Ultrasound Irradiation Power Research Articles

Green surfactant and circulating ultrasound coupling extraction of total flavonoids from Cynanchum auriculatum leaves: Parameter optimization, extraction mechanism, and HPLC-MS analysis

This study aimed to devise an integrated green surfactant and circulating ultrasound coupling extraction (GSCUE) approach for extracting the total flavonoids from Cynanchum auriculatum leaves. Single-factor optimization combined with a Box–Behnken design was used to determine the optimal technological conditions, which included an APG0814/MES amount of 5 % (w/v), extraction temperature of 46 °C, ultrasound irradiation power of 509 W, liquid–solid ratio of 30 mL/g, mixing speed of 1000 r/min, and extraction time of 50 min. Under these conditions, the extraction yield of the total flavonoids reached 7.83 mg/g. The HPLC-MS was applied to identify the flavonoid compositions in Cynanchum auriculatum leaves extract. The results showed that flavonoid composition included Gardenin B, Luteolin, Kaempferol, Quercetin, 4′-Methoxy-7-O-beta-D-glucopyranosyl-8,3′-dihydroxyflavanone, Astragalin, Spiraeoside, Rutin, and Kaempferol 3-gentiobioside. Further, to investigate the GSCUE mechanism, plant samples before and after extraction were analyzed by fourier transform infrared spectroscopy, scanning electron microscopy, and contact angle analysis. The results indicate that the functional groups, surface microstructure, and surface wettability of the plant samples all affect the yield of the target active ingredients. The hydrophilic group content on the plant sample surface after GSCUE treatment was higher compared to the case of the untreated samples. Additionally, there was evidence of surface structural collapse and shrinkage, increased surface roughness, and a decreased contact angle due to GSCUE treatment. These results highlight the greater surface wettability of the plant samples, faster solvent penetration, and an effective increase in the total flavonoid yield, indicating the synergistic effect of combining ultrasound with green surfactants for total flavonoid extraction. Overall, GSCUE technology provided a sustainable and efficient approach for extracting the total flavonoids from plant materials.

Microbiological interpretation of weak ultrasound enhanced biological wastewater treatment – using Escherichia coli degrading glucose as model system

The Escherichia coli (E.coli) degrading glucose irradiated by ultrasound irradiation (20 W, 14 min) was investigated as the model system, the glucose degradation increased by 13 % while the E.coli proliferation decreased by 10 % after culture for 18 h. It indicated a tradeoff effect between substrate degradation and cell proliferation, which drove the enhanced contaminants removal and excess sludge reduction in a weak ultrasound enhanced biological wastewater treatment. The enzymatic activities (catalase, superoxide dismutase, adenosine triphosphatases, lactic dehydrogenase, membrane permeability, intracellular reactive oxygen species and calcium ion of E. coli increased immediately by 12 %, 63 %, 124 %, 19 %, 15 %, 4-fold and 38-fold, respectively by ultrasound irradiation power of 20 W for 14 min. Furthermore, the membrane permeability of irradiated E. coli increased by 26 % even though the ultrasound stopped for 10 h. Additionally, pathways associated with glucose degradation and cell proliferation were continuously up-regulated and down-regulated, respectively.

Enhancing C-S and C-N bond formation with ultrasound assistance: lipase-catalyzed synthesis of 2,4-disubstituted thiazole derivatives from arylethanones and thioamides.

The present study explores an innovative approach for the efficient synthesis of 2,4-disubstituted thiazole derivatives, a class of compounds with diverse biological and pharmaceutical significance. This research presents lipase as a highly effective and environmentally friendly catalyst for thiazole synthesis. Under mild circumstances, the condensation of aryl ethenone, KBrO3, and thioamide is aided by using ultrasonic energy. Moreover, we harness the power of ultrasound irradiation to accelerate the reaction, reducing reaction times and improving product yields. The lipase-catalyzed, ultrasound-assisted synthesis presented in this study represents a greener and more sustainable alternative to traditional synthetic pathways for these important compounds, offering promising potential for applications in medicinal chemistry and drug development. This approach holds the promise of advancing the field of thiazole synthesis, contributing to more sustainable and efficient chemical processes.

