Optimizing extraction methods by a comprehensive experimental approach and characterizing polyphenol compositions of Ecklonia radiata.

Brown seaweed Ecklonia radiata harbors valuable polyphenols, notably phlorotannins, prized for their health benefits. This study optimized phlorotannin extraction via conventional solvent extraction and ultrasound-assisted extraction methods, utilizing variable concentrations of ethanol. Employing fractional factorial designs, key variables were identified. Steepest ascent/descent method and central composite rotatable designs refined optimal conditions, enhancing phlorotannin and polyphenol yields, and antioxidant capacities. Under optimized conditions, phlorotannin contents reached 2.366 ± 0.01 and 2.596 ± 0.04 PGE mg/g, total polyphenol contents peaked at 10.223 ± 0.03 and 10.836 ± 0.02 GAE mg/g. Robust antioxidant activity was observed: DPPH and OH radical scavenging capacities measured 27.891 ± 0.06 and 17.441 ± 0.08 TE mg/g, and 37.498 ± 1.12 and 49.391 ± 0.82 TE mg/g, respectively. Reducing power capacities surged to 9.016 ± 0.02 and 28.110 ± 0.10 TE mg/g. Liquid chromatography-mass spectrometry (LC-MS) and high-performance liquid chromatography (HPLC) analyses revealed enriched antioxidant compounds. Variations in polyphenol profiles were noted, potentially influencing antioxidant capacity nuances. This study illuminated the potential of E. radiata potential as a polyphenol source and offers optimized extraction methods poised to benefit various industries.

Review on the impacts of external pressure on sonochemistry.

The impact of hydrostatic pressure, commonly known as ambient or external pressure, on the phenomenon of sonochemistry and/or sonoluminescence has been extensively investigated through a multitude of experimental and computational studies, all of which have emphasized the crucial role played by this particular parameter. Numerous previous studies have successfully demonstrated the existence of an optimal static pressure for the occurrence of sonoluminescence and multi-bubble or single-bubble sonochemistry. However, despite these findings, a universally accepted value for this critical pressure has not yet been established. In addition, it has been found that the cavitation effect is completely inhibited when the static pressure is either too high or too low. This comprehensive review aims to delve into the primary experimental results and elucidate their significance in relation to hydrostatic pressure. We will then conduct an analysis of numerical calculations, focusing specifically on the influence of external pressure on single bubble sonochemistry. By delving into these calculations, we will be able to gain a deeper understanding of the experimental results and effectively interpret their implications.

Synthesis of ultra-high molecular weight homo- and copolymers via an ultrasonic emulsion process with a fast rate.

In the forefront of advanced materials, ultra-high molecular weight (UHMW) polymers, renowned for their outstanding mechanical properties, have found extensive applications across various domains. However, their production has encountered a significant challenge: the attainment of UHMW polymers with a low dispersity (Ɖ). Herein, we introduce the pioneering technique of ultrasound (US) initiated polymerization, which has garnered attention for its capability to successfully polymerize a multitude of monomers. This study showcases the synthesis of UHMW polymers with a comparatively low Ɖ ( ≤ 1.1) within a remarkably short duration ( ~ 15 min) through the amalgamation of emulsion polymerization and high-frequency ultrasound-initiated polymerization. Particularly noteworthy is the successful copolymerization of diverse monomers, surpassing the molecular weight and further narrowing the Ɖ compared to their respective homopolymers. Notably, this includes monomers like vinyl acetate, traditionally deemed unsuitable for controlled polymerization. The consistent production and uniform dispersion of radicals during ultrasonication have been identified as key factors facilitating the swift fabrication of UHMW polymers with exceptionally low Ɖ.

Metal-Phenolic Network-Coated Nanoparticles as Stabilizers for the Engineering of Pickering Emulsions with Bioactivity.

