Ultra-turrax Homogenization Research Articles

Combining Ultra-Turrax and ultrasonic homogenization to achieve higher vitamin E encapsulation efficiency in spray drying

Vitamin E, a soluble antioxidant widely used in the food and pharmaceutical industries, is rich in tocopherols and phytosterols. Since vitamin E molecules are highly sensitive to oxidation, encapsulation is a viable and effective technique for preservation of the properties of Vitamin E and improving its stability during storage, maintaining the nutritional value. In this work, the aim was to encapsulate concentrated vitamin E using a combination of Ultra-Turrax and ultrasonication to achieve higher encapsulation efficiency in spray drying. In the first stage, the vitamin E oil was encapsulated employing only Ultra-Turrax homogenization, with subsequent optimization of spray drying. The coating materials used were maltodextrin and whey protein isolate. Optimization of the spray drying step evaluated the effects of the drying air temperature (T) and the feed flow rate (Q), to obtain better yields and a high-quality product. In the second stage, the use of ultrasonication in an additional homogenization step was evaluated, aiming to further improve the encapsulation process. The results showed that the best drying conditions (first stage) were T = 180 °C and Q = 0.6 L/h, which provided the highest yield (67.73%) and high encapsulation efficiency (73.73%). The microspheres produced had similar properties, with mean diameters ranging from 0.64 to 12.99 μm. In the second stage of the investigation, the application of ultrasonication immediately after the Ultra-Turrax homogenization enabled the encapsulation efficiency to be increased to 94.05%, with a yield of 57.54%, using an ultrasonication time of only 7 min. This showed that addition of the ultrasonic homogenization step to the process greatly improved the encapsulation efficiency and could be used to produce vitamin E-enriched powder microcapsules by spray drying, with application in the food industry.

Unraveling the emulsifying activity of bio-based ionic liquids in the formation and stabilization of oil-in-water emulsions

Bio-based ionic liquids (ILs), especially those derived from fatty acids (FAs) have been considered promising compounds for the agri-food and bioproduct industries, due to their sustainable appeal, possibly low or non-toxic effect and the nutritional value of FAs. However, studies have been mainly focused on the use of ILs as greener solvents. This work investigated the application of ILs derived from FAs and diethanolamine as emulsifiers to form and stabilize oil-in-water emulsions using ultraturrax (PM) and high-pressure homogenization (H). The influence of the IL type obtained from different FAs (stearic or oleic acids), and vegetable oil type (sunflower or olive oil) and concentration (30:70 or 70:30, oil:water phase ratio) on the formation and stabilization of emulsions was evaluated. This study was focused on the zeta potential of IL aqueous solutions in different pH conditions, interfacial tension between vegetable oils and IL aqueous solutions at different concentrations, kinetic stability, droplet size and size distribution, optical microscopy, viscosity profile and rheological behavior of the emulsions. ILs presented highly negative ZP charge (−12.97–−74.81), high emulsifying ability at low concentrations (1 %) and led to emulsions with high kinetic stability (>30 days). The electrostatic stabilization mechanism may predominate over the steric in IL-based emulsions. The stabilization of emulsions with ILs was associated to lower oil droplet size (D3,2 = 0.60–4.09 µm, D4,3 = 0.95–9.91 μm) and emulsion viscosity (4.8 mPa·s-1.13 Pa·s), which were related to the IL molecular structure, oil type and concentration, and process. Emulsions prepared with stearic-based IL and sunflower oil by PM+H presented higher kinetic stability. The proposed ILs are presented as highly effective emulsifiers with potential application in the agri-food, pharmaceutical and cosmetic industries.

An integrated approach of homogenization-ultrasound-assisted extraction followed by high-speed countercurrent chromatography for rapidly preparative separation naphthoquinones and diarylheptanes from Juglands mandshurica Maxim. exocarp.

