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1.
Ultrason Sonochem ; 77: 105700, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34364068

RESUMO

In this study, microcapsules were prepared by spray drying and embedding hemp seed oil (HSO) with soy protein isolate (SPI) and maltodextrin (MD) as wall materials. The effect of ultrasonic power on the microstructure and characteristics of the composite emulsion and microcapsules was studied. Studies have shown that ultrasonic power has a significant impact on the stability of composite emulsions. The particle size of the composite emulsion after 450 W ultrasonic treatment was significantly lower than the particle size of the emulsion without the ultrasonic treatment. Through fluorescence microscopy observation, HSO was found to be successfully embedded in the wall materials to form an oil/water (O/W) composite emulsion. The spray-dried microcapsules showed a smooth spherical structure through scanning electron microscopy (SEM), and the particle size was 10.7 µm at 450 W. Fourier transform infrared (FTIR) spectroscopy analysis found that ultrasonic treatment would increase the degree of covalent bonding of the SPI-MD complex to a certain extent, thereby improving the stability and embedding effect of the microcapsules. Finally, oxidation kinetics models of HSO and HSO microcapsules were constructed and verified. The zero-order model of HSO microcapsules was found to have a higher degree of fit; after verification, the model can better reflect the quality changes of HSO microcapsules during storage.


Assuntos
Cannabis/química , Modelos Químicos , Extratos Vegetais/química , Polissacarídeos/química , Proteínas de Soja/química , Ondas Ultrassônicas , Cápsulas , Cinética , Oxirredução
2.
Ultrason Sonochem ; 77: 105685, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34364069

RESUMO

Protein oxidation leads to covalent modification of structure and deterioration of functional properties of quinoa protein. The objective of this study was to investigate the effects of ultrasonic treatment on the functional and physicochemical properties of quinoa protein oxidation aggregates. In this concern, 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) was selected as oxidative modification of quinoa protein. The microstructure of quinoa protein displayed by scanning electron microscope (SEM) indicated that oxidation induced extensive aggregation, leading to carbonylation and degradation of sulfhydryl groups. Aggregation induced by oxidation had a negative effect on the solubility, turbidity, emulsifying stability. However, according to the analysis of physicochemical properties, ultrasonic significantly improved the water solubility of quinoa protein. The quinoa protein treated by ultrasonic for 30 min exhibited the best dispersion stability in water, which corresponded to the highest ζ-potential, smallest particle size and most uniform distribution. Based on the FT-IR, SDS-PAGE and surface hydrophobicity analysis, the increase of α-helix, ß-turn and surface hydrophobicity caused by cavitation effect appeared to be the main mechanism of quinoa protein solubilization. In addition, the hydrophobic region of the protein was re-buried by excessive ultrasonic treatment, and the protein molecules were reaggregated by disulfide bonds. Microstructural observations further confirmed that ultrasonic treatment effectively inhibited protein aggregation and improved the functional properties of quinoa protein.


Assuntos
Chenopodium quinoa/química , Proteínas de Plantas/química , Agregados Proteicos , Ondas Ultrassônicas , Amidinas/química , Qualidade dos Alimentos , Oxirredução
3.
Ultrason Sonochem ; 77: 105680, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34365154

RESUMO

The present study optimised the ultrasound-assisted extraction (UAE) of bioactive compounds from Amaranthus hypochondriacus var. Nutrisol. Influence of temperature (25.86-54.14 °C) and ultrasonic power densities (UPD) (76.01-273.99 mW/mL) on total betalains (BT), betacyanins (BC), betaxanthins (BX), total polyphenols (TP), antioxidant activity (AA), colour parameters (L*, a*, and b*), amaranthine (A), and isoamaranthine (IA) were evaluated using response surface methodology. Moreover, betalain extraction kinetics and mass transfer coefficients (KLa) were determined for each experimental condition. BT, BC, BX, TP, AA, b*, KLa, and A were significantly affected (p < 0.05) by temperature extraction and UPD, whereas L*, a*, and IA were only affected (p < 0.05) by temperature. All response models were significantly validated with regression coefficients (R2) ranging from 87.46 to 99.29%. BT, A, IA, and KLa in UAE were 1.38, 1.65, 1.50, and 29.93 times higher than determined using conventional extraction, respectively. Optimal UAE conditions were obtained at 41.80 °C and 188.84 mW/mL using the desired function methodology. Under these conditions, the experimental values for BC, BX, BT, TP, AA, L*, a*, b*, KLa, A, and IA were closely related to the predicted values, indicating the suitability of the developed quadratic models. This study proposes a simple and efficient UAE method to obtain betalains and polyphenols with high antioxidant activity, which can be used in several applications within the food industry.


