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Sample records for freeze-dried soya phosphatidylcholine

  1. Interaction of sodium diclofenac with freeze-dried soya phosphatidylcholine and unilamellar liposomes Interação do diclofenaco com fosfatidilcolina de soja e lipossomas unilamelares liofilizados

    Directory of Open Access Journals (Sweden)

    Luciana Biagini Lopes

    2006-12-01

    Full Text Available Phospholipids are widely used as structural amphiphilic compounds in liposome formulations. In this study, we have analyzed the interaction the sodium diclofenac (SD with soya phosphaditylcholine (PC and soya phosphatidylcholine from lyophilized small unilamellar liposomes (SUV. The changes in the properties of the co-lyophilized drug/PC from SUV liposomes, lyophilized PC from SUV liposomes, and lyophilized soya phosphatidylcholine, were studied by Differential Scanning Calorimetry (DSC. The DSC data showed that the previous organization of phospholipids molecules to form liposome affects intensely the thermal behavior of PC when compared to non-lipossomal PC. SD modified the thermal properties of PC from liposomes. It was verified that SD affects intensely the located group peaks in the regions of 120-140 ºC and in the higher temperature region of 240-260 ºC. The results of this work demonstrated that the presence of the drug modified the DSC behavior for both liposomal and non-liposomal PC and that these modifications can be easily monitored by DSC analysis.Fosfolipídios são freqüentemente usados como compostos anfifílicos estruturais em formulações de lipossomas. Neste estudo foi analisada a interação do diclofenaco sódico (SD com a fosfatidilcolina de soja liofilizada e a fosfatidilcolina de soja (PC obtida de lipossomas unilamelares pequenos liofilizados (SUV. As modificações nas propriedades da mistura fármaco/PC co-liofilizados a partir de SUV pré-formados, lipossomas de PC vazios e PC liofilizada foram estudadas por Calorimetria Diferencial de Varredura (DSC. Os resultados de DSC mostraram que a organização prévia das moléculas PC para formar lipossomas interfere significativamente no perfil de DSC da PC, quando comparada ao perfil de DSC da PC não-lipossômica. Verificou-se que o SD afeta intensamente o grupo de picos situados nas regiões de 120-140ºC e na região de mais alta temperatura (240-260ºC. Os resultados

  2. Freeze drying method

    International Nuclear Information System (INIS)

    Coppa, N.V.; Stewart, P.; Renzi, E.

    1999-01-01

    The present invention provides methods and apparatus for freeze drying in which a solution, which can be a radioactive salt dissolved within an acid, is frozen into a solid on vertical plates provided within a freeze drying chamber. The solid is sublimated into vapor and condensed in a cold condenser positioned above the freeze drying chamber and connected thereto by a conduit. The vertical positioning of the cold condenser relative to the freeze dryer helps to help prevent substances such as radioactive materials separated from the solution from contaminating the cold condenser. Additionally, the system can be charged with an inert gas to produce a down rush of gas into the freeze drying chamber to also help prevent such substances from contaminating the cold condenser

  3. Enhancement of absorption and hepatoprotective potential through soya-phosphatidylcholine-andrographolide vesicular system.

    Science.gov (United States)

    Jain, Pushpendra Kumar; Khurana, Navneet; Pounikar, Yogesh; Gajbhiye, Asmita; Kharya, Murli Dhar

    2013-06-01

    Andrographis paniculata is a medicinal herb used extensively for various ailments and contains therapeutically active phytoconstituent, andrographolide (AN). Although hepatoprotective activity of AN is established, but their bioavailability is restricted due to its rapid clearance. The aim of this study, therefore, was to formulate AN herbosomes (ANH) through complexation with naturally occurring soya-phosphatidylcholine (SPC), in order to enhance absorption. Prepared andrographolide-soy phosphatidylcholine (AN-SPC) complex prepared was subjected for characterisation of complex and formation of vesicular system known as ANH using rotary evaporation techniques. This complex was subjected to in vitro study using everted small intestine sac technique which showed significantly increased absorption of AN from the ANH as compared to the plain AN. The hepatoprotective potential of ANH and plain AN was evaluated using carbon tetrachloride inducing hepatotoxicity rat model and compared, in which ANH equivalent to 50 mg/kg of plain AN significantly restore serum glutamate oxalacetate transaminase (112.4 ± 9.67 for AN whereas 90.2 ± 4.23 for ANH) and serum glutamate pyruvate transaminase (109.3 ± 7.89 for AN whereas 90.6 ± 4.34 for ANH) level as compared to control group. The ANH showed significantly better absorption than plain AN and this effect of ANH was also comparable to the standard drug (Silymarin). The findings of present study reveal that ANH has better bioavailability as shown by in vitro absorption study and hence improved hepatoprotection as compared to plain AN at equivalent dose.

