Zn-ion batteries(ZIBs) are promising candidates for next-generation energy storage systems due to their high stability, low cost and eco-friendliness. While vanadate is widely used as cathode materials in ZIBs, vanadate-based cathodes have been considered impractical for high-rate operation because of their low electrical conductivity, slow Zn ion diffusion kinetics, and the unsustainability of repetitive insertion and extraction at high current densities. In this study, PEDOT:PSS was successfully intercalated into the interlayers of ammonium vanadate nanofibers (EP-AVNF) using the sonochemical method, resulting in high performance for ZIBs with excellent rate capability and stability. Acoustic cavitation occurring under ultrasonic irradiation simultaneously induced oxolation and olation reactions leading to the growth of vanadate nanofibers, as well as in situ oxidative polymerization and interlayer intercalation of PEDOT:PSS, outcomes that were not obtained under silent (stirring-only) conditions. The presence of intercalated PEDOT:PSS not only efficiently expanded the structural interlayer of vanadate but also enhanced its electrical conductivity. Additionally, chemical bonding with vanadate accompanied the partial reduction of V5+ and the formation of vacancy-related defects. ZIBs utilizing the EP-AVNF cathode exhibited significantly improved electrochemical performance compared to those with pristine AVNF and PEDOT-intercalated AVNF. The EP-AVNF cathode demonstrated superior rate capability of 255mAh g−1 even at high current densities of 20 A g−1. Moreover, it achieved a capacity retention of 99.2 % after 1,000 cycles at 10 A g−1, along with high energy and power densities. This study indicates that the simultaneous intercalation and polymerization of PEDOT:PSS within the AVNF interlayer using the sonochemical method optimizes both structural and electrical characteristics with high efficiency, providing an efficient route for achieving high-rate and long-cycle ZIBs.
This study establishes total internal reflection fluorescence (TIRF) imaging as a diagnostic method for investigating shock waves generated by collapsing laser-induced cavitation bubbles near a solid–liquid interface. TIRF was combined with synchronized short-pulse transillumination to capture both near-wall shock signatures and conventional bubble dynamics. A temperature-compensating Rhodamine 6G/Rhodamine B mixture made fluorescence variations primarily sensitive to density- and refractive-index changes. By tuning the laser incidence angle relative to the critical angle, the evanescent-field depth and density sensitivity were controlled, enabling robust detection of shock-wave footprints at the wall. Bubbles of 1-1.5 mm radius at moderate stand-off distances γ=1.0–1.6 were examined. The second collapse consistently produced the strongest shock activity, and the shock-originating event was observed to lead to microcrack formation. During the second collapse, the shock velocities of 1490–1971 m/s corresponded to peak pressures of 2.6–460 MPa. To our knowledge, this is the first fluid-dynamic measurement to provide physically reasonable pressure estimates for the second-collapse cavitation shocks at moderate stand-off distances, showing that the damage-producing shocks can reach or exceed the yield strength of technically relevant steels.