Assuntos
Amaranthus/química , Antioxidantes/isolamento & purificação , Betalaínas/isolamento & purificação , Fracionamento Químico/métodos , Polifenóis/isolamento & purificação , Ondas Ultrassônicas , Fatores de Tempo
4.
Ultrason Sonochem ; 77: 105702, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34375945

RESUMO

2-picoline is a very important pyridine derivative with significant applications though it is also poisonous and harmful having considerable adverse influence on aquatic life, environment and organisms. The need for developing effective treatment methodologies for 2-Picoline directed the current work focusing on degradation of 2-Picoline using the combination of ultrasound and advanced oxidants such as hydrogen peroxide (H2O2), potassium persulphate (KPS), Fenton's reagent, and Peroxymonosulphate (PMS) along with the use of Titanium oxide (TiO2) as catalyst. Ultrasonic bath having 8 L capacity and operating frequency of 40 ± 2 kHz has been used. The effect of parameters like power, initial pH, temperature, time and initial concentration of 2-Picoline were studied to establish best operating conditions which were further used in the combination treatment approaches of ultrasound with oxidising agents. The chemical oxygen demand (COD) reduction for the optimized approaches of ultrasound in combination with oxidizing agents was also determined. Degradation experiments were performed using oxidising agents also in absence of ultrasound to investigate the individual treatment capacity of the oxidants and also the synergetic index for the combination. Kinetic study demonstrated that second order model suited for all the treatment approaches except US/Fenton where first order model fitted better. Ultrasound in combination with Fenton reagent demonstrated a substantial synergy for the degradation of 2-Picoline compared to other treatment approaches showing highest degradation of 97.6 %, synergetic index as 5.71, cavitational yield of 1.82 × 10-5 mg/J and COD removal of 82.4 %.


Assuntos
Oxidantes/química , Picolinas/química , Ondas Ultrassônicas , Concentração de Íons de Hidrogênio , Cinética , Temperatura
5.
Sensors (Basel) ; 21(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34450940

RESUMO

In this paper, the possibility of using nonlinear ultrasonic guided waves for early-life material degradation in metal plates is investigated through both computational modeling and study. The analysis of the second harmonics of Lamb waves in a free boundary aluminum plate, and the internal resonance conditions between the Lamb wave primary modes and the second harmonics are investigated. Subsequently, Murnaghan's hyperelastic model is implemented in a finite element (FE) analysis to study the response of aluminum plates subjected to a 60 kHz Hanning-windowed tone burst. Different stages of material degradation are reflected as the changes in the third order elastic constants (TOECs) of the Murnaghan's model. The reconstructed degradations match the actual ones well across various degrees of degradation. The effects of several relevant factors on the accuracy of reconstructions are also discussed.


Assuntos
Ondas Ultrassônicas , Vibração , Animais , Simulação por Computador , Análise de Elementos Finitos , Ovinos , Tomografia
6.
Angle Orthod ; 91(5): 619-625, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34407180

RESUMO

OBJECTIVE: To assess the efficiency of low-intensity pulsed ultrasound (LIPUS) and photobiomodulation (PBM) interventions in accelerating orthodontic tooth movement during clear aligner therapy (CAT). MATERIALS AND METHODS: This retrospective study was carried out on the records of 84 subjects who were treated using CAT. Twenty-eight patients were treated using CAT with a daily use of LIPUS for 20 minutes, 28 patients were treated using CAT with a daily use of PBM for 10 minutes, and 28 patients were treated using CAT alone. The total duration of treatment was recorded for all patients. One-way analysis of variance and post hoc Tukey test were used to assess whether there was any significant difference in total treatment duration among the three groups (P < .05). RESULTS: The mean treatment durations in days were 719 ± 220, 533 ± 242, and 528 ± 323 for the control, LIPUS, and PBM groups, respectively. The LIPUS group showed a 26% reduction, on average, in treatment duration when compared with the control group, whereas the PBM group showed an average 26.6% reduction in the treatment duration when compared with the control group. The results showed that there were statistically significant differences among the groups (P = .011). Treatment durations were significantly reduced in the LIPUS and PBM groups as compared with the control (P = .027 and P = .023, respectively), with no statistically significant differences between the LIPUS and PBM groups (P = .998). CONCLUSIONS: Daily use of LIPUS or PBM as adjunctive interventions during CAT could reduce the duration of orthodontic treatment.