This research investigated the effectiveness of an integrated method for the extraction and separation of naphthoquinones and diarylheptanes from exocarp of Juglands mandshurica Maxim. (namely, green walnut husks). The target compounds were obtained by ultra-turrax homogenization (UTH) coupled with ultrasound-assisted extraction (UAE) technology followed by high-speed countercurrent chromatography (HSCCC). The UTH-UAE extraction method achieved higher efficiency with 2.49- and 2.36-fold to those by UAE, and 1.39- and 1.34-fold to those by UTH in a short time. HSCCC was adopted for further separation and purification; six target compounds, namely, regiolone (RE), juglone (JU), myricatomento-genin (MG), galleon (GA), 2-oxatrycyclo[13.2.2.13,7]eicosa-3,5,7(20),15,17,18-hexaen-10-16-diol (OE), and juglanin A (JA), were separated with more than 95.37% purities and more than 84.71% final recovery rates, respectively. In this study, the integrated strategy of extraction and separation could get high purity compounds quickly, which would provide time and solvent saved method for the natural products separation from plants.

Wood Hemicelluloses as Innovative Wall Materials for Spray-Dried Microencapsulation of Berry Juice: Part 1—Effect of Homogenization Techniques on their Feed Solution Properties

The use of wood hemicelluloses, including galactoglucomannans (GGM) and glucuronoxylans (GX), in spray-dried microencapsulation of bioactive compounds has not been reported. Our study aims to investigate the benefits of spray-dried GGM and GX powders (sGGM and sGX) along with the effects of homogenization techniques (magnetic stirring, ultrasonication, and a combination of UltraTurrax homogenization and microfluidization) on the physicochemical properties of feed solutions (10–20%, w/w). Feed solutions of bilberry juice with sGGM, sGX, and mixtures of either sGGM or sGX with methylcellulose (MC) or carboxymethylcellulose (CMC) were examined to produce highly stable feed solutions for spray-dried microencapsulation. The effects of ultrasonication amplitudes (30–80%) on the viscosity and particle size distribution of sGGM feed solutions were more profound than observed in their sGX counterparts. Unlike sGX feed solutions, sGGM feed solutions homogenized by ultrasonication and microfluidization formed a gel-like structure. Microfluidization also caused a loss of total anthocyanin content (TAC) of the feed solutions. Magnetic stirring resulted in no gel formation and in the lowest viscosity of the feed solutions; hence, it is an effective method for preparing hemicellulose feed solutions. sGGM and sGX powders have high heat stability with melting temperatures of 170–180 °C. The sGGM + CMC combination was more stable over 1 week of storage than the sGGM and sGX feed solutions. Storing the feed solutions reduced TAC and increased sGGM viscosity. Our results indicated that GGM and GX have high potential for use as wall materials in the spray-dried microencapsulation of bioactive compounds.

Comparison of methods to homogenize ricotta cheese samples for total solids determination

Ricotta cheese is an Italian dairy product obtained by heat-coagulation of the proteins in whey, resulting from cheese production. The homogenization method applied to collect ricotta cheese samples could affect the total solids (TS) contents of the products. The aim of this study was to determine the effects of 5 different homogenization methods of the samples collection applied for the accuracy in TS determination in ricotta cheese, including un-homogenized method (UNH), un-homogenized combined with the Ultra-Turrax (IKA-Werke GmbH & Co. KG) method (UNH-UTX), spoon-homogenized method (SPN), spoon-homogenized combined with Ultra-Turrax method (SPN-UTX), and Ultra-Turrax homogenized method (UTX). The repeatability and the standard deviation of repeatability are indicators of agreement between repeated measures for TS contents. Results reported that UNH ricotta cheese samples showed large variation in TS content with values ranging from 18.31% to 25.85% and a standard deviation of repeatability higher than 1%; SPN samples showed repeatability values higher than 0.35% and standard deviation of repeatability ranged until 1.36%, suggesting large variability even in this case; the Ultra-Turrax homogenization reported repeatability values lower than 0.1% and standard deviation of repeatability lower than 0.05%, indicating that this method provides repeatable measurements that may reduce the sources of uncertainty in TS determination.