Unveiling the Potential of Cavitation Erosion-Induced Heavy Crude Oil Upgrading

The application of ultrasonic waves in the processing of hydrocarbons is a new promising technology that has developed rapidly in recent years. However, the acoustic-induced cavitation erosion phenomenon is poorly studied. In this paper, a comparison study of cavitation erosion was carried out in water and oils with different viscosities produced from Ashal’cha and North Komsomol using an ultrasonic reactor operating at an industrial frequency of 20 kHz. The acoustic spectra obtained from hydrophones during the ultrasonic treatment of fluids can be characterized by using subharmonics of the main frequency and a continuous white noise level. Moreover, the cavitation erosion of aluminum foil under various ultrasound irradiation times and power levels was thoroughly investigated. It has been found that the process of ultrasonic cavitation has a less erosive impact on metal foil in oil due to its high viscosity. In addition, the formation of microflows in the oil phase, which also intensify the erosion process, is hindered. Cavitation erosion in the Ashal’cha oil sample exhibited a higher intensity compared to that in the North Komsomol oil sample. It was found that upon increasing ultrasound intensity in the case of the viscous (Ashal’cha) oil sample, cavitation stability was disrupted. In turn, this led to a reduction in the collapse energy of the cavitation bubbles. The results we obtained enable the assessment of cavitation erosion in crude oil and could be used to improve methodologies for monitoring and optimizing cavitation processes in crude oil.

Natural surfactant used as an additive in the homogenate-ultrasound-synergistic extraction of regaloside A and polysaccharides from Lilium lancifolium bulbs using Doehlert matrix design

In this study, 10 different natural surfactants were compared as additives for the simultaneous extraction of lipophilic regaloside A and water-soluble polysaccharides from tiger lily ( Lilium lancifolium Thunb.) bulbs by homogenate-ultrasound-synergistic extraction. Four significant factors that affect the yields of regaloside A and polysaccharides, including homogenate speed, ultrasound irradiation power, reaction temperature and ultrasound irradiation time, were screened by single-factor experiments and Plackett-Burman design and then optimized using Doehlert matrix design combined with a desirability function. The optimal extraction process conditions were obtained as follows: APG06 ( n -hexyl glucoside) surfactant concentration of 0.6%, homogenate speed of 20000 r/min, homogenate time of 6 min, liquid solid ratio of 20 mL/g, ultrasound irradiation power of 300 W, ultrasound irradiation time of 52 min, reaction temperature of 62.8 °C, and buffer and cavitation times of 1.5 s and 2.0 s, respectively. Under the optimal extraction conditions, regaloside A and polysaccharides yields of 2.797 ± 0.084 mg/g and 0.493 ± 0.016 g/g are obtained with relative standard deviations of 3.00% and 3.50%, respectively. The results of the method validation and comparison with the conventional method show that homogenate-ultrasound-synergistic extraction with APG06 as an additive is a green, efficient and energy-saving extraction method. Compared with the traditional extraction method, HUSE with APG06 as an additive is an effective method to extract regaloside A and polysaccharides from L. lancifolium bulbs. This study provides a reference for the development of green low carbon natural product extraction process. • Use homogenate-ultrasound-synergistic extraction of regaloside A and polysaccharides. • Alkyl polyglucoside was first added to extract phenolic acid glycerides (regaloside A). • 0.6% n -hexyl glucoside was chosen as the extraction additive. • Use combination of Plackett-Burman design and Doehlert matrix design. • Alkyl polyglucoside has obvious advantages on yield and safety compared with ethanol.

Texture/morphology evolution of CeZrO/Al2O3 nanocatalyst via sono-precipitation design for preferential oxidation of carbon monoxide: influence of ultrasound irradiation power

A series of CeZrO/Al2O3 nanocatalysts were synthesized via sono-precipitation method for utilization in oxidation of CO. The XRD results showed lower intensity of active phase peaks as the sonication power increased showing higher dispersions. SEM and TEM images showed the destruction of large particle agglomerates and superior dispersion of the CeZrO particles both on the surface and into the depth of support. BET-BJH results showed that the low surface area and pore volume of the CeZrO oxide approaches the alumina's area and higher pore volume by increasing the sonication power which reached 111 m2/g in 90 W sonicated nanocatalyst. The catalytic performance results with three different CO concentrations of 1, 2 and 4% proved the effectiveness of the ultrasound energy in successful conversion of the carbon monoxide in the gas stream. The 90 W treated sample reached the 98% CO conversion at 250 ºC and full conversion at 275 ºC.

