Optimizing the synergistic effect of sodium hydroxide/ultrasound pre-treatment of sludge

Ultrasound (ULS), sodium hydroxide (NaOH) and combined ultrasound/NaOH pre-treatment were applied to pre-treat waste activated sludge and improve the subsequent anaerobic digestion. Synergistic effect was observed when NaOH treatment was coupled with ultrasound treatment. The highest synergistic Chemical Oxygen Demand (COD) solubilization was observed when 0.02M NaOH was combined with five minutes ultrasonication: an extra 3000 mg/L was achieved on top of the NaOH (1975 mg/L) and ultrasonication (2900 mg/L) treatment alone. Further increase of NaOH dosage increased Soluble Chemical Oxygen Demand (SCOD), but did not increase the synergistic effect. Nine and 18 minutes ultrasonication led to 20% and 24% increase of methane production, respectively; Whereas, 0.05M NaOH pre-treatment did not improve the sludge biodegradability. Combined ultrasound/NaOH (9 min+0.05 M) showed 31% increase of methane production. A stepwise NaOH addition/ultrasound pre-treatment (0.02M+ULS for 5 min+0.02M+ULS for 4 min) was tested and resulted in 40% increase of methane production using 20% less chemicals.     

Application of ultrasound in grape mash treatment in juice processing

Recently, application of ultrasound has attracted considerable interest as an alternative approach to traditional methods. In this study, response surface methodology (RSM) was used to optimize the conditions for grape mash treatment by ultrasound and by combination of ultrasound and enzyme. The results indicated that optimal conditions were the temperature of 74 °C and the time of 13 min for sonication treatment; and were the enzyme concentration of 0.05% and the time of 10 min for combined ultrasound and enzyme treatment. In comparison with traditionally enzymatic treatment, sonication treatment increased extraction yield 3.4% and shortened treatment time over three times; combined ultrasound and enzyme treatment increased extraction yield slightly, only 2%, but shortened treatment time over four times. After sonication treatment, enzymatic treatment increased extraction yield 7.3% and total treatment time of this method was still shorter than that of traditionally enzymatic treatment method. Besides, application of ultrasound improved the grape juice quality because it increased contents of sugars, total acids and phenolics as well as color density of grape juice.     

Effect of combined ultrasonic and enzymatic extraction technique on the quality of noni (Morinda citrifolia L.) juice

In order to obtain noni juice with high yield and good quality, the effect of combined extraction technique of enzymatic treatment (EZ) and ultrasonication (US) on the overall quality of noni juice was investigated. Moreover, the extraction performance of the EZ-US combined extraction technique was compared with that of EZ-based extraction and the US-based extraction. Response surface methodology (RSM) was designed to optimize the parameters of ultrasonic treatment, by taking consideration of the extraction efficiency, quality parameters and bioactive ingredients of noni juice. The results indicated that combined ultrasonic and enzymatic treatment achieved a synergistic effect on promoting the quality of noni juice. The maximum juice yield of 67.95 % was obtained under ultrasonication for 10 min at 600 W after enzymatic treatment (EZU). In addition, EZU-treated juice exhibited the highest contents of total phenolic and flavonoid, which were 148.19 ± 2.53 mg gallic acid/100 mL and 47.19 ± 1.22 mg rutin/100 mL, respectively, thus contributing to better antioxidant activity. Moreover, the EZU treatment significantly reduced the particle size of noni juice, and improved its suspension stability and rheological properties. FTIR results indicated that the treatments did not bring major changes in the chemical structure and the functional groups of compounds in noni juice. Therefore, EZU treatment can be successfully applied to the extraction of noni juice with better nutritional properties and overall quality.     

An ammonium sulfate/ethanol aqueous two-phase system combined with ultrasonication for the separation and purification of lithospermic acid B from Salvia miltiorrhiza Bunge

