Ultrasonics Sonochemistry最新文献

In the present study, a statistical tool called the simplex lattice mixture design method was used to create a new formulation of Natural Deep Eutectic Solvent (NADES), which is derived from a combination of three compounds (citric acid, glycerol, and water) to extract bioactive compounds from chickpea (Cicer arietinum L.) sprouts. The mixture (natural deep eutectic solvent) was formulated by combining three solvents including citric acid, glycerol, and water. The extraction was performed in a sonication bath for 30 min. The simultaneous optimization was performed to obtain the highest total polyphenol content (TPC), total flavonoid content (TFC) and antioxidants activity. The highest values of total polyphenol content (TPC), total flavonoid content (TFC) and antioxidant activity were 128.0 ± 0.2 mg GAE/100 g, 38.61 ± 0.03 mg CE/100 g and 2117 ± 1.8 µmol TE/100 g respectively. HPLC-DAD of the optimized extract was utilized for quantification of polyphenol compounds showing catechin as the main compound followed by chlorogenic acid, epicatechin, syringic acid, rutin, gallic acid, kaempferol 3-glucoside, ferulic acid, and coumaric acid. These findings may represent a significant advancement in the management of phenolic compound extraction for targeted uses, such as serving as alternatives to traditional antioxidants primarily employed in the food industry to improve nutritional quality. Furthermore, our research has shown that mixture designs are an efficient and useful method for structuring and optimizing experimental parameters to achieve the most accurate results with the minimum number of experiments.

This work assessed the efficiency and sustainability of ultrasound-assisted extraction (UAE) of anthocyanins from grape pomace using bio-based solvents: Ethanol, Isopropanol, Propylene-glycol, and Ethylene-glycol at different concentrations (50 and 100 % v/v) and temperatures (25 °C and 50 °C). Higher ultrasonic intensities (UI) were obtained at 50 °C and 50 % v/v by decreasing solvents viscosities. Under these conditions, anthocyanin extractions were performed with different combinations of solvent to liquid ratio (SLR) at 1:10 and 1:50 g/mL, and UI (3.9 and 13.9 W/cm²). Samples were taken from 0 to 40 min. Ultrasound induced a fast extraction of anthocyanins: a plateau was reached at 5 min and the continuation of the sonication only provoked a marginal increase which is transferred in lower Productivity (Pr) rand higher energy consumptions. The COSMO-SAC model validated solute-solvent interactions, providing robust predictive insights where ethanol showed the highest anthocyanin extraction and productivities (1.094 kg/hL). However, propylene-glycol showed the highest eco-scale scores (∼ 80) within the range defined as "Excellent" and antioxidant capacity (2758.34 ± 6.26 μmol TE/g DM) regardless of the UI, and with very low energy consumption when the extraction was performed at 3.9 W/cm² and SLR of 1:10 g/mL. These results show that integration of UAE and bio-based solvents presented a sustainable and efficient method for valorizing wine making by-products, with significant improvements with respect to the conventional extraction, thus promoting eco-friendly practices for the food industry, and supporting the circular economy.

Three-phase partitioning (TPP) is promising for isolating bioactive polysaccharides, but t-butanol's environmental impact limits its application. Deep eutectic solvents can serve as a green and recyclable alternative to t-butanol. This study introduces an ultrasonic-assisted DES three-phase partitioning (UA-TPP-DES) system to extract and purify American ginseng polysaccharides (AGPs). The optimized DES-4, composed of lauric acid and nonanoic acid (molar ratio = 1:1), achieved a 35.28 % extraction yield under specific conditions and can be recycled five times with minimal yield loss. AGP-DES-4 has a broad molecular weight distribution (2.48-174.64 kDa) and mainly consists of mannose, glucose, galactose, and arabinose. In vivo Drosophila models show that AGP-DES-4 improves UC fly survival and enhances intestinal barrier function by regulating the proliferation and differentiation of intestinal epithelial cells (IECs) and intestinal stem cells (ISCs). Our results highlight the effectiveness of the AGP-DES-4 extraction method and its potential therapeutic value for treating UC.