Influence of ultrasound irradiation power on surface design of CaO nanoparticles over secondary carbon-templated meso designed ZSM-5 for biofuel production from vegetable oil

A series of potential bifunctional basic/acidic CaO over hierarchical ZSM-5 nanocatalysts were synthesized and investigated in biofuel production. Secondary hard templating was applied on the ZSM-5 support by carbonaceous charcoal particles in order to increase the pore size in favour of better diffusion of the large triglyceride molecules. The ultrasound irradiation was also applied with three different powers on impregnation of CaO active phase and its effect on well dispersing the particles was investigated. FESEM images showed high distributed and smaller particles on the surface of highly sonicated catalyst compared to the non-sonicated sample and BET-BJH results confirmed the opening of the pores and therefore size and volume increase by sonication. TPD-CO2 results indicated that both secondary templating and sonication have increased the strong basic sites. The particles were also smaller and less agglomerated due to sonication as observed in TEM images. Catalytic performance tests also confirmed the effective role of secondary charcoal templating on the conversion of oil as well as the positive influence of ultrasound irradiation. Sonicated nanocatalyst was also more stable after five times of reusability tests in transesterification of sunflower oil.

Polyethylenimine (PEI)-modified poly (lactic-co-glycolic) acid (PLGA) nanoparticles conjugated with tumor-homing bacteria facilitate high intensity focused ultrasound-mediated tumor ablation

The acoustic propagation characteristic of ultrasound determines that the energy of ultrasound beam will decrease with the increase of its propagation depth in the body. Similarly, the energy of High Intensity Focused Ultrasound (HIFU) will be attenuated with the increase of HIFU propagation depth in the body. Ensuring sufficient ultrasound energy deposition in the HIFU ablation region for tumor ablation is usually achieved by increasing the ultrasound irradiation power or prolonging the ultrasound ablation time. However, these two methods may damage the normal tissue adjacent to the HIFU ablation region. Herein, we constructed the nanoparticles conjugated with tumor-homing bacteria as the biological tumor-homing synergist to facilitate HIFU-mediated tumor ablation avoiding the potential safety risk. In our strategy, Bifidobacterium bifidum (B.bifidum) was selectively colonized in the hypoxic region of solid tumors after been injected into 4T1 breast cancer bearing-BALB/c mice via the tail vein due to its anaerobic growth characteristic. The amount of B. bifidum with negative surface potential in the hypoxic region of solid tumors was increased by its anaerobic proliferation. Polyethylenimine (PEI) -modified Poly (lactic-co-glycolic) acid nanoparticles loaded sodium bicarbonate (PEI-PLGA-NaHCO3-NPs) with positive surface potential injected into 4T1 breast cancer bearing-BALB/c mice via the tail vein displayed the tumor-homing ability by the electrostatic adsorption with B. bifidum colonized solid tumors. PEI-PLGA-NaHCO3-NPs could release NaHCO3 to produce carbon dioxide (CO2) as cavitation nuclei inside the acidic microenvironment of solid tumors. When HIFU irradiated solid tumors contained with more cavitation nuclei, the ultrasound energy deposition at the tumor region was increased to destroy the tumors more effectively. Meanwhile, the improved efficiency of HIFU-mediated tumor ablation reduced the dependence of the tumor ablation on the ultrasound energy dose, which improved the safety of HIFU-mediated tumor ablation to the non-targeted ablation tissue. This tumor-homing synergist shows the potential application value on the HIFU-mediated tumor ablation in the clinical.

Distinct advantages of using sonochemical over laser ablation methods for a rapid-high quality gold nanoparticles production

Gold nanoparticles (AuNPs) have numerous usage in various applications, primarily in chemical and biological sensing. There are also various methods of producing AuNPs. However, in some of those methods, removing excess reagents, including ions or residual surfactants, can be difficult and time-consuming, while the functionalization of AuNPs with other types of molecules can only be achieved at lower efficacy. In this report, the AuNPs were produced using a rapid and solvent-free sonochemical and laser ablation methods. Morphology, structure and the colloidal stability of AuNPs produced by the two methods were analyzed and compared. Results have shown that the purity, homogeneity and crystallinity of AuNPs produced using the sonochemical technique showed better characteristics than those acquired by the laser ablation method. AuNPs also demonstrated smaller particle sizes (22 nm), smooth surfaces with higher colloidal stability (50.7 mV). The findings indicate that ultrasound irradiation power improves the crystalline properties of AuNPs and inhibits their agglomeration. The sonochemical approach can, therefore, be used to produce AuNPs with better physicochemical characteristics compared to laser ablation methods.