We studied the effect of ultrasonication extraction technology combined with ammonium sulfate/ethanol aqueous two-phase system (ATPS) for the separation of lithospermic acid B (LAB) from Salvia miltiorrhiza Bunge. According to the literature and preliminary studies, ammonium sulfate concentration, ethanol concentration, pH, ultrasonication power, ultrasonication time and the ratio of solvent-to-solid were investigated using a single factor design to identify the factors affecting separation. Taking into consideration a simultaneous increase in LAB recovery (R (%)) and partition coefficient (K), the best performance of the ATPS was obtained at 25 °C and pH 2 using ammonium sulfate 22% (w/w) and ethanol 30% (w/w). To keep the solvent-to-solid ratio at 10, response surface methodology was used to find the optimal ultrasonication power and ultrasonication time. Quadratic models were predicted for LAB yield in the upper phase. Optimal conditions of 572.1 W ultrasonication power and 42.2 min produced a maximum yield of LAB of 42.16 mg g⁻¹ sample. There was no obvious degradation of LAB with ultrasound under the applied conditions, and the experimental yield of LAB was 42.49 mg g⁻¹ sample and the purity was 55.28% (w/w), which was much higher than that obtained using conventional extraction. The present study demonstrated that ultrasound coupled with aqueous two-phase systems is very efficient tool for the extraction and purification of LAB from Salvia miltiorrhiza Bunge.     

The promoted hydrolysis effect of cellulase with ultrasound treatment is reflected on the sonicated rather than native brown rice

Brown rice is nutritionally superior to polished white rice, as it maintains a large content of external bran that involves a series of bioactive compounds. However, the presence of bran also restricts water diffusion and results in adverse quality of brown rice. In this work, ultrasound conditions were optimized for cellulase to improve its hydrolysis effect on rice bran, and combinations of enzymatic and ultrasound treatment in different manners were conducted on brown rice, to improve the textural attributes. The results showed significant improvements in the catalytic activity and efficiency of cellulase after ultrasonication at the optimal intensity of 1.67 W cm⁻³ and duration of 30 min, with the conformational variation of cellulase observed from the fluorescence spectra and circular dichroism (CD). Despite the enhanced activity of ultrasonicated cellulase, it leaded to a similar rice surface morphology and a comparable amount of released glucose, and equivalent textural parameters of brown rice treated by native cellulase. However, for the pre-sonicated brown rice, the ultrasonicated cellulase showed a significantly higher hydrolysis capacity than the untreated enzyme, suggesting the important influence of ruptured bran surface on amplifying the hydrolysis effect of cellulase. Compared to the successive ultrasound stimulation on both cellulase and brown rice, ultrasound-assisted cellulase treatment on brown rice produced less glucose from rice bran, but induced similar textural properties of brown rice, possibly resulting from the simultaneously promoting effect of ultrasonication on cellulase and water diffusion. Ultimately, this study highlighted that the mild rice surface rupture is a crucial factor to display the promoted hydrolysis effect of ultrasonicated cellulase on brown rice. Ultrasound-assisted cellulase treatment potentially provides an effective strategy to improve the edible quality of brown rice.     

Effects of ultrasound on the enzymatic degradation of pectin

Ultrasound-assisted enzymatic maceration (UAEM) has gained considerable interest in the fruit juice industry, owing to its potential to increase juice yield and content of polyphenols while simultaneously saving time and energy. In this study, the effects of UAEM (ultrasonic probe, 20 kHz, 21 W*cm⁻² and 33 W*cm⁻²) on pectin degradation in a continuous circulation system were investigated over 60 and 90 min. Main pectinolytic enzymes activities of (polygalacturonase, pectin lyase and pectin methylesterase) of a commercial enzyme preparation were examined for individual synergistic effects with US. Pectin hydrolysis by UAEM differed significantly compared to treatment with ultrasound or enzymes alone regarding the profile of degradation products compared to treatment with ultrasound or enzymes alone. Ultrasound fragmented pectin to less branched oligomers of medium molecular weight (Mp approx. 150 kDa), which were further degraded by pectinolytic activities. The low molecular weight fraction (<30 kDa), which is known to be beneficial for juice-quality by adding nutritional value and stabilizing polyphenols, was enriched in small oligomers of homogalacturonan-derived, rhamnogalacturonan I-derived, and rhamnogalacturonan II-derived residues. Synergistic effects of ultrasound application enhanced the effective activities of polygalacturonase and pectin lyase and even prolonged their performance over 90 min, whereas the effective activity of pectin methylesterase was not affected. Final marker concentrations determined by each enzyme assay revealed a considerable higher total process output after UAEM treatment at reduced temperature (30 °C) comparable to the output after conventional batch maceration at 50 °C. The obtained results demonstrate the high potential of UAEM to produce high-quality juice by controlling pectin degradation while reducing process temperature and equally highlight the matrix and enzyme specific effects of a simultaneous US treatment.     