Assuntos
Terapia com Luz de Baixa Intensidade , Aparelhos Ortodônticos Removíveis , Terapia por Ultrassom , Duração da Terapia , Humanos , Estudos Retrospectivos , Ondas Ultrassônicas
7.
BMC Musculoskelet Disord ; 22(1): 725, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34425817

RESUMO

BACKGROUND: Intramedullary screw fixation is considered the standard treatment for proximal fifth metatarsal stress fractures. Low-intensity pulsed ultrasound (LIPUS) is a well-known bone-healing enhancement device. However, to the best of our knowledge, no clinical study has focused on the effect of LIPUS for postoperative bone union in proximal fifth metatarsal stress fractures. This study aimed to investigate the effect of LIPUS treatment after intramedullary screw fixation for proximal fifth metatarsal stress fractures. METHODS: Between January 2015 and March 2020, patients who underwent intramedullary screw fixation for proximal fifth metatarsal stress fractures were investigated retrospectively. All patients underwent intramedullary screw fixation using a headless compression screw with autologous bone grafts from the base of the fifth metatarsal. The time to restart running and return to sports, as well as that for radiographic bone union, were compared between groups with or without LIPUS treatment. LIPUS treatment was initiated within 3 weeks of surgery in all cases. RESULTS: Of the 101 ft analyzed, 57 ft were assigned to the LIPUS treatment group, and 44 ft were assigned to the non-LIPUS treatment group. The mean time to restart running and return to sports was 6.8 and 13.7 weeks in the LIPUS treatment group and was 6.2 and 13.2 weeks in the non-LIPUS treatment group, respectively. There were no significant differences in these parameters between groups. In addition, the mean time to radiographic bone union was not significantly different between the LIPUS treatment group (11.9 weeks) and the non-LIPUS treatment group (12.0 weeks). The rate of postoperative nonunion in the LIPUS treatment group was 0% (0/57), while that in the non-LIPUS treatment group was 4.5% (2/44). However, this difference was not statistically significant. CONCLUSIONS: There were no statistically significant differences regarding the time to start running, return to sports, and radiographic bone union in patients with or without LIPUS treatment after intramedullary screw fixation for proximal fifth metatarsal stress fractures. Therefore, we cannot recommend the routine use of LIPUS to shorten the time to bone union after intramedullary screw fixation for proximal fifth metatarsal stress fractures.


Assuntos
Fraturas de Estresse , Ossos do Metatarso , Parafusos Ósseos , Fixação Interna de Fraturas , Fraturas de Estresse/diagnóstico por imagem , Fraturas de Estresse/cirurgia , Humanos , Ossos do Metatarso/diagnóstico por imagem , Ossos do Metatarso/cirurgia , Estudos Retrospectivos , Ondas Ultrassônicas
8.
Ultrason Sonochem ; 77: 105693, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34343823

RESUMO

This paper presents a means to modify the attributes of okara fiber using ultrasonic and high-speed shearing treatment. The results of scanning electron microscopy and differential scanning calorimetry reveal that the modified okara fiber demonstrates small particle size and high thermal stability. When the 500 W-15,000 rpm combination is used for okara-fiber treatment, the latter exhibits excellent swelling (SC) as well as water- and oil-holding capacities. When 6% of modified okara fiber is added to the dough, the resulting cookies demonstrate the best printing performance. Subsequently, the printing parameters can be optimized to obtain the best filling rate of 30%. The corresponding nozzle diameter and printing speed equal 0.8 mm and 50 mm/s, respectively. Finally, the 3D-printed cookies containing okara fiber are compared against those commonly available in the market via sensory evaluation. As observed, the 3D-printed cookies were more acceptable to people. Therefore, the addition of the okara dietary fiber to the cookie dough not only improves the okara utilization rate but also increases the dietary-fiber content in the cookie, thereby alleviating the occurrence of obesity in modern society.