Ultrasonic‐Assisted Preparation of Maize Starch–Caffeic Acid Complex: Physicochemical and Digestion Properties

AbstractAs an energy‐saving and effective physical method, ultrasound technologies are gaining research attention for the production of modified starches. Corn starch–caffeic acid complexes are prepared via ultrasound process, and the effect of ultrasound power on the physicochemical properties and in vitro digestion of the complexes is investigated. The results of Fourier‐transform infrared spectroscopy and the amount of complexes analysis indicate that ultrasound can help with the formation of starch–caffeic acid complexes, and the amount of caffeic acid in complexes depended on the ultrasound power. Scanning electron microscopy shows starch–caffeic acid complexes exhibit obvious dense network structure with increasing ultrasound power. X‐ray diffraction results indicate the presence of V‐type crystalline polymorph between starch and caffeic acid under high power of ultrasound irradiation. The starch–caffeic acid complexes can significantly inhibit the swelling power of starch granules at high temperature and increase the solubility of starch granules. Furthermore, the in vitro digestion of starch–caffeic acid complexes is estimated, and the result shows that the resulting complexes from ultrasound have lower digestion properties. Taken together, it is proposed that ultrasound technology is an effective method for preparation of starch complexes with potential as a functional food and drug delivery system.

Sono-solvothermal decoration of pore size controlled SAPO-34 by nano-ceria for green fuel production via esterification reaction

In this research, the SAPO-34 nanocatalyst has been improved in order to produce biodiesel as a green fuel. According to large molecules of free fatty acids (FFAs) and difficulty in the diffusion of these molecules through small pores of SAPO-34, the active charcoal secondary template was used to create meso and macro pores. Also, in order to increase acidic strength and density of active sites, CeO2 particles were accommodated to the structure of mesopores SAPO-34 by sono-solvothermal treatment and using ultrasound irradiation powers of 0, 100, 200 and 300 W. The synthesized catalysts were evaluated by FESEM, FTIR, TPD-NH3, HRTEM, XRD, and BET-BJH analyses. Results of characterization and reactor tests indicate that increasing the ultrasound irradiation power from 0 to 300 W in the synthesis stage has a significant effect on improving nanocatalysts properties and their performance in producing biodiesel, such that the conversion percentage in esterification reaction increased from 77 to 94%. The BET analysis showed, firstly, that using active charcoal leads to an increase of mean pore diameter of SAPO-34 from 0.5 to 3.4 nm, and secondly, that by using ultrasound irradiation power of up to 300 W, the pore volume in meso and macro range increases by 2.5 times. Results of the reactor test for the Ce/MSAPO-34 catalyst revealed that increasing the temperature, reaction time, and mole ratio of methanol to oil leads to an increase in conversion of oleic acid to biodiesel. Studying the kinetics of esterification reaction showed that using ultrasound irradiation powers of 100, 200, and 300 W increased the reaction rate by 20%, 30%, and 40%, respectively.

Ultrasound-Assisted Extraction of Taxifolin, Diosmin, and Quercetin from Abies nephrolepis (Trautv.) Maxim: Kinetic and Thermodynamic Characteristics.

Extraction behaviors of the 3 flavonoids taxifolin, diosmin, and quercetin have been investigated in Abies nephrolepis leaves and bark. The following operation parameters—ethanol volume fraction, liquid–solid ratio, temperature, ultrasound irradiation power and time, and ultrasound frequency—were varied to study their effect on the yield of the 3 flavonoids during extraction. The results showed that a low extraction efficiency occurred at 293.15 K due to slow kinetics, while the situation was significantly improved at 333.15 K. The kinetic data for the extraction yields of the 3 flavonoids achieved good fits by the first-order kinetic model. From the thermodynamic analysis results, we realized that the ultrasound-assisted extraction of taxifolin, diosmin, and quercetin from the leaves and bark of A. nephrolepis was a spontaneous and endothermic process in which the disorder increased (ΔG0 < 0, ΔH0 > 0, and ΔS0 > 0). According to the response surface methodology (RSM) analysis, under the optimal operation conditions (ethanol concentration of 50%, liquid–solid ratio of 20 mL/g, frequency of 45 kHz, extraction time of 39.25 min, ultrasound irradiation power of 160 W and temperature of 332.19 K), the total yield of the 3 flavonoids were 100.93 ± 4.01 mg/g from the leaves of A. nephrolepis (with 31.03 ± 1.51 mg/g, 0.31 ± 0.01 mg/g, 69.59 ± 2.57 mg/g for taxifolin, diosmin, and quercetin, respectively), and under the optimal operation conditions (ethanol concentration of 50%, liquid–solid ratio of 20 mL/g, frequency of 45 kHz, extraction time of 36.80 min, ultrasound irradiation power of 150 W and temperature of 328.78 K), 16.05 mg/g ± 0.38 mg/g were obtained from the bark of A. nephrolepis (with 1.44 ± 0.05 mg/g, 0.47 ± 0.01 mg/g, 14.14 ± 0.38 mg/g for taxifolin, diosmin, and quercetin, respectively), which were close to the prediction values.