Using sonochemistry to synthesize hierarchical faujasite-type zeolites could offer a promising alternative to traditional alkaline-solution manufacturing. This approach could eliminate the need for costly and often hazardous reagents, thereby lowering production expenses and supporting green chemistry initiatives. Unlike conventional zeolite hierarchization, this innovative method could replace alkaline desilication of microporous zeolites entirely with ultrasonic pretreatment of the gel, followed by hydrothermal crystallization of the zeolite product. Selecting faujasite from over 260 possible zeolite structures highlights its broad utility in the chemical industry. The synthesized systems were analyzed for crystallinity, structure, Si/Al ratio, chemical states of silicon and aluminum, morphology, and acidity. Results showed that increasing ultrasound exposure time led to smaller crystallites and reduced microporosity, resembling effects obtained via standard alkaline desilication of parent microporous zeolites. Hence, it could be concluded that the sonicated zeolites were hierarchical materials at first sight. Nevertheless, significant drops in microporosity, accompanied by distinct fragmentation and a relatively low drop in Si/Al ratios, suggested existing interparticle voids rather than intracrystalline mesopores and macropores. Therefore, the sonicated materials reported in this work can be described as seemingly hierarchical faujasites. Furthermore, the sonicated faujasites exhibited high sensitivity to further modification, prompting further optimization studies, including zeolite structures with higher starting Si/Al ratios
Ambient pressure variations alter cavitation bubble dynamics, thereby affecting cavitation erosion on solid boundaries and the efficiency of aeration-based mitigation. In this study, the cavitation erosion mitigation efficiency and underlying mechanisms of entrained air bubbles in gas–liquid two-phase flow under varying ambient pressures were systematically investigated by combining macroscopic investigation and mesoscopic analysis. Ultrasonic cavitation experiments were conducted at ambient pressures of 55–95 kPa to quantify the erosion mitigation characteristics of aeration. The results showed that, under aerated conditions, the eroded-area ratio, pit depth, mean pit volume, cumulative mass loss and the erosion rate all decrease monotonically with decreasing ambient pressure, while the mitigation efficiency of aeration increases correspondingly. To elucidate the underlying mechanism, corona discharge system was employed to generate cavitation bubbles, enabling direct observation of the air bubbles interaction with cavitation bubbles. It was found that air bubbles significantly reduced the maximum velocity of microjet and attenuating the intensity of shockwaves impinging on the wall. Furthermore, both the maximum microjet velocity and the shockwave intensity decreased with decreasing ambient pressure under aerated conditions. The macroscopic trends in cavitation erosion mitigation of aeration and the mesoscopic effects of air bubbles on cavitation bubble dynamics together reveal the underlying mitigation mechanisms. They explain how aeration reduces cavitation erosion on solid boundaries exposed to high-speed water flow under high-altitude, low atmospheric pressure conditions. These findings offer theoretical support for applying aeration-based cavitation erosion mitigation in such conditions
A hydrodynamic cavitation/ultraviolet (HC/UV) platform was developed to systematically compare the oxidant-dependent degradation of tetracycline (TC) using hydrogen peroxide (H2O2) and peroxydisulfate (PDS) as oxidants. Cavitation visualization revealed that increasing the inlet pressure enhanced cavity growth and intensified cloud shedding, while TC removal by HC alone was highest at 0.35 MPa within the tested range. Under identical conditions, PDS exhibited a stronger response to binary process coupling than H2O2, with the UV/PDS system showing the highest synergistic index, while the HC/UV/PDS system showed the highest apparent rate constant. Following optimization of oxidant dosage and initial pH, HC/UV/H2O2 and HC/UV/PDS achieved TC removal efficiencies of 98.18% and 96.96%, respectively, within 60 min. The H2O2-assisted system performed more effectively under acidic conditions and exhibited a lower electrical energy per order (EEO) value of 126.52 kWh m−3 order-1 than the PDS-assisted system (143.28 kWh m−3 order-1), indicating slightly more favorable energy performance under the selected conditions. In contrast, the PDS-assisted route demonstrated broader pH adaptability. Scavenger experiments and UHPLC-HRMS/MS analysis indicated oxidant-dependent oxidation behavior. Tentative identification of transformation products suggested that TC degradation predominantly proceeded through oxygenation, side-chain modification, dealkylation, partial skeleton cleavage, and fragmentation. Predictions using the Toxicity Estimation Software Tool indicated that most transformation products exhibited lower estimated acute aquatic toxicity than TC, whereas developmental toxicity and mutagenicity varied with endpoint and product structure. These findings demonstrate that oxidant selection plays a critical role in governing process synergy, degradation pathways, toxicity evolution, and energy efficiency in HC/UV-based advanced oxidation systems, providing valuable insights for the treatment of refractory antibiotic-containing wastewater