Pickering emulsions stabilized by functional nanoparticles (NPs) have received considerable attention for improving the physical stability and biological function of NPs. Herein, hydrophobic polyphenols were chosen as phenolic ligands to form metal-phenolic network (MPN) coatings on NPs (e.g., silica, polystyrene) mediated by the sono-Fenton reaction. The MPN coatings modulated the surface wettability and charges of NPs and achieved emulsification behavior for preparing Pickering emulsions with pH responsiveness and oxidation resistance. A series of polyphenols, including resveratrol, rutin, naringin, and curcumin, were used to form MPN coatings on NPs, which served as stabilizers for the engineering of functionalized oil-in-water (O/W) Pickering emulsions. This work provides a new avenue for the use of hydrophobic polyphenols to modulate NP emulsifiers, which broadens the application of polyphenols for constructing Pickering emulsions with antioxidant properties.

Thermal and structural characteristics of date-pits as digested by Trichoderma reesei.

The objective of this study was to develop functional date-pits by mold digestion for the potential use in food products. Whole date-pits (WDP) and defatted date-pits (DDP) were digested by mold Trichoderma reesei at 20 °C. T. reesei consumed date-pits as nutrients for their growth, and DDP showed higher growth of molds as compared to the WDP. The mold digested WDP and DDP samples showed an increased water solubility and hygroscopicity as compared to the samples prepared by autoclaved. This indicated that the mold digestion transformed date-pits to hydrophilic characteristics. Thermal analysis indicated a structural change at -3.2 °C for the untreated WDP and it was followed by a glass transition shift (i.e. onset: 138 °C and a specific heat change: 295 J/kg oC), and an endothermic peak at 196 °C with enthalpy of 68 J/g for the solids melting-decomposition. Similar characteristics were also observed for treated samples with the two glass transitions. The total specific heat changes for WDP, autoclaved-WDP, and digested-WDP were observed as 295, 367, and 328 J/kg oC, respectively. The total specific heat changes for DDP, autoclaved-DDP, and digested-DDP were observed as 778, 1329, and 1877 J/kg oC, respectively. This indicated that mold digestion transformed more amorphous fraction in the DDP. The energy absorption intensities of the Fourier Transform Infrared (FTIR) spectra for the selected functional groups decreased by the mold digestion.

Bubble oscillations at low frequency ultrasound for biological applications.

Bubbles oscillating in the presence of ultrasound is commonly employed in biomedical applications for drug delivery, ultrasound enhanced thrombolysis, and the transport and manipulation of cells. This is possible because bubbles tend to interact with the ultrasound to undergo periodic shape changes known as shape-mode oscillation, concomitant with the generation of liquid agitation or streaming. This phenomenon is examined both experimentally and theoretically on a single bubble at a frequency of (45 ± 1) kHz. Effects of ultrasonic frequency and power on the flowfield were explored. Experiments revealed different trends in the development of liquid streaming velocities at different acoustic forcing conditions (5.53, 6.80 and 7.02 Vpp), with lowest (0.5 mm/s) and highest (1.1 mm/s) values of time-averaged mean streaming velocity occurring at 6.80 Vpp and 7.02 Vpp, respectively. Simulations captured the simultaneous evolution of bubble-shapes that helped create flow vortices in the liquid surrounding the bubble. These vortices collectively responsible in generating signature patterns in the liquid for a dominant shape-mode of the bubble, and could also generate localised shear stresses for practical application. The velocity and pressure profiles in the liquid around the bubble confirmed the connection of the applied and reflected soundwaves in driving this phenomenon.

Application of ultrasound treatment in pork marination: Effects on moisture migration and microstructure.