Production of Sharp-Edged and Surface-Damaged Y2BaCuO5 by Ultrasound: Significant Improvement of Superconducting Performance of Infiltration Growth-Processed YBa2Cu3O7-δ Bulk Superconductors.

Growth and physical properties of bulk REBa2Cu3O7−δ (REBCO) superconductors fabricated by the infiltration growth (IG) method strongly depend on the initial size and morphology of the RE2BaCuO5 (211) particles. The present work details the novel method we developed for producing sharp-edged and surface-damaged 211 particles to be added to the REBCO bulks. We employed high-energy ultrasonic irradiation for pretreating the 211 particles and fabricated high-performance bulk single-grain YBa2Cu3O7−δ (YBCO) superconductors via the top-seeded IG process. Increasing the ultrasound irradiation power and time duration mechanically damaged the surface of the 211 particles, producing more fine and sharp edges. Systematic investigations of the microstructural properties of the final YBCO bulks indicated that the size and content of the 211 particles gradually decreased without any additional chemical doping. The effective grain refinement and improved interfacial defect densities enhanced the critical current density by a factor of two at 77 K and self-field as compared to a YBCO sample fabricated without any pretreatment. A maximum trapped field of 0.48 T at 77 K was obtained for a sample (20 mm diameter) with 211 particles treated for 60 min and 300 W ultrasound radiation. The effectiveness of the novel method is demonstrated by the superior performance of the YBCO bulk samples prepared as compared to bulk samples fabricated with the addition of Pt and CeO2. This method is novel, cost effective, and very convenient, maintaining high sample homogeneity, and is free of chemical contaminants as compared to other methods which significantly affect the properties of all REBCO bulk products grown by sintering, melt growth, and IG methods.

Environmentally superior cleaning of diatom frustules using sono-Fenton process: Facile fabrication of nanoporous silica with homogeneous morphology and controlled size.

Existing techniques for the preparation of silica structures from diatom cells include cleaning of frustules through baking at high temperature and oxidant cleaning using concentrated sulfuric acid, hydrogen peroxide, nitric acid, or sodium dodecyl sulfate (SDS)/ethylenediaminetetraacetic acid (EDTA). In this study, sono-Fenton (SF) process was examined to prepare nanoporous silica through cleaning diatom frustules, while preserving their structural features. Single colonies of Cyclotella sp. were cultivated in batch mode f/2-enriched seawater. Combination of Fenton process with ultrasonication was found to be more efficient than the sum of individual processes in the removal of organic compounds from Cyclotella sp. structure. The optimized amounts of operational parameters were determined as suspension pH of 3, diatom cell density of 4.8×105 cell mL-1, H2O2 concentration of 60mM, Fe2+ concentration of 15mM, ultrasound irradiation power of 400W and the temperature of 45°C. The results of energy-dispersive X-ray spectroscopy (EDX) and thermal gravimetry (TG) analyses proved that organic materials covering the cell wall were significantly removed from the frustules through SF process. Scanning electron microscopy (SEM) images showed that after SF treatment, silica nanostructures were produced having uniform pores less than 15nm in diameter. N2 adsorption-desorption isotherms demonstrated that almost non-porous structure of diatom frustules became mesoporous during removing the organic matrix. Lipids, amino acids, carbohydrates and organic acids or their oxidized products were identified using GC-MS analysis as the main organic compounds released from diatom cells to the solution after SF treatment. Treated frustules exhibited adsorption capability of 91.2mg/g for Methylene Blue, which was almost 2.5 times higher than that of untreated frustules (34.8mg/g).