Synergistic effect of ultrasonication and co-immobilized enzymes on tomato peels for lycopene extraction

In the present work, tomato peels were pre-treated using combination of ultrasound and enzyme co-immobilized amino-functionalized magnetic nanoparticles (AMNPs) for the efficient release of lycopene. To achieve maximum activity of enzymes in the co-immobilized form, optimization of several parameters were carried out. Moreover, the influence of ultrasound and enzyme co-immobilized magnetic nanoparticles on lycopene release was studied. Maximum lycopene release was obtained at 3% (w/w) enzyme co-immobilized AMNPs, pH 5.0, temperature of 50 °C, at 10 W ultrasound power and 20 min incubation time. After enzymatic pre-treatment, lycopene from the pre-treated mixture was extracted and separated using tri-solvent extraction method. Maximum recovery of lycopene using solvent extraction was obtained at 50 °C, 90 min of incubation time and agitation speed of 150 rpm. The presence of lycopene in the extract was confirmed by FT-IR, UV–vis spectroscopy and HPLC analysis. The co-immobilized bio-catalyst showed excellent reusability giving more than 50% lycopene yield even after 6th cycles of reuse.     

Ultrasound assisted enzymatic pre-treatment of high fat content dairy wastewater

This paper illustrates the application of ultrasound in a dairy waste water treatment for the removal of fat using enzyme as a catalyst. Lipase Z was used to perform the enzymatic pre-hydrolysis of a synthetic dairy wastewater containing around 2000 mg/L of fat content coupled with ultrasound irradiation. Different process parameters like effect of enzyme loading, temperature, ultrasound power, frequency, duty cycle and speed of agitation are optimized. The maximum hydrolysis of 78% is achieved at 0.2% enzyme loading (w/v), 30 °C temperature, 165 W of ultrasonication power at 25 kHz and 66% duty cycle. It was observed that the enzymatic pre-hydrolysis under the influence of ultrasound drastically reduces the reaction time from 24 h to 40 min as compared to conventional stirring with improved yield.     

串联酶解耦合超微粉碎法对蔗渣酶解的促进作用

报道了一种新颖的串联酶解(先酶I后酶II)耦合超微粉碎方法,并系统研究了其对蔗渣酶水解的促进作用. 通过对三种酶解方法(单酶I、单酶II、先酶I后酶II) 的比较发现,串联酶解对蔗渣酶解最为有效. 超微粉碎能破坏蔗渣细胞结构,使纤维素充分暴露出来便于酶解.在串联酶解耦合超微粉碎模式下,蔗渣在反应温度50 oC,pH=4.8,酶I(7.5 FPU/g底物)和酶II(5.0 FPU/g底物),摇床速率1200 r/min条件下反应72 h后,酶水解能得到65%的还原糖浓度,其中葡萄糖选择性为90.1%.     

Effects of ultrasound assisted cell wall disruption on physicochemical properties of camellia bee pollen protein isolates

Camellia bee pollen protein isolates were extracted by cell wall disruption using ultrasonication, freeze-thawing, enzymatic hydrolysis, and their combinations. The effects of these methods on microstructure of cell wall, protein release, protein yield, physiochemical properties and structure of proteins were investigated. As compared with physical treatments (ultrasonication, freeze-thawing and their combination), the enzymatic hydrolysis significantly improved the yield of proteins, because it not only promoted the release of proteins from the inside of pollen, but also released proteins in pollen wall. The proteins extracted by enzymatic hydrolysis method also exhibited better solubility, emulsifying and gelation properties due to the partial hydrolysis of proteins by protease. In addition, when ultrasound was combined with freeze-thawing or enzymatic hydrolysis, it could further improve the yield of proteins and the functional properties of proteins, which was mainly related to the changes of protein structure induced by cavitation effect of ultrasound.     

Effect of ultrasound,heating and enzymatic pre-treatment on bioactive compounds in juice from Berberis amurensis Rupr.