Assuntos
Fenômenos Químicos , Fibras na Dieta/análise , Impressão Tridimensional , Ondas Ultrassônicas , Farinha/análise , Manipulação de Alimentos
9.
Ultrason Sonochem ; 77: 105696, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34358883

RESUMO

A novel, green and eco-friendly, cost-effective, fast, and reliable high energy ultrasonication (US) extraction with UHPLC-MSMS (Ultrahigh performance liquid chromatography with mass spectrometry) quantification of Glycyrrhizic acid (GZA) is reported herein for the first time. The study provides useful insights regarding the effect of US-factors with statistical analysis and mechanisms, involved in GZA-extraction and analysis. An US-extraction method (US-MD) was developed using three levels of US factors: solvents (AC (acetone), EtOH (ethanol), H2O (water)), time (1, 2, 3 min), amplitudes (30, 40, 50%), pulse (10/0.5, 20/0.5, 30/0.5 sec), particle sizes (0.5, 1, 1.4 mm), and temperatures (20, 30, 40 °C). The US-MD was further validated with high accuracy 98.96 ± 6.82 and r2 = 0.995 whereas, an in-house analytical method (UHPLC-MSMS) was developed and validated to quantify the GZAamount. UHPLCMSMS-MD resulted in a retention time of 0.31 min with MSMS (821.400 > 351.200) in a 1 min run time whereas, UHPLCMSMS-MV showed high accuracy and precision with r2 = 0.998 for GZA. Statistical analysis of K-mean clustering finalized US-set-of-factors showing optimum extract yield (mg/1mg) of 0.48 with sum (2.41 ± 014) and mean (0.27) along with a high GZA-amount (µg/mg) of 8.23 with sum (43.31 ± 2.07) and mean (4.81) for H2O in 3 min at 40 °C using particle size (1.4 mm), amplitude (50%), and pulse (30/0.5). Large scale application of US-UHPLCMSMS confirmed the evaluation power of the method showing the order for GZA amount; Egypt > Pakistan > Syria > India > Palestine > America > Georgia > Morocco. A significant effect for US factors Vs extract yield and GZA amount was observed however, solvent*GZA-amount and extract yield*particle size were more significantly correlated compared to time*temperature*amplitude*pulse analyzed via PCA, GLM-UniANOVA, K-mean, and Pearson's correlation (P ≤ 0.05). A combined mechanism of shear stress, macroturbulence due to acoustic cavitation and implosions, sonochemical, and sonocapillary effect were noted for the US technique producing higher extract yield and GZA amount from licorice.


Assuntos
Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão , Glycyrrhiza/química , Ácido Glicirrízico/análise , Ácido Glicirrízico/isolamento & purificação , Espectrometria de Massas em Tandem , Ondas Ultrassônicas , Química Verde , Fatores de Tempo
10.
Nat Commun ; 12(1): 5001, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408151

RESUMO

As a basic structure of most polypyridinal metal complexes, [Ru(bpy)3]2+, has the advantages of simple structure, facile synthesis and high yield, which has great potential for scientific research and application. However, sonodynamic therapy (SDT) performance of [Ru(bpy)3]2+ has not been investigated so far. SDT can overcome the tissue-penetration and phototoxicity problems compared to photodynamic therapy. Here, we report that [Ru(bpy)3]2+ is a highly potent sonosensitizer and sonocatalyst for sonotherapy in vitro and in vivo. [Ru(bpy)3]2+ can produce singlet oxygen (1O2) and sono-oxidize endogenous 1,4-dihydronicotinamide adenine dinucleotide (NADH) under ultrasound (US) stimulation in cancer cells. Furthermore, [Ru(bpy)3]2+ enables effective destruction of mice tumors, and the therapeutic effect can reach deep tissues over 10 cm under US irradiation. This work paves a way for polypyridinal metal complexes to be applied to the noninvasive precise sonotherapy of cancer.


