigates the key operational parameters affecting the degradation efficiency of PFAS, encompassing ultrasonication frequency (580-1144 kHz), power intensity (125-187.5 W), initial concentration (0.08-40 ppm), treatment duration (0.5-3 h), sample volume (100-500 mL), and PFAS structure (perfluorooctanoic acid or PFOA; perfluorooctane sulfonate or PFOS; 6:2 fluorotelomer sulfonate or 6:2 FTS). The defluorination kinetics is different from the removal/degradation kinetics due to the generation of degradation intermediates, suggesting the complex degradation mechanism, which should be evaluated to close the mass balance effectively. Notably, the optimised ultrasonic system achieves ∼125%/∼115% defluorination in AFFF/FF example wastes (compared to ∼65%/∼97% removal) despite their complex composition and the involvement of total oxidizable precursor (TOP) assay. In the meantime, a few new PFAS are detected in the post-treatments, including perfluorohexane sulfonic acid (PFHxS) and 10:2 fluorotelomer sulfonate (10:2 FTS) in the AFFF, and perfluorooctane sulfonamide (FOSA) and 8:2 fluorotelomer sulfonate (8:2 FTS) in the FF, again suggesting the complex degradation mechanism. Overall, ultrasonication is effective to degrade PFAS real example wastes, advancing its potential for scale-up applications.


Assuntos
Ácidos Alcanossulfônicos , Caprilatos , Fluorocarbonos , Poluentes Químicos da Água , Fluorocarbonos/química , Ácidos Alcanossulfônicos/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Caprilatos/química , Cinética , Ondas Ultrassônicas , Ultrassom , Recuperação e Remediação Ambiental/métodos
10.
Int J Pharm ; 657: 124177, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38697582

RESUMO

We present a promising method for producing amorphous drug particles using a nozzle-free ultrasonic nebulizer with polymers, specifically polyvinylpyrrolidone (PVP), poly(acrylic acid) (PAA), and Eudragit® S 100 (EUD). Model crystalline phase drugs-Empagliflozin, Furosemide, and Ilaprazole-are selected. This technique efficiently produces spherical polymer-drug composite particles and demonstrates enhanced stability against humidity and thermal conditions, compared to the drug-only amorphous particles. The composite particles exhibit improved water dissolution compared to the original crystalline drugs, indicating potential bioavailability enhancements. While there are challenges, including the need for continuous water supply for ultrasonic component cooling, dependency on the solubility of polymers and drugs in volatile organic solvents, and mildly elevated temperatures for solvent evaporation, our method offers significant advantages over traditional approaches. It provides a straightforward, flexible process adaptable to various drug-polymer combinations and consistently yields spherical amorphous solid dispersion (ASD) particles with a narrow size distribution. These attributes make our method a valuable advancement in pharmaceutical drug formulation and delivery.


Assuntos
Nebulizadores e Vaporizadores , Tamanho da Partícula , Polímeros , Polímeros/química , Estabilidade de Medicamentos , Solubilidade , Composição de Medicamentos/métodos , Resinas Acrílicas/química , Povidona/química , Ultrassom , Ácidos Polimetacrílicos/química , Furosemida/química , Química Farmacêutica/métodos
11.
Food Chem ; 451: 139500, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38696941

RESUMO

Deep eutectic solvent (DES) combined with ultrasonic-assisted extraction was employed as an environmentally friendly technique for extracting antioxidant phenolic compounds from Neem leaves in place of organic solvents. Choline chloride-Ethylene glycol (1:2) with 40% V/V water content (DES-1) was investigated as a potential total phenolic content extractant (38.2 ± 1.2 mg GAE/g DW, where GAE: gallic acid equivalent, DW: dry weight). The optimal operational parameters assessed using single-factor experiments to maximize the total phenolic compounds content were as follows: extraction time of 30 min, 40% V/V water content, liquid-solid ratio of 15:1, and room temperature. Additionally, the in-vitro antioxidant experiments (2,2-diphenyl-1- picrylhydrazyl radical scavenging assay and ferric reducing antioxidant power assay) demonstrated the DES-1-based extract of Neem leaves as a potent antioxidant agent, compared to traditional solvents. Moreover, microscopic morphological analysis supported the effectiveness of DES-1 for the noticeable alteration in the fiber surface structure of Neem leaves after extraction which benefited in the release of polyphenols from these leaves. Eventually, the mass analysis of the extract disclosed the presence of eleven polyphenols in the extract. The Green Analytical Procedure Index revealed the greenness of the extraction method.