The aim of the study was to assess the influence of ultrasound (frequency 20 kHz, amplitude 70%, power 140 W for 10 min), heating (80 °C, 5 min) and enzymatic pre-treatment of mash (50 °C, Rohapect 10L at a dose of 0.23 g/1000 g, maceration time 60 min) on the yield, the content of phenolic compounds (including anthocyanins), ascorbic acid, and the antioxidative capacity of Berberis amurensis juice. Additionally, the polyphenols profile of this raw material and juices was identified. 25 phenolic compounds were identified in the fruit and 24 in juices. The content of phenolics in the fruit was 636 mg/100 g. Chlorogenic acid, 4-hydroxybenzoate and quercetin-3-O-glicoside were predominant. The content of anthocyanins in the fruit was 217 mg/100 g f.w., where peonidin-3-O-glucoside (98%) was predominant. The content of ascorbic acid amounted to 16.60 mg/100 g. The yield of the barberry juice pressing process ranged from 56% to 60% – there were no differences between the mash treatment methods. The enzymatic and thermal treatment of the mash resulted in the highest content of phenolic compounds in the juice. The sonication resulted in the highest content of anthocyanins, including peonidin-3-O-glucoside, as the main anthocyanin. The thermal treatment of the mash resulted in a lower loss of ascorbic acid than the other methods. The juice from the mash subjected to pectinolysis or heat treatment exhibited the highest antioxidative capacity.     

Impact of ultrasound on extractability of native collagen from tuna by-product and its ultrastructure and physicochemical attributes

The effect of ultrasound treatment (300 W; 0, 5, 10, 15, 20 and 25 min) on the extractability of acid soluble collagen from yellowfin tuna skin and its structural, physicochemical and functional properties were investigated. Ultrasound treatments significantly increased collagen extraction yield from the tuna skin up to 2.7 times, compared to the conventional extraction with acetic acid. The level of proline, hydroxyproline and thermal stability of collagens increased by applying ultrasound while their native triple-stranded helical structure was well-preserved, as revealed by X-ray diffraction and FTIR spectroscopy. However, ultrasound treatment reduced the particle size of the collagens which increased their pH and salt induced solubility. The water holding capacity and the emulsifying properties of ultrasound treated collagens were also higher than those produced with the conventional method. Altogether, the results suggested that ultrasonication can be a promising assistant technology for improving native collagen extraction efficiency from tuna skin and its functionality but its duration should be carefully optimized.     

Effects of microfiltration combined with ultrasonication on shelf life and bioactive protein of skim milk

To extend the shelf life and retain bioactive proteins in milk, this study utilized microfiltration (MF) combined with ultrasonication to treat skim milk and investigated its efficiency in removing bacteria and retaining bioactive proteins compared with HTST pasteurization and microfiltration alone. Results showed that microfiltration combined with ultrasonication at 1296 J/mL could completely remove the bacteria in skim milk. Ultrasonication further extended the shelf life (4 °C) of microfiltered skim milk, which could reach at least 40 days when MF was combined with ˃1296 J/mL ultrasonication. In addition, ELISA showed that HTST pasteurization significantly decreased the levels of IgG by ~30%, IgA by ~ 50%, IgM by ~60%, and lactoferrin by ~40%, whereas the activity of the enzymes lactoperoxidase and xanthine oxidase were also decreased by ~ 20%. Compared with HTST, MF alone or combined with ultrasonication retained these bioactive proteins to a larger degree. On the other hand, proteomics indicated both damage to casein micelle and fat globule structures in milk when ultrasonication at >1296 J/mL was applied, as shown by increases in caseins and milk fat globular proteins. Simultaneously, this ultrasound intensity also decreased levels of bioactive proteins, such as complement factors. Taken together, this study provided new insights that may help to implement this novel combination of non-thermal technologies for the dairy industry aimed at improving milk quality and functionality.     

Design consideration and modelling studies of ultrasound and ultraviolet combined approach for shelf-life enhancement of pine apple juice

Although both ultraviolet (UV) radiation and ultrasound (US) treatment have their capabilities in microbial inactivation, applying any one method alone may require a high dose for complete inactivation, which may affect the sensory and nutritional properties of pineapple juice. Hence, this study was intended to analyse and optimise the effect of combined US and UV treatments on microbial inactivation without affecting the selected quality parameters of pineapple juice. US treatment (33 kHz) was done at three different time intervals, viz. 10 min, 20 min and 30 min., after which, juice samples were subjected to UV treatment for 10 min at three UV dosage levels, viz. 1 J/cm², 1.3 J/cm², and 1.6 J/cm². The samples were evaluated for total colour difference, pH, total soluble solids (TSS), titrable acidity (TA), and ascorbic acid content; total bacterial count and total yeast count; and the standardization of process parameters was done using Response Surface Methodology and Artificial Neural Network. The results showed that the individual, as well as combined treatments, did not significantly impact the physicochemical properties while retaining the quality characteristics. It was observed that combined treatment resulted in 5 log cycle reduction in bacterial and yeast populations while the individual treatment failed. From the optimization studies, it was found that combined US and UV treatments with 22.95 min and1.577 J/cm² ensured a microbiologically safe product while retaining organoleptic quality close to that of fresh juice.     