A physically motivated Langmuir-Freundlich loading-response framework was formulated to describe the sonochemical degradation of nonvolatile organic contaminants in water. Acoustic cavitation was represented as a heterogeneous oxidative microenvironment in which contaminant degradation depends on apparent occupation of the bubble-liquid interfacial region and the finite oxidative capacity generated under fixed operating conditions. The framework was evaluated using naphthol blue black (NBB) and furosemide as chemically distinct nonvolatile contaminants. For NBB, increasing the initial concentration from 3 to 120 mg/L increased the initial degradation rate from 0.22268 to 2.1502 mg/L·min, while the 30-min removal efficiency decreased from 100 % to 43.46 % and the net H2O2 formation rate decreased from 5.4794 to 3.9161 μmol/L·min. Initial-rate calibration gave rmax = 3.8324 mg/L·min, KLF = 1.1298 × 10-2 L/mg, and n = 0.8256. To reduce parameter redundancy, all concentration-time profiles for each compound were described using four global parameters, r0,ref,T, βT, KLF,T, and nT, without concentration-specific fitted coefficients. The calibration RMSE values were 0.0196 for NBB and 0.0399 for furosemide. Blocked leave-one-concentration-out validation gave pooled RMSE values of 0.0391 and 0.0566, respectively. For NBB, 30-min removal measurements at 7, 10, 40, and 120 mg/L, which were excluded from time-resolved parameter estimation, were calculated with an RMSE of 1.79 percentage points. Comparison with simpler formulations showed that the loading-dependent pseudo-first-order model gave the lowest cross-validated RMSE for NBB, whereas the classical Langmuir and Langmuir-Freundlich formulations gave comparable cross-validated performance for furosemide. Parameter confidence intervals and covariance-based correlation analysis identified strong compensation among the initial-rate parameters but lower correlations in the four-parameter time-resolved formulation. The fitted coefficients are therefore interpreted as condition-specific apparent descriptors rather than direct measurements of interfacial adsorption, radical flux, or molecular cooperativity. The framework provides a reduced-order tool for interpolation and treatment-time calculations within a calibrated operating domain, but application to other compounds, reactors, or solution matrices requires recalibration and independent validation.
Oral astringency remains a major challenge limiting consumer acceptance of functional fermented beverages. Conventional mitigation strategies often reduce astringency at the expense of bioactive polyphenols, highlighting the need for non-destructive quality improvement approaches. In this study, low-power ultrasound-assisted fermentation (20 kHz, 240 W, 16.68 min/day) was applied to Kombucha, and the underlying mechanisms of astringency alleviation were investigated through integrated physicochemical characterization, metagenomic analysis, and temporal data modeling. Ultrasound significantly reduced sensory astringency and saliva-protein precipitation (OD650, p < 0.05) by Day 7 while preserving monomeric catechins, thereby maintaining antioxidant potential. Small-angle X-ray scattering (SAXS) and spectroscopic analyses revealed that ultrasound promoted the accumulation of water-soluble polysaccharides (1.69 mg/mL on Day 7, p < 0.01), which acted as macromolecular steric barriers and modified the aggregation behavior of polyphenol-salivary protein complexes. Consequently, the radius of gyration (Rg) increased to 608.67 nm, suppressing the formation of large aggregates associated with astringency perception. Furthermore, temporal machine-learning and time-lagged correlation analyses indicated that the reduction in astringency was associated not with increased abundance of Komagataeibacter intermedius, but with upregulated specific metabolic activity during the early fermentation stage. This early-stage metabolic adaptation was strongly associated with subsequent polysaccharide accumulation and sensory improvement. The findings suggest that low-power ultrasound can modulate microbial metabolic activity without altering microbial community structure, thereby influencing polysaccharide biosynthesis and colloidal interactions during fermentation. These results provide new insights into the biological and physicochemical mechanisms underlying ultrasound-assisted fermentation.