Assuntos
Antioxidantes , Solventes Eutéticos Profundos , Química Verde , Fenóis , Extratos Vegetais , Folhas de Planta , Folhas de Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Fenóis/química , Fenóis/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Solventes Eutéticos Profundos/química , Azadirachta/química , Fracionamento Químico/métodos , Ultrassom , Solventes/química
12.
Sci Rep ; 14(1): 10438, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714704

RESUMO

Thrombus formation in extracorporeal membrane oxygenation (ECMO) remains a major concern as it can lead to fatal outcomes. To the best of our knowledge, there is no standard non-invasive method for quantitatively measuring thrombi. This study's purpose was to verify thrombus detection in an ECMO circuit using novel, non-invasive ultrasonic sensors in real-time, utilizing the fact that the ultrasonic velocity in a thrombus is known to be higher than that in the blood. Ultrasonic sensors with a customized chamber, an ultrasonic pulse-receiver, and a digital storage oscilloscope (DSO) were used to set up the measuring unit. The customized chamber was connected to an ECMO circuit primed with porcine blood. Thrombi formed from static porcine blood were placed in the circuit and ultrasonic signals were extracted from the oscilloscope at various ECMO flow rates of 1-4 L/min. The ultrasonic signal changes were successfully detected at each flow rate on the DSO. The ultrasonic pulse signal shifted leftward when a thrombus passed between the two ultrasonic sensors and was easily detected on the DSO screen. This novel real-time non-invasive thrombus detection method may enable the early detection of floating thrombi in the ECMO system and early management of ECMO thrombi.


Assuntos
Oxigenação por Membrana Extracorpórea , Trombose , Oxigenação por Membrana Extracorpórea/métodos , Oxigenação por Membrana Extracorpórea/instrumentação , Trombose/diagnóstico por imagem , Trombose/diagnóstico , Animais , Suínos , Ultrassom , Ultrassonografia/métodos
13.
Sensors (Basel) ; 24(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38732843

RESUMO

As the number of electronic gadgets in our daily lives is increasing and most of them require some kind of human interaction, this demands innovative, convenient input methods. There are limitations to state-of-the-art (SotA) ultrasound-based hand gesture recognition (HGR) systems in terms of robustness and accuracy. This research presents a novel machine learning (ML)-based end-to-end solution for hand gesture recognition with low-cost micro-electromechanical (MEMS) system ultrasonic transducers. In contrast to prior methods, our ML model processes the raw echo samples directly instead of using pre-processed data. Consequently, the processing flow presented in this work leaves it to the ML model to extract the important information from the echo data. The success of this approach is demonstrated as follows. Four MEMS ultrasonic transducers are placed in three different geometrical arrangements. For each arrangement, different types of ML models are optimized and benchmarked on datasets acquired with the presented custom hardware (HW): convolutional neural networks (CNNs), gated recurrent units (GRUs), long short-term memory (LSTM), vision transformer (ViT), and cross-attention multi-scale vision transformer (CrossViT). The three last-mentioned ML models reached more than 88% accuracy. The most important innovation described in this research paper is that we were able to demonstrate that little pre-processing is necessary to obtain high accuracy in ultrasonic HGR for several arrangements of cost-effective and low-power MEMS ultrasonic transducer arrays. Even the computationally intensive Fourier transform can be omitted. The presented approach is further compared to HGR systems using other sensor types such as vision, WiFi, radar, and state-of-the-art ultrasound-based HGR systems. Direct processing of the sensor signals by a compact model makes ultrasonic hand gesture recognition a true low-cost and power-efficient input method.


Assuntos
Gestos , Mãos , Aprendizado de Máquina , Redes Neurais de Computação , Humanos , Mãos/fisiologia , Reconhecimento Automatizado de Padrão/métodos , Ultrassonografia/métodos , Ultrassonografia/instrumentação , Ultrassom/instrumentação , Algoritmos
14.
An Acad Bras Cienc ; 96(2): e20230840, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747838

RESUMO

The extraction of valuable compounds from dried fruits and vegetables by microwave hydrodiffusion and gravity (MHG) requires previous hydration of the plant material. In this work, ultrasound was used to speed up the hydration of guarana powder before MHG extraction and increase caffeine recovery. The humidification step was speeded up with ultrasound taking only 15 min over 60 min without ultrasound. Water and 50% (v/v) ethanol were evaluated as green solvents for humidification, with a higher concentration of caffeine obtained for the hydroalcoholic solution. Ultrasound pretreatment allowed guarana extracts from MHG with two times more caffeine for both solvents evaluated. Therefore, ultrasound can be used in the hydration step before MHG extraction to reduce time and increase caffeine recovery from guarana powder.