Assuntos
Antineoplásicos/química , Neoplasias/terapia , Rutênio/química , Terapia por Ultrassom , Animais , Antineoplásicos/administração & dosagem , Humanos , Camundongos , Camundongos Endogâmicos BALB C , NAD/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Oxirredução/efeitos da radiação , Porfirinas/química , Rutênio/administração & dosagem , Oxigênio Singlete/metabolismo , Ondas Ultrassônicas
11.
Molecules ; 26(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34361588

RESUMO

Psophocarpus tetragonolobus has long been used in traditional medicine and cuisine. In this study, Psophocarpus tetragonolobus extracts were isolated by maceration and ultrasound-assisted extraction and were evaluated for their antioxidant and anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. The obtained results show that both extracts (maceration and ultrasound) were rich in bioactive molecules and exerted substantial antioxidant and anti-inflammatory effects. The P. tetragonolobus extracts' treatment in LPS-stimulated RAW264.7 macrophages resulted in a significant downregulation of the expressions of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1ß mRNA. In addition, the P. tetragonolobus extracts' treatment attenuated inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression. Our observations indicate that there is no significant difference between the two studied extracts of P. tetragonolobus in terms of biological properties (specifically, antioxidant and anti-inflammatory effects. Regardless of the extraction method, P. tetragonolobus could be used for treating diseases related to oxidative stress and inflammatory reactions.


Assuntos
Anti-Inflamatórios , Antioxidantes , Fabaceae/química , Macrófagos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Citocinas/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células RAW 264.7 , Ondas Ultrassônicas
12.
J Acoust Soc Am ; 150(1): 241, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34340483

RESUMO

Double-strand breaks (DSBs) of giant DNA molecules after exposure to 1.0 MHz pulsed-wave ultrasound were quantitatively evaluated by single-molecule observation of giant DNA (T4 GT7 DNA; 166 kbp) through fluorescence microscopy. Aqueous solutions of DNA were exposed to ultrasonic waves with different sound pressures, repetition periods (1, 2, 5 ms), and pulse durations (5, 10, 50 µs). Below a threshold value of sound pressure, almost no double-strand breaks were generated, and above the threshold, the degree of damage increased in an accelerated manner as the pressure increased. DNA damage was much more severe for exposure to ultrasound with a shorter pulse duration. In addition, a longer pulse repetition period caused worse damage in DNA molecules. The effect of microbubbles on the damage induced by exposure to ultrasound had also been studied. While a result showed that a very small amount of microbubbles increased DSBs of DNA, this effect of microbubbles only weakly depended on their concentrations.


Assuntos
DNA , Ondas Ultrassônicas , Microbolhas , Ultrassonografia
13.
Chem Commun (Camb) ; 57(60): 7438-7440, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34232244

RESUMO

Mechanical force applied by ultrasound in solution leads to the dissociation of DNA metallo-base-pair interactions when these motifs are functionalized with oligodeoxynucleotide sequences of sufficient length. The annealing and force-induced denaturing process is followed by the attachment of distance-sensitive fluorescent probes and is found to be reversible.


Assuntos
DNA/química , Oligodesoxirribonucleotídeos/química , Prata/química , Pareamento de Bases , DNA/genética , DNA/efeitos da radiação , Fluoresceínas/química , Corantes Fluorescentes/química , Hibridização de Ácido Nucleico/efeitos da radiação , Oligodesoxirribonucleotídeos/genética , Oligodesoxirribonucleotídeos/efeitos da radiação , Ondas Ultrassônicas
14.
Ultrason Sonochem ; 76: 105653, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34198127

RESUMO

The review focus on the effect of ultrasound on protein functionality. The presence of transient ultrasonic mechanical waves induce various sonochemical and sonomechanical effects on a protein. Sonochemical effects include the breakage of chains and/or the modification of side groups of aminoacids. Sonomechanical modifications by enhanced molecular agitation, might lead to the transient or permanent modification of the 3D structure of the folded protein. Since the biological function of proteins depends on the maintenance of its 3D folded structure, both sonochemical and sonomechanical effects might affect its properties. A protein might maintain its 3D structure and functionality after minor sonochemical effects, however, the enhanced mass transfer by sonomechanical effects might expose internal hydrophobic residues of the protein, making protein unfolding to an irreversible denatured state. Ultrasound enhanced mass transport effects are unique pathways to change the 3D folded structure of proteins which lead to a new functionality of proteins as support shield materials during the formation microspheres. Enzymes are proteins and their reactions should be conducted in a reactor set-up where enzymes are protected from sonic waves to maximize their catalytic efficiency. In this review, focused examples on protein dispersions/emulsions and enzyme catalysis are given.