Nanostructured polyelectrolyte complexes based on chitosan and sodium alginate containing rifampicin for the potential treatment of tuberculosis

Nanostructured polyelectrolyte complexes (nano PECs) were obtained by polyelectrolyte complexation technique from chitosan (CS) and sodium alginate (SA). Different polymer proportions were tested, as well as the addition order and homogenization type, to assess the influence on the nano PECs characteristics. The spherical shape and nanometric scale of the systems were observed by scanning electron microscopy (SEM). Nano PECs size, PDI, and zeta potential (ZP) ranged from 252 to 616 nm, from 0.22 to 0.73 and −50 to 30 mV, respectively. The increase of polymer proportion and the ultra-turrax homogenization led to the enlargement of particles size and PDI. However, no influence was observed on the ZP. The NP1s-Rb and NP4s-Rb, obtained through the sonicator with rifampicin (RIF) added before the CS and SA complexation, were selected due to the most promising characteristics of diameter (301 and 402 nm), PDI (0.27 and 0.26), and RIF incorporation (78 and 69%). The release profiles of RIF incorporated in both nano PECs were similar, with a sustained release of the drug for 180 min in phosphate buffer pH 7.2. The Weibull and the Korsmeyer–Peppas models better describe the RIF release from NP1s-Rb and NP4s-Rb, respectively, demonstrating that the release process was driven by different mechanism according to the particle composition. The nano PECs were lyophilized to prolong it stability and for possible nebulization. The addition of dextrose to the system allowed for resuspension after lyophilization. Therefore, with the results obtained, the incorporation of RIF in nano PECs based on CS and SA presents a promising system for the treatment of tuberculosis.

Stability of low-fat oil in water emulsions obtained by ultra turrax, rotor-stator and ultrasound homogenization methods

The stabilities of 20 formulations of low-fat oil in water emulsions were evaluated with Ultra Turrax, rotor-stator and ultrasound applied as homogenization methods. Emulsions were formulated with extra virgin olive oil (15–20% w/w), egg yolk (0–5% w/w), mustard (0–5% w/w) and vinegar (10–25% w/w). The stability was determined at 7 days of storage through the parameters: ζ potential (mV), droplet size (nm), phase separation (cm), and viscosity (µ). The most stable emulsions were found with less phase separation distance in order ultrasound, rotor-stator and Ultra Turrax. Emulsions with smaller droplet sizes were obtained with ultrasound. The highest viscosity was found in emulsions obtained with the rotor-stator homogenizer. Regarding sensory preference, 43% acceptance was obtained with the rotor-stator method versus 21% for ultrasound. To cooks and chefs the use of rotor stator as homogenization technology could be an opportunity to prepare low fat emulsions with lower separation phases without effects on overall taste perception.

New insights about flocculation process in sodium caseinate-stabilized emulsions

Flocculation process was studied in emulsions formulated with 10wt.% sunflower oil, 2, 5 or 7.5wt.% NaCas, and with or without addition of sucrose (0, 5, 10, 15, 20 or 30wt.%). Two different processing conditions were used to prepare emulsions: ultraturrax homogenization or further homogenization by ultrasound. Emulsions with droplets with diameters above (coarse) or below (fine) 1μm were obtained. Emulsions were analyzed for droplet size distribution by static light scattering (SLS), stability by Turbiscan, and structure by confocal laser scanning microscopy (CLSM) and small angle X-ray scattering (SAXS). SAXS data were fitted by a theoretical model that considered a system composed of poly dispersed spheres with repulsive interaction and presence of aggregates. Flocculation behavior was caused by the self-assembly properties of NaCas, but the process was more closely related to interfacial protein content than micelles concentration in the aqueous phase. The results indicated that casein aggregation was strongly affected by disaccharide addition, hydrophobic interaction of the emulsion droplets, and interactions among interfacial protein molecules. The structural changes detected in the protein micelles in different environments allowed understanding the macroscopic physical behavior observed in concentrated NaCas emulsions.