Assuntos
Cafeína , Micro-Ondas , Paullinia , Extratos Vegetais , Pós , Cafeína/análise , Cafeína/isolamento & purificação , Paullinia/química , Extratos Vegetais/química , Gravitação , Ultrassom , Solventes
15.
Food Res Int ; 183: 114212, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38760140

RESUMO

This study evaluated the effect of ultrasound treatment combined or not with heat treatment applied to lentil protein isolate (LPI) aiming to enhance its ability to stabilize high internal phase emulsions (HIPE). LPI dispersion (2%, w/w) was ultrasound-treated at 60% (UA) and 70% (UB) amplitude for 7 min; these samples were subjected to and then heat treatments at 70 °C (UAT70 and UBT70, respectively) or 80 °C (UAT80 and UBT80, respectively) for 20 min. HIPEs were produced with 25% untreated and treated LPI dispersions and 75% soybean oil using a rotor-stator (15,500 rpm/1 min). The LPI dispersions were evaluated for particle size, solubility, differential scanning calorimetry, electrophoresis, secondary structure estimation (circular dichroism and FT-IR), intrinsic fluorescence, surface hydrophobicity, and free sulfhydryl groups content. The HIPEs were evaluated for droplet size, morphology, rheology, centrifugal stability, and the Turbiscan test. Ultrasound treatment decreased LPI dispersions' particle size (∼80%) and increased solubility (∼90%). Intrinsic fluorescence and surface hydrophobicity confirmed LPI modification due to the exposure to hydrophobic patches. The combination of ultrasound and heat treatments resulted in a reduction in the free sulfhydryl group content of LPI. HIPEs produced with ultrasound-heat-treated LPI had a lower droplet size distribution mode, greater oil retention values in the HIPE structure (> 98%), lower Turbiscan stability index (< 2), and a firmer and more homogeneous appearance compared to HIPE produced with untreated LPI, indicating higher stability for the HIPEs stabilized by treated LPI. Therefore, combining ultrasound and heat treatments could be an effective method for the functional modification of lentil proteins, allowing their application as HIPE emulsifiers.


Assuntos
Emulsões , Temperatura Alta , Lens (Planta) , Tamanho da Partícula , Proteínas de Plantas , Lens (Planta)/química , Emulsões/química , Proteínas de Plantas/química , Solubilidade , Interações Hidrofóbicas e Hidrofílicas , Manipulação de Alimentos/métodos , Varredura Diferencial de Calorimetria , Espectroscopia de Infravermelho com Transformada de Fourier , Dicroísmo Circular , Reologia , Ultrassom/métodos , Sonicação/métodos
16.
J Pharm Sci ; 113(7): 2001-2003, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38642708

RESUMO

High-pressure homogenization is a widely used and acknowledged method to reduce the particle sizes of active pharmaceutical compounds into nanosized range. Thus, the method is associated with limitations, as the compound's initial particle size, since micronized particles are often prerequired to achieve successful size reduction into nanosized range. In this work, the usage of ultrasound as a potential milling or pre-milling technique to decrease particle sizes of different drug compounds varying in deformation properties into micronized range, was investigated.


Assuntos
Composição de Medicamentos , Tamanho da Partícula , Suspensões , Composição de Medicamentos/métodos , Nanopartículas/química , Água/química , Ultrassom/métodos , Preparações Farmacêuticas/química , Sonicação/métodos , Química Farmacêutica/métodos , Pressão
17.
BMC Oral Health ; 24(1): 417, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580933

RESUMO

BACKGROUND: Many instruments used in dentistry are rotary, such as handpieces, water syringes, and ultrasonic scalers that produce aerosols. The spray created by these instruments can carry, in addition to water, droplets of saliva, blood, and microorganisms, which can pose a risk of infections for healthcare professionals and patients. Due to the COVID-19 pandemic, this gained attention. OBJECTIVE: The aim was to carry out a systematic review of the evidence of the scope of the aerosol produced by ultrasonic scaler in environmental contamination and the influence of the use of intraoral suction reduction devices. DESIGN: Scientific literature was searched until June 19, 2021 in 6 databases: Pubmed, EMBASE, Web of science, Scopus, Virtual Health Library and Cochrane Library, without restrictions on language or publication date. Studies that evaluated the range of the aerosol produced by ultrasonic scaler during scaling/prophylaxis and the control of environmental contamination generated by it with the use of low (LVE) and high (HVE) volume evacuation systems were included. RESULTS: Of the 1893 potentially relevant articles, 5 of which were randomized controlled trials (RCTs). The meta-analysis of 3 RCTs showed that, even at different distances from the patient's oral cavity, there was a significant increase in airborne bacteria in the dental environment with the use of ultrasonic scaler. In contrast, when meta-analysis compared the use of HVE with LVE, there was no significant difference (P = 0.40/CI -0.71[-2.37, 0.95]) for aerosol produced in the environment. CONCLUSIONS: There is an increase in the concentration of bioaerosol in the dental environment during the use of ultrasonic scaler in scaling/prophylaxis, reaching up to 2 m away from the patient's mouth and the use of LVE, HVE or a combination of different devices, can be effective in reducing air contamination in the dental environment, with no important difference between different types of suction devices.