Assuntos
Proteínas/metabolismo , Ondas Ultrassônicas , Dobramento de Proteína , Proteínas/química
15.
Ultrason Sonochem ; 76: 105654, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34198128

RESUMO

Antioxidant products present a very high added value and are demanded in the market. The optimization of their extraction is a high-stakes matter for both economic and environmental points of view. Ultrasound extraction has been considered one of the most promising methods, so the relative importance of key parameters may have decisive economic significance. For this reason, different parameters that have influence on the extraction capacity such as ultrasound power, time, temperature, pH and % ethanol in water have been studied to know the relationships between the independent parameters and their influence on the extraction from Eucalyptus globulus leaves. An experimental Box-Behnken factorial design and subsequent analysis by neural networks have been used. The relative influence of each parameter varies according to the nature of the extracted compound. In this regard, the higher capacity of extraction of the selected antioxidant compounds by means of the variation of the operation conditions can be facilitated. For all the studied compounds, temperature has been the most important parameter for their extraction. The relative content (%) of bioactive compounds (terpenes) in the optimized Eucalyptus globulus extract has been performed by GC-MS analysis.


Assuntos
Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Eucalyptus/química , Folhas de Planta/química , Ondas Ultrassônicas , Antioxidantes/química , Concentração de Íons de Hidrogênio , Temperatura , Fatores de Tempo
16.
Ultrason Sonochem ; 76: 105655, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34225214

RESUMO

Resistant starch type 2 (RS) was isolated from lotus stem using enzymatic digestion method. The isolated RS was subjected to ultrasonication (US) at different sonication power (100-400 W). The US treated and untreated RS samples were characterized using dynamic light scattering (DLS), scanning electron microscopy (SEM), light microscopy and Fourier transform infrared spectroscopy (FT-IR). DLS revealed that particle size of RS decreased from 12.80 µm to 413.19 nm and zeta potential increased from -12.34 mV to -26.09 mV with the increase in sonication power. SEM revealed smaller, disintegrated and irregular shaped RS particles after ultrasonication. FT-IR showed the decreased the band intensity at 995 cm-1 and 1047 cm-1 signifying that US treatment decreased the crystallinity of RS and increased its amorphous character. The bile acid binding, anti-oxidant and pancreatic lipase inhibition activity of samples also increased significantly (p < 0.05) with the increase in sonication power. Increase in US power however increased the values of hydrolysis from 23.11 ± 1.09 to 36.06 ± 0.13% and gylcemic index from 52.39 ± 0.38 to 59.50 ± 0.11. Overall, the non-thermal process of ultrasonic treatment can be used to change the structural, morphological and nutraceutical profile of lotus stem resistant starch which can have great food and pharamaceutical applications.


Assuntos
Lotus/química , Caules de Planta/química , Amido Resistente/análise , Ondas Ultrassônicas , Absorção Fisico-Química , Valor Nutritivo
17.
Ultrason Sonochem ; 76: 105657, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34229120

RESUMO

This research evaluated the effects of multi-frequency ultrasound assisted freezing (UAF) on the freezing rate, structural characteristics, and quality properties of cultured large yellow croaker. The freezing effects with triple ultrasound-assisted freezing (TUF) at 20, 28 and 40 kHz under 175 W was more obvious than that of single ultrasound-assisted freezing (SUF) at 20 kHz and dual ultrasound-assisted freezing (DUF) at 20 and 28 kHz. The results showed that UAF significantly increased the freezing rate and better preserved the quality of frozen large yellow croaker samples. Specifically, the quality parameters of the TUF-treated samples were closer to those of the fresh samples, with greater texture characteristics, a larger water holding capacity (lower thawing loss and cooking loss), lower K values and lower thiobarbituric acid reactive substances values. Light microscopy observation images revealed that the ice crystals formed by TUF were fine and evenly distributed, resulting in less damage to the frozen large yellow croaker samples. Therefore, multi-frequency UAF could improve the quality properties of the large yellow croaker samples.