To better understanding the effects of ultrasonic marination on the porcine tissue, the moisture migration and microstructure were investigated in this study. Additionally, the acoustic field distribution was analysis using COMSOL Multiphysics. The low-filed NMR results demonstrated that ultrasonic curing induced a leftward shift in T21 and a rightward shift in T22, accompanied by a significant reduction in A22, thereby enhancing the water-holding capacity of pork. The SEM and TEM observation showed that the presence of larger interstitial gaps between muscle fibers facilitated the diffusion of NaCl. The simulation analysis revealed that the acoustic field at 26.8 kHz showed minimal standing wave effects and more pronounced cavitation, which was the main reason for the best curing effect at this frequency. The scale-up test showed the NaCl content in pork reached 1% after ultrasound curing, indicating the potential application of ultrasonic marination technology in domestic refrigerators.

Enhanced sunlight-driven catalysis for hydrogen generation and dye remediation using synergistic p-Co3O4/n-TiO2 nanocomposites.

In this study, p-Co3O4/n-TiO2 nanocomposites were synthesized using different ratios of cobalt and titanium precursors through a hydrothermal method. These nanocomposites demonstrated notable potential in photocatalytic applications for hydrogen production and orange-red dye degradation under sunlight. Various techniques, including XRD, Raman spectroscopy, XPS, FESEM, TEM, and BET analysis, were used to comprehensively characterize their structural, morphological, and optical properties. The nanocomposites exhibited both cubic and tetragonal phases of Co3O4 and TiO2, and their combined effect resulted in a narrowed band gap. Additionally, the presence of Co3O4 induced surface plasmon resonance on the TiO2 surface, effectively impeding electron-hole recombination. The nanocomposites displayed an average particle size of ∼20 to 30 nm with substantial visible light absorption. High crystallinity and well-dispersed nanocomposites were confirmed by XRD and Raman, with BET surface areas ranging between 49 and 106 m2 g-1. Notably, the p-Co3O4/n-TiO2 nanocomposite showed superior photocatalytic activity, achieving a maximum hydrogen generation rate of 1120 µmol h-1 g-1 and an 83% degradation efficiency of the orange-red dye within 6 minutes under sunlight. This study emphasizes the enhanced performance of the p-Co3O4/n-TiO2 nanocomposite, indicating its potential in photocatalytic applications, conforming to a pseudo-first-order kinetics model.

Leveraging new opportunities and advances in high-pressure homogenization to design non-dairy foods.

High-pressure homogenization (HPH) and ultrahigh-pressure homogenization (UHPH) are emerging food processing techniques for stabilizing emulsions and food components under the pressure range from 60 to 400 MPa. Apart from this, they also support increasing nutritional profile, food preservation, and functionality enhancement. Even though the food undergoes the shortest processing operation, the treatment leads to modification of physical, chemical, and techno-functional properties, in addition to the formation of micro-sized particles. This study focuses on recent advances in using HPH/UHPH on plant-based milk sources such as soybeans, almonds, hazelnuts, and peanuts. Overall, this systematic review provides an in-depth analysis of the principles of HPH/UHPH, the mechanism of action, and their applications in other nondairy areas such as fruits and vegetables, meat, fish, and marine species. This work also deciphers the role of HPH/UHPH in modifying food components, their functional quality enhancement, and their provision of oxidative resistance to many foods. HPH is not only perceived as a technique for size reduction and homogenization; however, it does various functions like microbial inactivation, improvement of rheologies like texture and consistency, decreasing of lipid oxidation, and making positive modifications to proteins such as changes to the secondary structure and tertiary structure thereby enhancing the emulsifying properties, hydrophobicity of proteins, and other associated functional properties in many nondairy sources at pressures of 100-300 MPa. Thus, HPH is an emerging technique with a high throughput and commercialization value in food industries.

Highly efficient ultrasound-driven Cu-MOF/ZnWO4 heterostructure: An efficient visible-light photocatalyst with robust stability for complete degradation of tetracycline.