Eco-friendly green synthesis of novel magnetic Fe3O4/SiO2/ZnO-Pr6O11 nanocomposites for photocatalytic degradation of organic pollutant

This study reports the successful sonochemical synthesis of novel Fe3O4/SiO2/ZnO-Pr6O11(Fe/Si/Zn–Pr6O11) nanocomposites using fructose as a green capping agent. The influence of various parameters containing capping agent, power and time of ultrasound irradiation was investigated to reach optimum morphology and size conditions. The products obtained were characterized by transmission electron microscopy (TEM), UV/Vis diffuse reflectance spectroscopy (DRS), Fourier transform infrared spectra (FT-IR), vibration sample magnetometer (VSM), scanning electron microscopy (SEM), energy dispersive X-ray microanalysis (EDS) and X-ray diffraction (XRD). The Fe3O4/SiO2/ZnO-Pr6O11 nanocomposites display remarkably enhanced photocatalytic activity towards rhodamine b degradation (89.6%) and Congo red (84.7%) under UV irradiation compared with the other products. The results illustrate that the photocatalytic efficiency of magnetic nanocomposites is very much higher than pure Pr6O11 nanostructures. Magnetic photocatalyst still has good stability after five successive runs. So, these recyclable nanocomposites can play a role in the treatment of both industrial and domestic contaminated water.

Efficient Homogenization-Ultrasound-Assisted Extraction of Anthocyanins and Flavonols from Bog Bilberry (Vaccinium uliginosum L.) Marc with Carnosic Acid as an Antioxidant Additive.

To explore the optimum conditions for the extraction of anthocyanins and flavonols from bog bilberry (Vaccinium uliginosum L.) marc on a single-factor experimental basis, a response surface methodology was adopted for this intensive study. The extraction procedure was carried out in a Waring blender and followed an ultrasonic bath, and the natural antioxidant carnosic acid was added to inhibit oxidation. The optimum extraction conditions were as follows: a volume fraction of ethanol of 70%, an antioxidant content of 0.02% (the mass of sample) carnosic acid, a liquid–solid ratio of 16 mL/g, a homogenization time of 3 min, a reaction temperature of 55 °C, an ultrasound irradiation frequency of 80 kHz, an ultrasound irradiation power of 200 W, and an ultrasound irradiation time of 40 min. Satisfactory yields of anthocyanins (13.95 ± 0.37 mg/g) and flavonols (3.51 ± 0.16 mg/g) were obtained. The experimental results showed that the carnosic acid played an effective antioxidant role in the extraction process of anthocyanins and flavonols with a green and safety guarantee.

The role of Diethanolamine as stabilizer in controlling morphology, roughness and photocatalytic activity of ZnO coatings in sonophotodegradation of methylene blue

ZnO thin films with various molar ratio of Diethanolamine were manufactured on the glass plates by using the sol-gel method and ZnO particles immobilized on glasses with easy and inexpensive dip-coating method. Effect of different Diethanolamine mole ratio of 0.5, 1, 1.5 and 2 on the morphology, roughness, crystalline structure and photocatalytic activity of ZnO coatings was studied by applying XRD, AFM, DRS, FESEM and FTIR analysis. The XRD patterns revealed that with increasing the Diethanolamine concentration crystalline size and peak intensity of ZnO decreased. AFM images showed that mole ratio of Diethanolamine had a great role in the ZnO coatings roughness so that samples with mole ratio 1 and 2 of diethanolamine had the best and the worst surface roughness, respectively. FESEM images of samples have good agreement with XRD and AFM analysis. According to the FTIR spectra of prepared samples the fingerprint region of ZnO is between 700–500 cm−1 which the intensity of peaks has been changed in each sample. Effect of different mole ratio of Diethanolamine on the photocatalytic activity of ZnO nanostructured films in sonophotodegradation of methylene blue under visible light irradiation in a batch photoreactor equipped by ultrasound probe. The best performance of photocatalyst was achieved by DZ2 content. Also, the effect of operating parameters such as pH, concentration of MB, various Ultrasound Irradiation Power and the number of photocatalytic coatings on sonophotodegradation of methylene blue on the activity of DZ2 coatings were evaluated. The results showed that the coatings with mole ratio 1 and 2 of Diethanolamine had the highest and the least photocatalytic performance.