Assuntos
Qualidade dos Alimentos , Congelamento , Perciformes , Ondas Ultrassônicas , Animais
18.
Ultrason Sonochem ; 76: 105658, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34242865

RESUMO

Phenolic compounds are secondary metabolites involved in plant adaptation processes. The development of extraction procedures, quantification, and identification of this compounds in habanero pepper (Capsicum chinense) leaves can provide information about their accumulation and possible biological function. The main objective of this work was to study the effect of the UAE method and the polarity of different extraction solvents on the recovery of phenolic compounds from C. chinense leaves. Quantification of the total phenolic content (TPC), antioxidant activity (AA) by ABTS+ and DPPH radical inhibition methods, and the relation between the dielectric constant (ε) as polarity parameter of the solvents and TPC using Weibull and Gaussian distribution models was analyzed. The major phenolic compounds in C. chinense leaves extracts were identified and quantified by UPLC-PDA-ESI-MS/MS. The highest recovery of TPC (24.39 ± 2.41 mg GAE g-1 dry wt) was obtained using MeOH (50%) by UAE method. Correlations between TPC and AA of 0.89 and 0.91 were found for both radical inhibition methods (ABTS+ and DPPH). The Weibull and Gaussian models showed high regression values (0.93 to 0.95) suggesting that the highest phenolic compounds recovery is obtained using solvents with "ε" values between 35 and 52 by UAE. The major compounds were identified as N-caffeoyl putrescine, apigenin, luteolin and diosmetin derivatives. The models presented are proposed as a useful tool to predict the appropriate solvent composition for the extraction of phenolic compounds from C. chinense leaves by UAE based on the "ε" of the solvents for future metabolomic studies.


Assuntos
Antioxidantes/isolamento & purificação , Capsicum/química , Fracionamento Químico/métodos , Fenóis/isolamento & purificação , Folhas de Planta/química , Solventes/química , Ondas Ultrassônicas , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Fenóis/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
19.
Ultrason Sonochem ; 76: 105659, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34242867

RESUMO

This study evaluated the effects of high intensity ultrasonication (HIU, 100, 150, 200, and 250 W) and treatment time (0, 3, 6, 9, and 12 min) on the structure and emulsification properties of myofibrillar proteins (MPs) from Coregonus peled. These investigations were conducted using an ultrasonic generator at a frequency of 20 kHz (ultrasonic probe). Analysis of the carbonyl content and total number of sulfhydryl groups showed that HIU significantly improved the oxidative modification of MPs (P < 0.05). SDS-PAGE profiling showed significant degradation of the myosin heavy chain (P < 0.05). In addition, Fourier transformed infrared spectroscopy (FTIR) revealed that HIU altered these treated MP secondary structures, this was due to molecular unfolding and stretching, exposing interior hydrophobic groups. Particle size analysis showed that HIU treatment reduced particle sizes. Solubility, emulsification capacity, and emulsion stability were improved significantly, and each decreased with an increase in treatment time (up to 12 min), indicating aggregation with prolonged sonication. These results indicate that HIU could improve the emulsification properties of MPs from C. peled, demonstrating a promising method for fish protein processing.


Assuntos
Proteínas de Peixes/química , Proteínas Musculares/química , Salmonidae , Ondas Ultrassônicas , Animais , Emulsões , Interações Hidrofóbicas e Hidrofílicas
20.
Ultrason Sonochem ; 76: 105661, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34252684

RESUMO

In this work, extraction of flavonoids from peanut shells has been studied in the presence of ultrasound and the results are compared with Soxhlet and heat reflux extraction for establishing the process intensification benefits. The process optimization for understanding the effects of operating parameters, such as ethanol concentration, particle size, solvent to solid ratio, extraction temperature, ultrasonic power and ultrasonic frequency, on the extraction of flavonoids has been investigated in details. The highest extraction yield (9.263 mg/g) of flavonoids was achieved in 80 min at optimum operating parameters of particle size of 0.285 mm, solvent to solid ratio of 40 ml/g, extraction temperature of 55 °C, ultrasonic power of 120 W and ultrasonic frequency of 45 kHz with 70% ethanol as the solvent. Two kinetic models (i.e. phenomenological model and Peleg's model) have been introduced to describe the extraction kinetic of flavonoids by fitting experimental data and predict kinetic parameters. Good performance with slight loss of goodness of fit of two models was found by comparing their coefficient of determination (R2), root mean square error (RMSE) and/or mean percentage error (MPE) values. This work would provide the reduction of degradation and the economic evaluation for the extraction processes of flavonoids from peanut shells, as well as give a better explanation for the mechanism of ultrasound.


Assuntos
Arachis/química , Fracionamento Químico/métodos , Flavonoides/isolamento & purificação , Ondas Ultrassônicas , Cinética
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