Assuntos
Terapia por Ultrassom , Humanos , Ultrassom , Aerossóis e Gotículas Respiratórios , Aerossóis/efeitos adversos , Água , Raspagem Dentária
18.
Med Eng Phys ; 126: 104129, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38621834

RESUMO

3D printed Poly Lactic Acid (PLA) bone plates exhibit limited three-point bending strength, restricting their viability in biomedical applications. The application of polydopamine (PDM) enhances the three-point bending strength by undergoing covalent interactions with PLA molecular structure. However, the heavy nature of PDM particles leads to settling at the container base at higher coating solution concentrations. This study investigates the impact of ultrasonic-assisted coating parameters on the three-point bending strength. Utilizing Response Surface Methodology (RSM) for statistical modeling, the study examines the influence of ultrasonic vibration power (UP), coating solution concentration (CC), and submersion time (TIME). RSM optimization recommended 100 % UP, 6 mg/ml CC, and 150 min TIME, resulting in maximum three-point bending strength of 83.295 MPa. Microscopic images from the comparative analysis revealed non-uniform coating deposition with mean thickness of 6.153 µm under normal coating. In contrast, ultrasonic-assisted coating promoted uniform deposition with mean thickness of 18.05 µm. The results demonstrate that ultrasonic-assisted coating induces PDM particle collision, preventing settling at the container base, and enhances three-point bending strength by 7.27 % to 23.24 % compared to the normal coating condition. This study emphasizes on the potential of ultrasonic-assisted coating to overcome the limitations of direct immersion coating technique.


Assuntos
Placas Ósseas , Ultrassom , Poliésteres/química , Ondas Ultrassônicas , Impressão Tridimensional
19.
Water Sci Technol ; 89(7): 1630-1646, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619894

RESUMO

Due to the colloidal stability, the high compressibility and the high hydration of extracellular polymeric substances (EPS), it is difficult to efficiently dehydrate sludge. In order to enhance sludge dewatering, the process of ultrasonic (US) cracking, chitosan (CTS) re-flocculation and sludge-based biochar (SBB) skeleton adsorption of water-holding substances to regulate sludge dewaterability was proposed. Based on the response surface method, the prediction model of the specific resistance to filtration (SRF) and sludge cake moisture content (MC) was established. The US cracking time and the dosage of CTS and SBB were optimized. The results showed that the optimal parameters of the three were 5.08 s, 10.1 mg/g dry solids (DS) and 0.477 g/g DS, respectively. Meantime, the SRF and MC were 5.4125 × 1011 m/kg and 76.8123%, which significantly improved the sludge dewaterability. According to the variance analysis, it is found that the fitting degree of SRF and MC model is good, which also confirms that there is significant interaction and synergy between US, CTS and SBB, and the contribution of CTS and SBB is greater. Moreover, the process significantly improves the sludge's calorific value and makes its combustion more durable.


Assuntos
Quitosana , Esgotos , Ultrassom , Carvão Vegetal , Filtração , Água , Eliminação de Resíduos Líquidos/métodos
20.
Environ Sci Pollut Res Int ; 31(20): 30085-30098, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38598155

RESUMO

Formaldehyde (HCHO) is one of the primary indoor air pollutants, and efficiently eliminating it, especially at low concentrations, remains challenging. In this study, BiVO4-TiO2 catalyst was developed using ultrasonic blending technology for the photocatalytic oxidation of low-level indoor HCHO. The crystal structure, surface morphology, element distribution, and active oxidation species of the catalyst were examined using XRD, SEM, TEM, UV-Vis, EDS, and ESR techniques. Our results demonstrated that the BiVO4-TiO2 catalyst, prepared by ultrasonic blending, exhibited good oxidation performance and stability. The HCHO concentration reduced from 1.050 to 0.030 mg/m3 within 48 h, achieving a removal rate of 97.1%. The synergy between BiVO4 and TiO2 enhanced the efficiency of separating photogenerated carriers and minimized the likelihood of recombination between photogenerated electrons and holes. Additionally, this synergy significantly enhanced the presence of hydroxyl radicals (·OH) on the catalyst, resulting in an oxidation performance superior to that of either BiVO4 or TiO2. Our research offers valuable insights for the development of new photocatalysts to address HCHO pollution.


Assuntos
Bismuto , Formaldeído , Oxirredução , Titânio , Vanadatos , Formaldeído/química , Titânio/química , Vanadatos/química , Bismuto/química , Catálise , Luz , Ultrassom
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