In this study, the electrochemical and anodic behaviors of Pb-Ag anodes during ultrasound-assisted zinc electrowinning were meticulously examined. The oxygen evolution reaction (OER) occurring at the Pb-Ag anodes in a 150 g L^-1 aqueous H₂SO₄ solution was studied in the absence (silent) and presence of ultrasonication (40 kHz, 100 % acoustic amplitude). Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), linear sweep voltammetry (LSV), and zinc electrowinning tests were conducted to analyze the electrochemical behavior of the Pb-Ag anodes during zinc electrowinning. Compared with that under silent conditions, the OER was greatly enhanced under ultrasonic conditions, and the overpotential reduction was found to be 108 mV at 35 °C at a current density of 50 mA cm^-2. A significant reduction in the bath voltage was achieved during ultrasound-assisted prolonged zinc electrowinning, with a difference of approximately 50 mV compared with that of the control. The integration of ultrasonic technology into the realm of zinc electrowinning leverages the physical and chemical effects of ultrasonication to significantly improve the efficiency and kinetics of the OER. Smaller PbO₂ grains and a larger silver exposure area appeared on the Pb-Ag plate surface during ultrasonic-assisted electrowinning, which is beneficial for the OER chemically. The generated oxygen bubbles merged more rapidly and detached from the electrode surface with greater alacrity under ultrasonication conditions, which reinforced the OER in terms of mass transfer kinetics. Furthermore, more fine zinc products can be obtained during ultrasound-assisted zinc electrowinning. By harnessing the power of ultrasonic technology, more sustainable and cost-effective zinc electrowinning can be achieved.

Escalating global protein demand necessitates the commercialization of protein rich products. Oat is a promising high-quality protein source but it requires structural and functional modifications to diversify its application. The current investigation was focused on the impact of different powers of ultrasonic waves (200, 400, and 600 W) on structural and functional characteristics of oat protein isolates to improve its techno-functional properties. Higher strength ultrasound waves generated flat sheet structures which were observed while analyzing microstructure of oat protein isolate (OPI). However, non-significant variation in molecular weight distribution were observed in different treatments. At 600 W power of ultrasonic waves the protein fragments show local accumulation, increased α-helix content. Due to uncoiling of protein structure decrease in β-sheets and β-turns was also observed at 600 W. Protein turbidity decreased significantly under low power ultrasonic treatment (200 W) which significantly increased at higher power. Moderate ultrasonic treatment (400 W) promoted protein dissolution, and maintained a good balance between β-sheets (71.04 ± 0.08), α-helix (16.27 ± 0.02) and β-turns (12.68 ± 0.03), exhibiting optimized flexibility and structural integrity. Whereas, higher strength (600 W) significantly destroyed protein structure. The amino acid content decreased significantly with increasing ultrasonic power. The thermal characteristics of OPI remained unaffected after ultrasound treatment. In conclusion, modifications of secondary and tertiary structure induced by moderate ultrasonic treatment (400 W) improved functional properties of OPI. The 400 W treatment resulted in highest essential amino acid content (EAA) i.e., 22.75 ± 0.82 mg/100 mg and total amino acid content (TAA) i.e., 64.94 ± 2.7 mg/100 mg, which are significantly higher than WHO and FAO standards, suggesting best total and essential amino acid production in comparison to other treatments.

This research aimed to investigate and compare the effect of bath and horn ultrasound-assisted bleaching of sunflower oilon the degradation of tocopherols and sterols, production of volatile substances, and oxidation indices, including thiobarbituric acid (TBA) and peroxide value (PV) and with that of the industrial bleaching process. Ultrasonic bath and ultrasonic horn bleaching techniques reduced sunflower oil's total tocopherol and total sterol contents to a greater extent than conventional bleaching techniques. While bath and horn sonication operated theoretically equivalent power settings, power meter measurements demonstrated that the bath sonicator delivered significantly less power than the horn sonicator. Among the ultrasonic bleaching techniques, the ultrasonic bath at 400 W showed the lowest reduction in total tocopherols,sterols and volatile compounds compared to the ultrasonic horn technique at the same theoritical power. Moreover, Despite the 800 W bath sonicator having significantly higher nominal power than the 400 W horn sonicator, the horn sonicator was considerably more effective at degrading bioactive compounds. Higher degradation of bioactive compounds coincided with increasing patterns in primary and secondary oxidation indices and volatile compounds in horn compared to bath and industrial bleaching due to the direct effect of ultrasonic horn and free radical formations.

Ultrasonic reactors, widely applied in process intensification, face limitations in their industrial application due to a lack of theoretical support for their structural design and optimization, particularly concerning the uniformity of the cavitation zone. Addressing this gap, our study introduces a novel approach to design a multi-frequency octagonal ultrasonic reactor of capacity 9.5 L through numerical simulation and spectrum analysis. The effects of reactor shape, transducer position, and multi-frequency ultrasound interaction on the sound pressure distribution in the reactor were simulated, employing a linear wave equation that accounts for the inhomogeneous distribution of bubbles. The accuracy of sound pressure amplitude predictions has been validated through a multi-frequency simulation method, exhibiting good consistency with experimental data. The results revealed that an octagonal structure with transducers positioned at the bottom and sides enhances the uniformity and distribution of the cavitation area compared to traditional rectangular designs. Notably, the combination of 20 and 40 kHz frequencies at a driving pressure of 3 bar significantly enhances cavitation rates to 69.2 %, surpassing the single frequency of 40 kHz by an increase of 16.5 %. The enhanced cavitation rate can be attributed to the dual-frequency operation, which facilitates larger bubble radii, along with higher collapse temperatures and pressures, as determined through bubble dynamics calculations. Moreover, spectrum analysis method enables energy separation, showing that the introduction of a 40 kHz transducer into a 20 kHz field markedly strengthens both steady and transient cavitation intensities. These findings offer practical insights for their structural design and optimization, paving the way for their broader industrial application.