A simple multi-residue method for the determination of pesticides in fruits and vegetables using a methanolic extraction and ultra-high-performance liquid chromatography-tandem mass spectrometry: Optimization and extension of scope

In 2004, a new multi-residue pesticides method had been published using methanol as extraction solvent. Our goal for this study was to optimize the analytical scheme while extending the compound scope from 19 to 200 pesticides. The main changes from the original method take place at the sample extraction and processing with a special attention to make the overall method fit for routine analysis with minimal cost. Hence, after a quick Ultra-Turrax homogenization with a methanolic solution, the sample is simply diluted before the separation and detection by ultra-high-performance liquid chromatography and MS/MS detection for quantitative and confirmatory purposes. The performance of the method including limits of quantification (LOQs), linearity, matrix effect, precision was evaluated during validation in accordance with the European Union SANCO/12571/2013 regulatory guidelines. Two representative matrices, lettuce and orange, were selected and fortified at two concentration levels for these experiments. At the LOQ and ten times the LOQ, recoveries of the analytes were mostly within 70–120%, with coefficients of variation lower than 25% in intra-day repeatability conditions. In addition to being simple and fast, these results demonstrate the suitability of the optimized method for the analysis of large scope pesticides in routine laboratories.

Encapsulation of eugenol rich clove extract in solid lipid carriers

Clove (Syzygium aromaticum) is one of the richest sources of natural phenols. In this study, lipid formulations containing clove extract were spray dried to encapsulate the volatile and poor water soluble compounds, eugenol and eugenyl acetate, aiming to obtain solid redispersible powders. Five formulations were prepared to test two different solid lipids, two surfactants, and three drying carriers. The dried product was characterized by the eugenol and eugenyl acetate retention, in vitro antioxidant activity, and by relevant physical properties. The formulation containing glyceryl behenate, Poloxamer 188, and Maltodextrin DE10 presented better retention of bioactive compounds and good antioxidant activity. Therefore, this formulation was selected to study the influence of the dispersion method (high-shear mixing ultraTurrax, ultrasonication and high-pressure homogenization) and the drying technique (spray- and freeze-drying). The freeze-dried samples presented significantly higher retention of eugenol and eugenyl acetate than the spray-dried ones.

INNOVATIVE GROWTH IN DEVELOPING NEW METHODS FOR FORMULATING SOLID LIPID NANOPARTICLES AND MICROPARTICLES

The solid lipid nanopaticles are the colloidal drug delivery system which is spherical in shape and present in 10-1000nm particle sized range. The surfactant is used to stabilize the solid lipid nanoparticles to avoid aggregation. The Co-surfactant was used in addition to increase the micelles concentration. The optimization of surfactant concentration was used to stabilize the nanoparticles and microparticles formed and to decrease the particle size by decrease the aggregation. The manufacturing methods of the SLN are of four types, the high pressure homogenization which is further divides into two types hot homogenization method and cold homogenization method, Solvent-Diffusion evaporation method, ultrasonication method, and membrane contactor method. The non-uniform particles sizes were obtained from high pressure and ultra-sonication methods but the solvent-Diffusion Evaporation method and membrane contactor methods give uniform sized particles. But disadvantages of the later methods are the toxicity of organic solvent if not evaporates completely from the SLNs and the high cost of membrane contactor instrument is there in the formulation of SLNs. While the ultra-turrax and high pressure homogenization methods are the safest methods to use as compared to Solvent-Diffusion Evaporation method. The unpublished results have indicated that the drug release from the HPH and ultra-sonication gave highest drug release as compared to marketed conventional gel and formulation obtained by Solvent-Diffusion Evaporation method. Keywords: SLN, high pressure homogenization method, Solvent-Diffusion Evaporation method, ultrasonication method, Membrane contactor method