This study investigated the effects of ultrasonication (US, 20 kHz at 600 W for 30 min) applied at different postmortem stages, including pre-rigor (0.5 h) and post-rigor (24 h), on beef flavor characteristics during subsequent aging, and further elucidated its underlying mechanisms through integrated metabolomics. Sensory evaluation and electronic nose analyses demonstrated that pre-rigor US treatment significantly altered flavor profiles and enhanced overall acceptability compared with post-rigor US and non-US control (CON) groups. Further analysis revealed that beef subjected to pre-rigor US exhibited the highest abundance and diversity of volatile organic compounds, particularly characterized by 1-octen-3-ol, octanal, and 2-pentylfuran. Furthermore, abundant lipid molecules (e.g., phosphatidylethanolamine (PE), phosphatidylinositol (PI), and lysophosphatidylcholine (LPC)), along with enriched pathways in glycerophospholipid and nucleotide metabolisms, were typically identified in US-treated beef, particularly pre-rigor US. These critical precursors and metabolic pathways were primarily responsible for the superior flavor performance observed. Collectively, these findings demonstrated pre-rigor US technology as a potential strategy for improving beef flavor profiles during postmortem aging.
Faba bean protein isolate (FPI) is a promising plant-based protein ingredient; however, its compact molecular structure restricts its functional performance and bioactive potential. The effects of heat treatment (H-FPI), ultrasonication (U-FPI), and sequential thermosonication (UH-FPI) on the structural characteristics, techno-functional properties, and hypocholesterolemic activity of FPI were investigated in vitro and in vivo. Conformational changes of the protein matrix induced by ultrasound and thermosonication cause a decrease in the surface hydrophobicity, an increase in protein digestibility, and an improvement in functional properties over a wide range of pH. The in-vitro studies revealed that structural modification was also effective in improving the biological activity; in particular, the degree of hydrolysis was enhanced from 8.02 ± 2.62% (FPI) to 21.72 ± 2.25% (UH-FPI), while the micellar inhibition of cholesterol was enhanced from 23.4 ± 1.13% (FPI) to 48.5 ± 0.63% (UH-FPI) and higher HMG-CoA reductase inhibitory activity from 84.17 ± 2.65% (FPI) to 58.79 ± 3.52% (UH-FPI) indicating its potential in inhibiting intestinal cholesterol absorption and cholesterol biosynthesis. Furthermore, in vivo studies using high-fat (HF) diet-fed hamsters showed that UH-FPI improved the serum lipid profile and cholesterol metabolism-related proteins. The expression analyses further confirmed that UH-FPI upregulated the expression of cholesterol efflux-related proteins (ABCG5 and ABCG8), hepatic cholesterol metabolism regulators (LXR-α, CYP7A1, and LDL-R), and downregulated the expression of the intestinal cholesterol uptake-related protein NPC1L1 upon normalization with the HF group. The results indicate that thermosonication could be used to alter faba bean protein’s structure and modulate cholesterol metabolism, leading to improved functional and hypocholesterolemic properties, making it a suitable functional food ingredient for the promotion of cardiovascular health.