Metal-organic frameworks (MOFs) are a significant class of porous, crystalline materials composed of metal ions (clusters) and organic ligands. The potential use of copper MOF (Cu-BTC) for the sonophotocatalytic degradation of Tetracycline (TC) antibiotic was investigated in this study. To enhance its catalytic efficiency, S-scheme heterojunction was created by combining Cu-BTC with Zinc tungstate (ZnWO4), employing an ultrasound-assisted hydrothermal method. The results demonstrated that the Cu-BTC/ZnWO4 heterojunction exhibited complete removal of TC within 60 min under simultaneous irradiation of visible light and ultrasound. Interestingly, the sonophotocatalytic degradation of TC using the Cu-BTC/ZnWO4 heterojunction showed superior efficiency (with a synergy index of ∼0.70) compared to individual sonocatalytic and photocatalytic degradation processes using the same heterojunction. This enhancement in sonophotocatalytic activity can be attributed to the formation of an S-scheme heterojunction between Cu-BTC and ZnWO4. Within this heterojunction, electrons migrated from Cu-BTC to ZnWO4, facilitated by the interface between the two materials. Under visible light irradiation, the built-in electric field, band edge bending, and coulomb interaction synergistically inhibited the recombination of electron-hole pairs. Consequently, the accumulated electrons in Cu-BTC and holes in ZnWO4 actively participated in the redox reactions, generating free radicals that effectively attacked the TC molecules. This study offers valuable perspectives on the application of a newly developed S-scheme heterojunction photocatalyst, demonstrating its effectiveness in efficiently eliminating diverse recalcitrant pollutants via sonophotocatalytic degradation.

Ultrasound-Assisted Encapsulation of Phytochemicals for Food Applications: A Review.

The use of phytochemicals as natural food additives is a topic of interest for both academic and food industry communities. However, many of these substances are sensitive to environmental conditions. For this reason, encapsulation is usually performed prior to incorporation into food products. In this sense, ultrasound-assisted encapsulation is an emerging technique that has been gaining attention in this field, bringing important advantages for the production of functional food products. This review article covered applications published in the last five years (from 2019 to 2023) on the use of ultrasound to encapsulate phytochemicals for further incorporation into food. The ultrasound mechanisms for encapsulation, its parameters, such as reactor configuration, frequency, and power, and the use of ultrasound technology, along with conventional encapsulation techniques, were all discussed. Additionally, the main challenges of existing methods and future possibilities were discussed. In general, ultrasound-assisted encapsulation has been considered a great tool for the production of smaller capsules with a lower polydispersity index. Encapsulated materials also present a higher bioavailability. However, there is still room for further developments regarding process scale-up for industrial applications. Future studies should also focus on incorporating produced capsules in model food products to further assess their stability and sensory properties.

Ultrasonic and homogenization: An overview of the preparation of an edible protein-polysaccharide complex emulsion.

Emulsion systems are extensively utilized in the food industry, including dairy products, such as ice cream and salad dressing, as well as meat products, beverages, sauces, and mayonnaise. Meanwhile, diverse advanced technologies have been developed for emulsion preparation. Compared with other techniques, high-intensity ultrasound (HIUS) and high-pressure homogenization (HPH) are two emerging emulsification methods that are cost-effective, green, and environmentally friendly and have gained significant attention. HIUS-induced acoustic cavitation helps in efficiently disrupting the oil droplets, which effectively produces a stable emulsion. HPH-induced shear stress, turbulence, and cavitation lead to droplet disruption, altering protein structure and functional aspects of food. The key distinctions among emulsification devices are covered in this review, as are the mechanisms of the HIUS and HPH emulsification processes. Furthermore, the preparation of emulsions including natural polymers (e.g., proteins-polysaccharides, and their complexes), has also been discussed in this review. Moreover, the review put forward to the future HIUS and HPH emulsification trends and challenges. HIUS and HPH can prepare much emulsifier-stable food emulsions, (e.g., proteins, polysaccharides, and protein-polysaccharide complexes). Appropriate HIUS and HPH treatment can improve emulsions' rheological and emulsifying properties and reduce the emulsions droplets' size. HIUS and HPH are suitable methods for developing protein-polysaccharide forming stable emulsions. Despite the numerous studies conducted on ultrasonic and homogenization-induced emulsifying properties available in recent literature, this review specifically focuses on summarizing the significant progress made in utilizing biopolymer-based protein-polysaccharide complex particles, which can provide valuable insights for designing new, sustainable, clean-label, and improved eco-friendly colloidal systems for food emulsion. PRACTICAL APPLICATION: Utilizing complex particle-stabilized emulsions is a promising approach towards developing safer, healthier, and more sustainable food products that meet legal requirements and industrial standards. Moreover, the is an increasing need of concentrated emulsions stabilized by biopolymer complex particles, which have been increasingly recognized for their potential health benefits in protecting against lifestyle-related diseases by the scientific community, industries, and consumers.