<I>In Vivo</I> Evaluation of Curcumin Loaded Nanosuspensions by Oral Administration

The current study was aimed at preparing the curcumin nanosuspension (CUR-NS) to improve the solubility and oral absorption of CUR. Prepared from a tandem of ultra-turrax homogenization and high pressure homogenization, the CUR-NS showed spherical shape under transmission electron microscopy with an average diameter of 210.2 nm. The absorption of CUR-NS in the gastrointestinal (GI) tract was studied in rats using an in situ single pass perfusion method. It was found that the absorption percentage in stomach was 9.20% within 2 h. The absorption process in intestine was first-process with passive diffusion mechanism, and the main absorptive segments were proven to be in the duodenum and jejunum. A pharmacokinetic study was conducted in mice after oral administration of CUR at 250 mg/kg in the form of either CUR-NS or CUR suspension. The plasma concentration-time curves were both fitted to a one-compartment model and the relative bioavailability of CUR-NS to CUR suspension was 680.03%. The effects of CUR-NS on the structural properties of the intestinal mucosal membrane of rats were investigated by fluorescence polarization and circular dichroism in vitro. After treatment with CUR-NS, not only the fluidity of intestinal mucosal membrane increased but also the conformation of the membrane protein loosed, which increased the gastrointestinal absorption of CUR-NS. These studies provided the evidence that NS was valuable as an oral delivery carrier to enhance the absorption of CUR.

Effect of glycation on sodium caseinate-stabilized emulsions obtained by ultrasound

This work explores the potential of high-intensity ultrasound to produce fine-dispersion, long-time-stable, oil-in-water emulsions prepared with native and glycated bovine sodium caseinate (SC). Regardless the ultrasound amplitude and time assayed, the sonicated emulsions of native SC at 0.5 mg/mL had much higher emulsifying activity indexes compared with those emulsions formed by Ultra-Turrax (IKA Werke GmbH & Co., Staufen, Germany) homogenization. Nevertheless, the native SC emulsions were very unstable despite the optimization of parameters such as protein concentration, amplitude of ultrasound wave, and sonication time by using a Box-Behnken design. Early glycation of SC with either galactose, lactose, or 10 kDa dextran substantially improved both emulsifying activity and the stability, whereas at advanced stages of glycation, SC emulsions showed notably reduced emulsifying properties, likely because extensive glycation of SC promoted its polymerization mainly through covalent cross-linking, as was demonstrated by particle size measurements. The increase in particle diameter of glycoconjugates likely affected the diffusion of SC from bulk to the oil–water interface and slowed the reorientation process of the protein at the interface. These findings show that the combined effect of early-stage glycation of SC and high-intensity ultrasound as an emergent technique to form emulsions has the potential to provide improved emulsions that could be used in several food applications.

Spray-freeze-drying of nanosuspensions: the manufacture of insulin particles for needle-free ballistic powder delivery