Ultrasonic treatment is an effective strategy for modifying protein structure. However, the accompanying generation of reactive oxygen species (ROS) inevitably induces protein oxidation and polyphenol degradation, compromising the functional performance of protein-polyphenol complexes. This study combined weakly basic electrolysed water (WBEW) with ultrasonic treatment to investigate its protective effects on the complexation between Antarctic krill protein and gallic acid (GA), as well as the structural and functional properties of the resulting complexes. WBEW effectively quenched ultrasound-generated •OH, reducing •OH levels from 4.36 to 3.02 μmol/L after 40 min of ultrasonication. Consequently, WBEW significantly suppressed protein carbonylation and sulphydryl loss and notably enhanced GA retention. A maximum binding efficiency of 34.8% was achieved at 20 min of ultrasonication in WBEW, corresponding to optimal particle size reduction (202.3 nm), improved solubility, and superior surface hydrophobicity. Fourier-transform infrared and fluorescence spectroscopy revealed that WBEW alleviated ultrasound-induced secondary and tertiary structural perturbations, maintaining more ordered conformations. The WBEW-20 complex exhibited significantly increased emulsifying activity (40.3 m2/g) and emulsifying stability indices, enabling the formation of high-internal-phase emulsions with uniform droplet size and thick interfacial layers. Moreover, emulsions stabilised by the WBEW-20 complex demonstrated remarkably lower peroxide (20.1 mmol/kg) and malondialdehyde (4.34 mmol/kg) values after 11 days of storage than the controls, along with superior thermal and ultraviolet oxidation resistance. These findings establish WBEW-assisted ultrasound treatment as a promising modification strategy for upgrading marine protein-polyphenol complexes with enhanced emulsifying and antioxidant functionalities for application in oxidation-sensitive food systems.
This study aimed to efficiently valorize protein resources from Juglans sigillata D. by employing ultrasound-shear-assisted enzymatic hydrolysis to generate α-glucosidase-inhibitory peptides. The process parameters were optimized using response surface methodology, and the structural basis underlying this enhanced inhibitory activity was further elucidated through multiscale structural characterization and molecular docking analysis. The optimal conditions were determined as follows: ultrasound treatment time of 21 min, ultrasonic power of 400 W, shear speed of 12000 r/min, and enzyme loading of 12 KU/g. Under these conditions, the α-glucosidase inhibition rate of the hydrolysate reached 54.38 ± 0.77 %, which was significantly higher than that obtained by enzymatic hydrolysis alone, with the latter showing an inhibition rate of 45.82 ± 3.28 % (p < 0.05). Structural analyses indicated that the combined ultrasound-shear treatment modified the conformational structure and increased the surface hydrophobicity of walnut protein, potentially enhancing protease accessibility and facilitating the release of α-glucosidase-inhibitory peptides. In total, 4492 peptides were identified by LC-MS/MS, from which 20 candidate peptides were prioritized using a BIOPEP-aided, two-stage in silico workflow. Molecular docking was subsequently used to compare the predicted binding modes and docking scores of selected peptides with α-glucosidase. The peptides FFPGSP, FGPSQPF, and APSKDAPMF were synthesized and experimentally validated. Their IC50 values were 1745, 5393, and 4090 μM, respectively. These findings show that combining peptide identification, bioinformatics screening, molecular docking, and in vitro validation can help facilitate the preliminary discovery and selection of α-glucosidase-inhibitory peptides. This study provides a basis for the high-value utilization of J. sigillata protein and the development of natural peptides with potential α-glucosidase-inhibitory activity.
A novel ultrasound-assisted synbiotic microencapsulation system was developed using gum arabic, reconstituted skim milk, and prebiotic oligosaccharides (fructooligosaccharides, xylooligosaccharides, and galactooligosaccharides) for the delivery of Clostridium butyricum. Ultrasound significantly improved viable-cell recovery, reaching 93.17 % in the fructooligosaccharide formulation (p < 0.05). Structural analyses indicated that oligosaccharide type and ultrasound treatment affected particle morphology, water mobility, protein secondary structure, and the solvent-extractable fractions related to intermolecular interactions. Ultrasound treatment improved the environmental stress tolerance of the freeze-dried formulations, increasing 60-day storage survival by 10.4 %, 6.9 %, and 16.6 % in the control, XOS, and GOS formulations, respectively, and significantly reducing viability loss during separate gastric, intestinal, and bile-salt tolerance tests (p < 0.05). Among the tested oligosaccharides, the XOS-containing formulations showed the most balanced overall performance. MC-XOS showed the highest survival after heat treatment (51.3 %) and retained a survival rate of 27.5% after 3 h of separate exposure to simulated gastric fluid, whereas MC-XOS-US maintained the highest survival after 60 days of storage at 4 °C (60.87 %) (p < 0.05). These findings provide an effective strategy for developing stable delivery systems for anaerobic probiotics.