Ultrasonics and sonochemistry: Editors' perspective.

Ultrasonic waves can induce physical and chemical changes in liquid media via acoustic cavitation. Various applications have benefitted from utilizing these effects, including but not limited to the synthesis of functional materials, emulsification, cleaning, and processing. Several books and review articles in the public domain cover both fundamental and applied aspects of ultrasonics and sonochemistry. The Editors of the Ultrasonics Sonochemistry journal possess diverse expertise in this field, from theoretical and experimental aspects of acoustic cavitation to materials synthesis, environmental remediation, and sonoprocessing. This article provides Editors' perspectives on various aspects of ultrasonics and sonochemistry that may benefit students and early career researchers.

Visible Light-Accelerated Photoiniferter Polymerization in Ionic Liquid.

The effect of ionic liquids on the reversible addition-fragmentation chain transfer (RAFT) polymerization mediated by a visible-light-induced photoiniferter mechanism was investigated. N,N-Dimethyl acrylamide was polymerized by photoiniferter polymerization in 1-ethyl-3-methylimidazolium ethylsulfate [EMIM][EtSO4] ionic liquid. We observed a considerable increase in the polymerization rate constants in ionic liquids (ILs), as well as in the mixed solvent of water and the IL, compared to those observed with water alone as the solvent. To demonstrate the robustness of the process, block copolymers with varying block ratios were synthesized with precise control over their molecular weight and mass dispersity (D). The very high chain-end fidelity provided by the photoiniferter polymerization in IL was described by using MALDI-ToF MS analysis.

Ultrasonic Transformation of Antibiotic Molecules into a Selective Chemotherapeutic Nanodrug.

Ultrasound-based engineering of carrier-free nanodrugs by supramolecular self-assembly has recently emerged as an innovative and environmentally friendly synthetic approach. By applying high-frequency sound waves (490 kHz) in aqueous solutions, the transformation of small chemotherapeutic and antibiotic drug molecules into carrier-free nanodrugs with anticancer and antimicrobial activities was recently achieved. The transformation of the antibiotic drug molecules, i.e., doxycycline, into stable nanodrugs (~130 nm) with selective anticancer activity was achieved without requiring organic solvents, chemical agents, or surfactants. The obtained nanodrug exhibited reactive oxygen species (ROS)-mediated cytotoxicity on human breast cancer (MDA-MB 231 cells) but a negligible antiproliferative effect on healthy fibroblast cells. Imaging by super-resolution microscopy (STORM) provided insights into the intracellular trafficking and endosomal escape of the nanodrugs. Overall, these findings suggest that small antibiotic drugs can be transformed into chemotherapeutic nanodrugs with high selectivity against cancer cells.

In situ studies on free-standing synthesis of nanocatalysts via acoustic levitation coupled with pulsed laser irradiation.