Natural antioxidant of rosemary extract used as an additive in the ultrasound-assisted extraction of anthocyanins from lingonberry (Vaccinium vitis-idaea L.) pomace

The effects of natural antioxidant rosemary extracts with different carnosic acid concentrations (30%, 60%, and 90%) and of three synthetic antioxidants in the extraction of anthocyanins from lingonberry (Vaccinium vitis-idaea L.) pomace under ultrasound irradiation conditions were compared. The optimum extraction conditions were selected: antioxidant rosemary extract with carnosic acid of 30% (purity), 0.02% (carnosic acid to lingonberry pomace sample mass ratio); ethanol volume fraction, 40%; pH 1.5; liquid–solid ratio, 20 mL/g; ultrasound frequency, 80 kHz; ultrasound irradiation power, 170 W; reaction temperature, 55 °C; and ultrasound irradiation time, 35 min. Compared with traditional extraction techniques (no addition of rosemary extract), we obtained satisfactory yields of anthocyanins of 4.12 ± 0.18 mg/g (cyanidin-3-galactoside yield of 3.36 ± 0.14 mg/g, cyanidin-3-glucoside yield of 0.15 ± 0.01 mg/g and cyanidin-3-arabinoside yield of 0.61 ± 0.03 mg/g). The supplement of natural antioxidant rosemary extract was first added to inhibit the oxidation of anthocyanins, and the proposed natural antioxidant rosemary extract exhibited potential to replace synthetic antioxidants with greater security.

Modeling and optimization of ultrasound-assisted green extraction and rapid HPTLC analysis of stevioside from Stevia Rebaudiana

Stevioside is the major constituent of the Stevia Rebaudiana plant. The aim of this study is to appraise optimum procedure conditions for extraction of stevioside from Stevia Rebaudiana by Peleg’s mathematical methodology. Stevioside from dried leaves of Stevia Rebaudiana was extracted by means of probe type sonication system using glycerol as a green and generally recognized as safe (GRAS) solvent. High Performance Thin Layer Chromatography (HPTLC) was used as a very efficient, rapid and precise method for stevioside detection and analysis. Results demonstrated that the optimum conditions for ultrasound-assisted extraction (UAE) of stevioside from Stevia Rebaudiana are glycerol as solvent, temperature of 70 °C, plant to solvent proportion of 1:30, plant powder particle size of 0.075 mm, 200 W ultrasound irradiation power and 20 kHz ultrasound irradiation frequency. The comparing experimental results for Ceq of extracted stevioside with calculated values from Peleg’s mathematical model showed good and acceptable agreement. As a consequence, it was concluded that the ultrasound-assisted extraction is an efficient, fast, and economic method for extraction of stevioside from Stevia Rebaudiana in comparing with Soxhlet and maceration methods. Moreover, selected mathematical model displays the system with an acceptable accuracy which can predict the optimal conditions for extraction of stevioside those are close enough to experimental results.Practical Applications This investigation presented a mathematic model and experimental approach for the optimization of stevioside content of Stevia Rebaudiana using the ultrasound-assisted extraction and HPTLC analysis. Compared with the classic methods for optimizing of stevioside using the mathematic approaches or chemical experiments, the Peleg’s method is more precise and convenient. Moreover using ultrasound and HPTLC as extraction and analysis method, respectively, provides safer, rapid, and simple way for their stevioside extraction. Therefore, the method demonstrated in the present investigation could be used to extract the stevioside of Stevia Rebaudiana in food and beverage industries.

Ultrasonically-assisted mechanochemical synthesis of zinc aluminate spinel from aluminium-rich layered double hydroxide

An ultrasonically-assisted mechanochemical method was further improved to increase the yield of high-quality ZnAl2-LDH with carbonate interlayer anions. In the LDH formation, the rarely studied temperature, power and pulse character of ultrasound irradiation were investigated to determine the optimal parameters for the synthesis. The as-prepared samples were milled with varying the grinding frequency in order to convert the layered hydroxide structure into ZnAl2O4 spinel. This was the first time that ZnAl2O4 spinel formation was induced mechanochemically. The main method to identify the effects of ultrasonic and mechanochemical treatments was X-ray diffractometry; however, infrared spectroscopy, scanning electron microscopy, and thermal analysis were also applied to follow and compare the mechanochemically induced spinel formation to the more frequently used heat treatment.