Ultrasonic cavitation, as a representative non-thermal process intensification technology, has attracted increasing attention in the field of food processing in recent years. However, most existing studies have primarily focused on evaluating the improvement of processing performance in specific food systems, while the intrinsic relationship between cavitation behavior and structural responses of food matrices remains insufficiently understood. This knowledge gap has hindered the further transition of ultrasonic technologies from laboratory-scale investigations to industrial applications. Following the logical framework of “ultrasound-induced cavitation–cavitation-driven processing effects–food matrix responses–engineering applications”, this review systematically summarizes recent advances in the application of ultrasonic cavitation for the extraction of natural bioactive compounds, food safety control, interfacial structure regulation, macromolecular modification, and complex food processing. Particular emphasis is placed on the distinct roles of mechanical and sonochemical effects in different food matrices. It is highlighted that the performance of ultrasonic processing cannot be determined solely by individual operating parameters, but rather depends on the synergistic interaction between cavitation characteristics and the inherent properties of food systems.
This study evaluated the effect of cylindrical focused ultrasound to improve the multifunctionality of liquid egg white and investigated the underlying protein structural changes associated with these functional improvements. Liquid egg white was treated at 380 kHz and 100 W for 0, 10, 20, or 30 min at 25 °C. Compared with the untreated control, 20 min of treatment significantly enhanced the foaming and emulsifying properties of egg white (p < 0.05), whereas no significant differences were observed between the 20 and 30 min treatments (p > 0.05). After 20 min of treatment, foaming capacity and foaming stability increased from 34.45 % to 57.78 % and from 71.30 % to 88.66 %, respectively (p < 0.05). Similarly, the emulsifying activity index and emulsifying stability increased from 20.86 to 31.77 m2/g and from 25.68 to 53.68 min, respectively (p < 0.05). These improvements were accompanied by reduced particle size, increased absolute zeta potential, and enhanced surface hydrophobicity, whereas SDS-PAGE profiles, carbonyl content, pH, and total free amino acid content remained unchanged. In addition, 20 min of treatment significantly increased the hardness and chewiness of heat-induced egg white gels (p < 0.05), without changing cooking yield, cooking loss, or whiteness index (p > 0.05). In conclusion, cylindrical focused ultrasound treatment for 20 min improved the foaming, emulsifying, and heat-induced gel texture properties of egg whites while maintaining protein structural integrity, demonstrating its potential as an effective controlled-processing method for egg white-based food applications.
This study systematically compared ultrasound-assisted electrolyzed water extraction (UAEWE), ultrasound-assisted extraction (UAE), traditional acid extraction (AE), and commercially available hawthorn pectin (CHP) in terms of pectin yield, physicochemical properties, structural characteristics, and antioxidant activity. The objective was to evaluate the feasibility of UAEWE as a sustainable alternative for hawthorn pectin production and explore its potential applications. Results indicated that UAEWE-extracted pectin achieved the highest yield (7.21 ± 0.13%) and galacturonic acid (GalA) content (87.35 ± 0.37 g/100 g), significantly surpassing UAE (5.96 ± 0.06%; 82.28 ± 0.49 g/100 g) and AE (4.53 ± 0.15%; 76.08 ± 0.96 g/100 g). However, UAEWE-extracted pectin exhibited lower esterification degree (63.13 ± 0.08%), weight-average molecular weight (223.92 ± 4.22 kDa), and particle size (3.56 ± 0.45 μm) than the other samples. Monosaccharide composition analysis revealed similar sugar profiles among all samples, although relative proportions differed. Microstructural characterization showed that UAEWE-extracted pectin possessed a highly porous architecture, consistent with its superior extraction yield. FTIR and NMR analyses confirmed no significant structural alterations among the pectin samples. Rheological measurements demonstrated that UAEWE-extracted pectin exhibited the lowest apparent viscosity at 1% concentration, pH 3, and low shear rates. Moreover, UAEWE-derived pectin showed enhanced antioxidant activity compared with UAE, AE, and CHP samples. These findings highlight UAEWE as a promising extraction strategy for hawthorn pectin, offering reduced acid usage, cost-effectiveness, and environmental sustainability. The resulting pectin, characterized by high GalA content and antioxidant capacity, shows potential for bioactive compound encapsulation and functional food applications.