The feasibility of preparing microparticles with high insulin loading suitable for needle-free ballistic drug delivery by spray-freeze-drying (SFD) was examined in this study. The aim was to manufacture dense, robust particles with a diameter of around 50 microm, a narrow size distribution and a high content of insulin. Atomization using ultrasound atomizers showed improved handling of small liquid quantities as well as narrower droplet size distributions over conventional two-fluid nozzle atomization. Insulin nanoparticles were produced by SFD from solutions with a low solid content (<10 mg ml(-1)) and subsequent ultra-turrax homogenization. To prepare particles for needle-free ballistic injection, the insulin nanoparticles were suspended in matrix formulations with a high excipient content (>300 mg ml(-1)) consisting of trehalose, mannitol, dextran (10 kDa) and dextran (150 kDa) (abbreviated to TMDD) in order to maximize particle robustness and density after SFD. With the increase in insulin content, the viscosity of the nanosuspensions increased. Liquid atomization was possible up to a maximum of 250 mg of nano-insulin suspended in a 1.0 g matrix. However, if a narrow size distribution with a good correlation between theoretical and measurable insulin content was desired, no more than 150 mg nano-insulin could be suspended per gram of matrix formulation. Particles were examined by laser light diffraction, scanning electron microscopy and tap density testing. Insulin stability was assessed using size exclusion chromatography (SEC), reverse phase chromatography and Fourier transform infrared (FTIR) spectroscopy. Densification of the particles could be achieved during primary drying if the product temperature (T(prod)) exceeded the glass transition temperature of the freeze concentrate (T(g)') of -29.4 degrees C for TMDD (3331) formulations. Particles showed a collapsed and wrinkled morphology owing to viscous flow of the freeze concentrate. With increasing insulin loading, the d (v, 0.5) of the SFD powders increased and particle size distributions got wider. Insulin showed a good stability during the particle formation process with a maximum decrease in insulin monomer of only 0.123 per cent after SFD. In accordance with the SEC data, FTIR analysis showed only a small increase in the intermolecular beta-sheet of 0.4 per cent after SFD. The good physical stability of the polydisperse particles made them suitable for ballistic injection into tissue-mimicking agar hydrogels, showing a mean penetration depth of 251.3 +/- 114.7 microm.

Bonding states of thallium and cadmium in thallium-treated and native rape

The bonding states of thallium and cadmium were studied by gel filtration in leaves of thallium-treated and native rape after Ultra Turrax homogenization in buffer and subsequent ultracentrifugation. The separated cytosols contained about 70% of the total thallium and 50% of the total cadmium. Determinations of metals were performed by electrothermal and flame atomic absorption spectroscopy. Thallium-treated plants contained about 23 mg Tl/kg referring to wet weight. Almost the whole of cytoplasmic thallium was found as uncomplexed ionic species. Moreover, no dimethylthallium compounds have been detected by means of secondary-ion mass spectrometry after extraction and analysis for Tl 3+ was negative. Conclusively, in contaminated rape the predominate portion of thallium exists as free Tl +-ions. In untreated reference plants, all recovered thallium was bound. Probably the cytosolic binding factor is a peptide with a molecular weight of 3,800 g/mol containing no sulphurous amino acids. The biosynthesis of these native thallium-complexing agents cannot be induced in rape by the application of thallium. In both plant groups, free ionic cadmium could not be detected. The cytoplasmic cadmium was distributed on high (30,000 g/mol) and low molecular weight species (4,400 g/mol) in portions of about 50% and 30%, respectively. In addition, thallium had no influence on the bonding states of cadmium in native rape.

Quantitative retrieval of bacterial spores from oils

Membrane filtration and emulsification by ultrasonic mixing or ultraturrax homogenization were evaluated for their efficacy to retrieve bacterial spores from edible oils. Membrane filtration of oils containing spores, with subsequent transfer of the membrane to culture media, allowed at most 18% recovery of the spores. Emulsification of the oils by ultrasonication or ultraturrax homogenization with surface active agents showed generally high spore retrieval.

Isolation and Quantification of Cadmium and Copper-Species in Lettuce Plants

Cadmium and copper-species from native lettuce plants were isolated and quantified after Ultra Turrax homogenization in buffer and subsequent ltracentrifugation and gel filtration of the cytosol. From the cytoplasma, a high molecular weight metal binding-protein (>75000g/mol) containing 55% of the cytoplasmic cadmium and 20% of the cytoplasmic copper and a low molecular weight metal binding-protein (3200g/mol) containing 45% of the cytoplasmic cadmium and 70% of the cytoplasmic copper were isolated. Beside these there were two more copper binding-proteins of about 57000 and 25000g/mol, containing only small percentage of copper. The solid fragments of the cell, containing 50% of the total cadmium and 20% of the total copper respectively were not further examined. A broad variation in the metal balance from plant to plant was observed.