This work aimed to investigate the effects of ultrasound assisted enzymatic deamidation by protein-glutaminase (PG) on the dispersion of myofibrillar protein (MP) in low-salt solutions. The solubility, structural characteristics, transmission electron microscopy, asymmetric-flow field-flow fractionation, steady shear rheological property and multiple light scattering of MP deamidated by PG (MP-PG) and MP pretreated with ultrasound followed by PG deamidation (MP-U-PG) were determined. Molecular docking and molecular dynamics (MD) simulations were used to estimate the interaction between PG and MP. Under ultrasound assistance, the MP deamidated for 16 h (MP-U-PG16) showed the highest solubility (80.1 %) in low-salt conditions, which is attributed to its highest absolute zeta potential and smallest particle size. Although secondary structure analysis showed that MP-PG and MP-U-PG had an increased α-helix ratio and a decreased β-sheet ratio, ultrasonic treatment had a significantly influence on the MD results. The results manifested that hydrogen bond was the primary forces driving the binding between PG and MP, and the hydrogen bond and hydrophobic interaction were the dominant forces responsible the binding between PG and MP pretreated with ultrasound. According to the energy landscapes theory, ultrasound could overcome the energy barriers through external force input and find the best pathway to achieve the final lowest energy state. Our research contributed to the improvement of the colloidal dispersibility of MPs under low-salt conditions and the regulation of protein interaction by ultrasound assistance.

The study aimed to investigate the effect of thermosonication (TS; 37 KHz, 300 W; 30, 40, 50, and 60 °C for 10 min) and NaCl (12 % w/v) on the inactivation of Staphylococcus aureus and Shigella flexneri in lettuce, as well as to examine the kinetics of inactivation and the thermodynamic behaviors of the process. Computational Fluid Dynamics (CFD) simulations were employed to analyze the acoustic pressure field, velocity contours, and streamlines. The results showed that NaCl addition had the least impact on inactivation compared to TS and combined NaCl + TS. Increasing the temperature led to higher inactivation of both bacteria, with a more significant effect at 60 °C. Thermosonication treatment had a more consistent effect on inactivation compared to the addition of NaCl. When exposed to thermosonication, the population of S. aureus and S. flexneri could be reduced by 5.1 to 6.9 log CFU/g and 5.5 to 7.4 log CFU/g, respectively, at temperature levels of 30 and 60 °C. Additionally, no significant relationship between entropy reduction and type of microorganisms was observed. The samples that were treated only with NaCl had higher energy absorption than the other samples.

Ischemia brain injury is closely associated with the gut microbiota. Polysaccharides, as a typical prebiotic, have been extensively employed in stroke treatment. In our previous study, Pueraria lobata polysaccharide (PLP-3) with antioxidant activity was prepared via water extraction and alcohol precipitation combined with ultrasonic degradation. In this study, the effects of PLP-3 on ischemia brain injury and its regulatory effects on the gut microbiota were further investigated. The results demonstrated that PLP-3 effectively reduced the infarct area, improves neurological function, and alleviates neuronal damage of cerebral ischemia injury. Mechanistically, PLP-3 significantly reduces serum LPS levels in MCAO mice, inhibiting TLR-4 activation in brain tissue and thereby reducing IL-1β and TNF-α levels. Meanwhile, PLP-3 significantly repaired the intestinal barrier injury by increasing the expression of tight junction proteins (ZO-1 and Occludin) and increasing the number of goblet cells. Additionally, the structure and composition of gut microbiota in MCAO mice after PLP-3 intervention, were also significantly changed, especially the enrichment of Lactobacillus and the reduction of Corynebacterium and Staphylococcus. At the same time, short chain fatty acid, metabolites of gut microbiota, were also significantly increased and significantly correlated with the abundance of Lactobacillus. Moreover, LC-MS untargeted metabolomics revealed that PLP-3 significantly improves the intestinal metabolic profile after cerebral ischemia injury, upregulating the amino acid biosynthesis pathway and enriching amino acids such as glutamine and arginine, as well as neuroprotective flavonoids such as fisetin and liquiritigenin. These results suggested that PLP-3 could protect mice from cerebral ischemia-reperfusion injury by regulating gut microbiota and repairing gut barrier, inhibiting brain LPS/TLR4/MyD88 inflammatory pathway, therefore we provide a theoretical basis for PLP-3 as a functional food to prevent ischemic brain injury.