Droplet levitation in air represents a promising containerless, plastic-free reaction vessel for chemical biology. In this study, we show that dimethyl sulfoxide (DMSO), a hygroscopic solvent that absorbs moisture from air, is a suitable additive for long-term levitation and for copper-catalyzed alkyne-azide cycloaddition reactions in levitated droplets. When the volume of solvent mixtures composed of water and water-miscible organic solvents was precisely monitored, the evaporation of DMSO-containing aqueous mixtures was negligible, and their volume increased under high humidity. Furthermore, the click reaction in a DMSO-water mixture under levitation proceeded faster and with higher yield than the same reaction performed in a shaken tube. Together, these results suggest that ultrasonic levitation has the potential not only to alter conventional experimental workflows in chemical biology, but also to enable capture of moisture from ambient air.
The conversion of all-carbon backbone polymer waste into valuable carbon materials represents an ideal route to address polymer pollution and advance resource circularity. However, conventional degradation methods are challenging to deconstruct stable all-carbon backbones and trigger molecular configuration transformation. Here, we report a one-step degradation-upcycling strategy based on highly localized intense ultrasonic cavitation (IUC) generated by a spherical cavity focused ultrasound transducer (SCUT) operating at 650 kHz under a high hydrostatic pressure of 10 MPa. Rapid C-C backbone cleavage and in situ conversion of water-soluble all-carbon backbone polymers (including polyvinyl alcohol (PVA), polymethacrylic acid (sodium salt) (PMAA), and polyvinylpyrrolidone (PVP)) into functional carbonized polymer dots (CPDs) have been realized. Taking PVA as an example, a near-complete depolymerization with maximum molecular weight reduction of 96.45 % was achieved. Meanwhile, the generated CPDs exhibit tunable fluorescence and excellent antibacterial properties, realizing the transformation from polymer waste to value-added resources. Mechanistic analysis revealed that under the highly concentrated shock waves, high temperatures, and free radicals generated in IUC, degradation-upcycling of these polymers was achieved through a cascade strategy of 'mechanical scission - radical oxidation - graphitization'. Observations of rapid degradation and transformation of the all-carbon backbone to sp2 graphitic carbon derived from the IUC under high hydrostatic pressure have broadened understanding of sonochemical polymer processing and shaped a new way for polymer waste treatment, showing significant scientific value and application potential.
Germination represents a recognized strategy for improving the nutritional profile and promoting the enrichment of bioactive constituents in cereal crops. However, the regulatory mechanisms through which physical treatments such as ultrasound influence metabolic processes during germination remain insufficiently understood. This study investigates the effects of ultrasound-assisted germination (50 kHz, 240 W, 30 min) on amino acid and carbohydrate metabolism in sorghum while employing integrated metabolomic and transcriptomic approaches. Total protein and starch contents decreased during germination, with starch content in fully germinated ultrasound-treated grains (FG + U) declining to 344.27 mg/g. Protease and α-amylase activities increased during germination and were further improved by ultrasound treatment, suggesting increased mobilization of storage reserves during germination. Metabolomic analysis identified 110 amino acids and 49 carbohydrates as differentially accumulated metabolites under ultrasound treatment at the fully germinated stage, including six essential amino acids and increased D-glucose levels. Transcriptomic analysis revealed 7,791 genes shared between germination-related and ultrasound-responsive differentially expressed genes (DEGs). These genes were significantly enriched in metabolic pathways, including alanine, aspartate, and glutamate metabolism; glycolysis/gluconeogenesis; and the pentose phosphate pathway. Based on the Weighted gene co-expression network analysis (WGCNA)-derived gene modules, transcription factor-target gene network analysis further identified three highly connected transcription factors, including bHLH137 (LOC8060932), R-S (LOC8056590) and EIL1 (LOC110434014), as candidate hub transcription factors associated with amino acid and carbohydrate metabolism. These results provide systems-level insights into the transcriptional and metabolic responses associated with ultrasound-assisted germination and identify candidate regulatory components for future functional investigation.