Acoustic levitation is a distinctive and versatile tool for levitating and processing free-standing single droplets and particles. Liquid droplets suspended in an acoustic standing wave provide container-free environments for understanding chemical reactions by avoiding boundary effects and solid surfaces. We attempted to use this strategy for the production of well-dispersed uniform catalytic nanomaterials in an ultraclean confined area without the addition of external reducing agents or surfactants. In this study, we report on the synthesis of gold and silver nanoparticles (NPs) via acoustic levitation coupled with pulsed laser irradiation (PLI). In situ UV-Visible and Raman spectroscopic techniques were performed to monitor the formation and growth of gold and silver NPs. The PLI was used for the photoreduction of targeted metal ions present in the levitated droplets to generate metal NPs. Additionally, the cavitation effect and bubble movement accelerate the nucleation and decrease the size of NPs. The synthesized Au NPs with âˆ¼ 5 nm size showed excellent catalytic behavior towards the conversion of 4-nitrophenol to 4-aminophenol. This study may open a new door for synthesizing various functional nanocatalysts and for achieving new chemical reactions in suspended droplets.

Ultrasound-enhanced interfacial adsorption and inactivation of soy trypsin inhibitors.

In this study, liquid-liquid interfacial protein adsorption was proposed as a means of inactivating soy trypsin inhibitors (TIs, including Kunitz (KTI) and Bowman-Birk inhibitor (BBI)). Hexane-water was first selected as a model system to compare three emulsification methods (hand shaking, rotor-stator and ultrasound mixing). Ultrasound could generate the smallest and least polydisperse emulsion droplets, resulting in highest interfacial adsorption amount of KTI and BBI as well as the highest inactivation percentage of TIs (p < 0.05). Therefore, ultrasound was selected to further explore the effect of the non-aqueous phase on interfacial adsorption and inactivation kinetics of TIs in a food emulsion system containing vegetable oil (VTO). The adsorption amounts of KTI and BBI in the VTO-aqueous emulsion increased by âˆ¼ 25 % compared to the hexane-aqueous emulsion. In addition, the adsorption amounts of KTI and BBI were rapidly increased as a function of sonication time, especially for the hexane-aqueous emulsion system. This result suggests that such inactivation of TIs could be implemented in continuous systems for large-scale processing. Finally, the pathways of interface-induced inactivation of BBI and KTI were investigated based on separate experiments on individual BBI and KTI systems. The results showed that the interface adsorption caused the changes in the secondary and tertiary structure of KTI that led to its activitation. However, BBI was quite stable at the liquid-liquid interface without significant conformational change. Overall, ultrasound-assisted interfacial adsorption can be considered a rapid and highly efficient method to inactivate KTI.

Critical Analysis of Hydrogen Production by Aqueous Methanol Sonolysis.

Recently, several experimental and theoretical studies have demonstrated the feasibility of enhancing the sonochemical production of hydrogen via methanol pyrolysis within acoustic cavitation bubbles (i.e. sonolysis of aqueous methanol solution). This review includes both the experimental and theoretical achievements in the field of hydrogen production by methanol sonolysis. Additionally, the limits of the process's applicability and plausible solutions are highlighted. The impact of different parameters influencing the process performance is discussed. Finally, the effects of methanol concentration on the size distribution of active cavitation bubbles are analyzed.

The effect of bulk viscosity on single bubble dynamics and sonoluminescence.

In our previous paper, we derived a new single bubble model including the effect of bulk viscosity. To confront it to experiments, single bubble dynamics was measured here in 30% (v/v) glycerol-water mixture under different acoustic amplitudes and compared to models including or not the effect of bulk viscosity. The results showed that calculated bubble dynamics were not significantly affected by the bulk viscosity within the experimental conditions used in this study. However, there was a noticeable delay for the first rebound when bulk viscosity was considered. The corresponding sonoluminescence intensities were collected and compared with theoretical predictions. The results did not allow to discriminate between the two models (one includes the effect of bulk viscosity, the other does not), confirming the negligible effect of bulk viscosity in this condition (30% (v/v) glycerol-water mixture). Due to the instability of a single bubble in higher viscosity solutions, we could not implement experiments that can discriminate between the two models.