Evaluation of ultrasound based sterilization approaches in terms of shelf life and quality parameters of fruit and vegetable juices

The present work evaluates the performance of ultrasound based sterilization approaches for processing of different fruit and vegetable juices in terms of microbial growth and changes in the quality parameters during the storage. Comparison with the conventional thermal processing has also been presented. A novel approach based on combination of ultrasound with ultraviolet irradiation and crude extract of essential oil from orange peels has been used for the first time. Identification of the microbial growth (total bacteria and yeast content) in the juices during the subsequent storage and assessing the safety for human consumption along with the changes in the quality parameters (Brix, titratable acidity, pH, ORP, salt, conductivity, TSS and TDS) has been investigated in details. The optimized ultrasound parameters for juice sterilization were established as ultrasound power of 100 W and treatment time of 15 min for the constant frequency operation (20 kHz). It has been established that more than 5 log reduction was achieved using the novel combined approaches based on ultrasound. The treated juices using different approaches based on ultrasound also showed lower microbial growth and improved quality characteristics as compared to the thermally processed juice. Scale up studies were also performed using spinach juice as the test sample with processing at 5 L volume for the first time. The ultrasound treated juice satisfied the microbiological and physiochemical safety limits in refrigerated storage conditions for 20 days for the large scale processing. Overall the present work conclusively established the usefulness of combined treatment approaches based on ultrasound for maintaining the microbiological safety of beverages with enhanced shelf life and excellent quality parameters as compared to the untreated and thermally processed juices.     

Ultrasound assisted enzymatic depolymerization of aqueous guar gum solution

The present work investigates the effectiveness of application of low intensity ultrasonic irradiation for the intensification of enzymatic depolymerization of aqueous guar gum solution. The extent of depolymerization of guar gum has been analyzed in terms of intrinsic viscosity reduction. The effect of ultrasonic irradiation on the kinetic and thermodynamic parameters related to the enzyme activity as well as the intrinsic viscosity reduction of guar gum using enzymatic approach has been evaluated. The kinetic rate constant has been found to increase with an increase in the temperature and cellulase loading. It has been observed that application of ultrasound not only enhances the extent of depolymerization but also reduces the time of depolymerization as compared to conventional enzymatic degradation technique. In the presence of cellulase enzyme, the maximum extent of depolymerization of guar gum has been observed at 60 W of ultrasonic rated power and ultrasonic treatment time of 30 min. The effect of ultrasound on the kinetic and thermodynamic parameters as well as the molecular structure of cellulase enzyme was evaluated with the help of the chemical reaction kinetics model and fluorescence spectroscopy. Application of ultrasound resulted in a reduction in the thermodynamic parameters of activation energy (E_a), enthalpy (ΔH), entropy (ΔS) and free energy (ΔG) by 47%, 50%, 65% and 1.97%, respectively. The changes in the chemical structure of guar gum treated using ultrasound assisted enzymatic approach in comparison to the native guar gum were also characterized by FTIR. The results revealed that enzymatic depolymerization of guar gum resulted in a polysaccharide with low degree of polymerization, viscosity and consistency index without any change in the core chemical structure which could make it useful for incorporation in food products.     

Using ultrasound technology for the inactivation and thermal sensitization of peroxidase in green coconut water

Green coconut water has unique nutritional and sensorial qualities. Despite the different technologies already studied, its enzymatic stability is still challenging. This study evaluated the use of ultrasound technology (US) for inactivating/sensitizing coconut water peroxidase (POD). The effect of both US application alone and as a pre-treatment to thermal processing was evaluated. The enzyme activity during US processing was reduced 27% after 30 min (286 W/L, 20 kHz), demonstrating its high resistance. The thermal inactivation was described by the Weibull model under non-isothermal conditions. The enzyme became sensitized to heat after US pre-treatment. Further, the use of US resulted in more uniform heat resistance. The results suggest that US is a good technology for sensitizing enzymes before thermal processing (even for an enzyme with high thermal resistance). Therefore, the use of this technology could decrease the undesirable effects of long times and/or the high temperatures of the conventional thermal processing.     