Physical modification provides a sustainable strategy for tailoring rice flour functionality; however, the role of treatment sequence in dual physical modification remains insufficiently understood. This study investigated the sequence-dependent effects of ultrasonic treatment (UT) and annealing (ANN) on the multiscale structure, hydration behavior, pasting properties, water dynamics, rheological performance, and gel-forming ability of indica rice flour from Taichung Sen 17. Savory rice pudding (wa gui) was further used as a proof-of-concept application model. The ANN–UT sequence caused the greatest structural disruption, as indicated by the lowest median particle size (D50 = 8.83 μm), relative crystallinity (15.23%), gelatinization enthalpy (0.25 J/g), peak viscosity (2068.66 cP), and final viscosity (3392.33 cP). These changes were accompanied by restricted swelling, higher water mobility, and weaker gel formation. On the contrary, the UT–ANN sequence retained greater structural continuity and reassociation capacity, as reflected by higher D50 (10.43 μm), relative crystallinity (16.15%), gelatinization enthalpy (0.65 J/g), peak viscosity (4273.66 cP), and final viscosity (6913 cP). UT–ANN also promoted stronger water confinement and firmer wa gui gel formation. These findings indicate that UT–ANN and ANN–UT represent distinct path-dependent routes of modification rather than interchangeable dual treatments. Sequence control may therefore provide a non-chemical strategy for designing rice-based ingredients with tunable hydration, pasting, and gel-forming properties. Further molecular-level characterization and validation of applications are required to confirm the structural basis and practical feasibility of this approach.
The current study explored the effect of multifrequency ultrasonication (20, 40, 60 kHz, and their combinations) on germination, nutritional profile, techno-functional properties, and physical properties of tartary buckwheat. Relative to the non-ultrasonicated control group, tri-frequency ultrasonication at 20/40/60 kHz significantly improved water absorption by 88.66 %, increasing immobilized and free water availability to achieve a germination rate of 85 % at 48 hrs. This ultrasonication-assisted germination increased α-amylase, PAL (phenylalanine ammonia-lyase), PPO (polyphenol oxidase), and POD (peroxidase) activities by 1.63, 6.84, 4.69, and 5.09 folds, respectively. This metabolic modification augmented phenolic accumulation and antioxidant capacity by 55.53 % and 14.60 %, respectively. Additionally, these enzymatic variations facilitated the phytic acid mitigation (45.21 %) and reduced tannin synthesis by 19.19 %. Ultrasonication-assisted germination improved the techno-functional properties of germinated tartary buckwheat flour, as indicated by elevated water holding capacity (35.86 %), water absorption index (48.28 %), water solubility index (30.62 %), emulsifying capacity (49.33 %), and emulsifying stability (24.33 %), compared to germinated control at 120 hrs. Furthermore, the texture profile was positively influenced, with hardness, gumminess, and chewiness reduced by 37.30 %, 42.82 %, and 51.35 %, respectively. Similarly, E-nose analysis revealed an improved aroma profile, characterized by augmented retention of sulfur compounds linked to a nutty, distinctive flour aroma. Therefore, tri-frequency ultrasonication emerges as a viable pretreatment for optimizing the nutritional quality and techno-functional quality of germinated tartary buckwheat flour.