Study of cell killing effect on S180 by ultrasound activating protoporphyrin IX

The present study was initiated to investigate the potential biological mechanism of cell killing effect on isolate sarcoma 180 (S180) cells induced by ultrasound activating protoporphyrin IX (PPIX). S180 cells were exposed to ultrasound for 30 s duration, at a frequency of 2.2 MHz and an acoustic power of 3 W/cm² in the presence of 120 μM PPIX. The viability of cells was evaluated using trypan blue staining. The generation of oxygen free radicals in cell suspensions was detected immediately after treatment using a reactive oxygen detection kit. A copper reagent colorimetry method was used to measure the level of FFAs released into cell suspensions by the process of cell damage induced by ultrasound and PPIX treatment. Oxidative stress was assessed by measuring the activities of key antioxidant enzymes (i.e., SOD, CAT, GSH-PX) in S180 tumor cells. Treatment with ultrasound and PPIX together increased the cell damage rate to 50.91%, while treatment with ultrasound alone gave a cell damage rate to 24.24%, and PPIX alone kept this rate unchanged. Colorimetry and enzymatic chemical methods showed that the level of FFAs in cell suspension increased significantly after the treatment, while the activity of all the above enzymes decreased in tumor cells at different levels, and were associated with the generation of oxygen free radicals in cell suspension after treatment. The results indicate that oxygen free radicals may play an important role in improving the membrane lipid peroxidation, degrading membrane phospholipids to release FFAs, and decreasing the activities of the key antioxidant enzymes in cells. This biological mechanism might be involved in mediating the effects on S180 cells and resulting in the cell damage seen with SDT.     

Ultrasound assisted enzymatic degumming of crude soybean oil

The present work deals with ultrasound assisted enzymatic degumming (UAED) of crude soybean oil quantifying the extent of degumming (EOD), cavitational yield and synergistic index (f) for the combination approaches. The effect of different operating parameters such as enzyme loading, pH, presence of water, temperature and ultrasonic power on the EOD has been investigated. Ultrasound combined with enzyme at loading of 2.0 ml/L resulted in EOD as 92.2% under ambient conditions. Addition of water (5%) in combination with ultrasound and enzyme at 2.0 ml/L loading and pH of 5 resulted in maximum EOD (98.4%) in 120 min of treatment. The extent of phospholipid separation was also observed to be dependent on the power dissipation and maximum phospholipids separation was obtained at 100 W. Scale-up studies were performed at 500 ml and 1 L operating volume under optimized conditions of 2.0 ml/L as the enzyme loading, pH of 5, 5% water addition and ultrasonic power of 100 W where 93.63% and 91.15% phospholipid separation respectively was obtained. The effects of ultrasonic treatment were also quantified in terms of the acid value reduction and oxidative stability for the processed oil. It was demonstrated that suitable reduction in acid value (final value less than 1) and oxidative stability (TOTOX less than 4) is effectively obtained using UAED. Overall the approach of UAED was established to show much higher efficacy for soybean oil processing as compared to only ultrasound or only enzymatic treatment.     

Ultrasound-assisted dextranase entrapment onto Ca-alginate gel beads

In this research work, dextranase has immobilized onto calcium alginate beads using a novel ultrasound method. The process of immobilization of the enzyme was carried out in a one-step ultrasound process. Effects of ultrasound conditions on loading efficiency and immobilization yield of the enzyme onto calcium alginate beads were investigated. Furthermore, the activity of the free and immobilized enzymes prepared with and without ultrasound treatment, as a function of pH, temperature, recyclability and enzyme kinetic parameters, was compared. The maximum loading efficiency and the immobilization yield were observed when the immobilized dextranase was prepared with an ultrasonic irradiation at 25 kHz, 40 W for 15 min, under which the loading efficiency and the immobilization yield increased by 27.21% and 18.77%, respectively, compared with the immobilized enzymes prepared without ultrasonic irradiation. On the other hand, immobilized enzyme prepared with ultrasonic irradiation showed V_max and K_M value higher than that for the immobilized enzyme prepared without ultrasonic irradiation, likewise, both the catalytic and specificity constants of immobilized enzyme prepared with ultrasonic irradiation were higher than that for immobilized enzyme prepared without ultrasound, indicating that, this new ultrasonic method improved the catalytic kinetics activity of immobilized dextranase at all the reaction conditions studied. Compared with immobilized enzyme prepared without ultrasound treatment, the immobilized enzymes prepared with ultrasound irradiation exhibited: a higher pH optimum, optimal reaction temperature, activation energy, and thermal stability, as well as, a higher recyclability, which, illustrating the effectiveness of the sonochemical method. To the best of our knowledge, this is the first report on the effect of ultrasound treatments on the immobilization of dextranase.