  4. Fundamentals of freeze-drying.

    Science.gov (United States)

    Nail, Steven L; Jiang, Shan; Chongprasert, Suchart; Knopp, Shawn A

    2002-01-01

    Given the increasing importance of reducing development time for new pharmaceutical products, formulation and process development scientists must continually look for ways to "work smarter, not harder." Within the product development arena, this means reducing the amount of trial and error empiricism in arriving at a formulation and identification of processing conditions which will result in a quality final dosage form. Characterization of the freezing behavior of the intended formulation is necessary for developing processing conditions which will result in the shortest drying time while maintaining all critical quality attributes of the freeze-dried product. Analysis of frozen systems was discussed in detail, particularly with respect to the glass transition as the physical event underlying collapse during freeze-drying, eutectic mixture formation, and crystallization events upon warming of frozen systems. Experiments to determine how freezing and freeze-drying behavior is affected by changes in the composition of the formulation are often useful in establishing the "robustness" of a formulation. It is not uncommon for seemingly subtle changes in composition of the formulation, such as a change in formulation pH, buffer salt, drug concentration, or an additional excipient, to result in striking differences in freezing and freeze-drying behavior. With regard to selecting a formulation, it is wise to keep the formulation as simple as possible. If a buffer is needed, a minimum concentration should be used. The same principle applies to added salts: If used at all, the concentration should be kept to a minimum. For many proteins a combination of an amorphous excipient, such as a disaccharide, and a crystallizing excipient, such as glycine, will result in a suitable combination of chemical stability and physical stability of the freeze-dried solid. Concepts of heat and mass transfer are valuable in rational design of processing conditions. Heat transfer by conduction

  5. Impregnation of leather during "freeze-drying"

    DEFF Research Database (Denmark)

    Storch, Mikkel; Vestergaard Poulsen Sommer, Dorte; Hovmand, Ida

    2016-01-01

    Freeze-drying is a recognized method for the preservation of waterlogged objects. Naturally, freeze-drying has also been used for waterlogged archaeological leather often after treatment with Na2.EDTA and impregnation with PEG; but the treated leather sometimes suffers from “excessive drying......” becoming too stiff and brittle. The aim of this study was to examine the effect of a conventional freeze-drying method against an alternative freeze-drying method that preserves the natural moisture content of the leather. Both new and archaeological waterlogged leather were included in the study...... suggest that the process which takes place within the leather during the freeze-drying in not actual freeze-drying, but rather a sophisticated way of distributing the impregnating agent. The pure ice phase freezes out, but the impregnating agent remains liquid as the temperature does not become low enough...

  6. Well-plate freeze-drying

    DEFF Research Database (Denmark)

    Trnka, Hjalte; Rantanen, Jukka; Grohganz, Holger

    2015-01-01

    Abstract Context: Freeze-drying in presence of excipients is a common practice to stabilize biomacromolecular formulations. The composition of this formulation is known to affect the quality of the final product. Objective: The aim of this study was to evaluate freeze-drying in well...... no significant edge effect was found for any of the quality attributes analyzed. Conclusion: Freeze-drying in well-plates was found to be a suitable and representative high throughput platform for formulation screening....

  7. Mechanisms of deterioration of nutrients. [of freeze dried foods

    Science.gov (United States)

    Karel, M.; Flink, J. M.

    1976-01-01

    Methods which produce freeze dried foods of improved quality were examined with emphasis on storage stability. Specific topics discussed include: microstructure of freeze dried systems, investigation of structural changes in freeze dried systems, artificial food matrices, osmotic preconcentration to yield improved quality freeze dried fruits, and storage stability of osmotically preconcentrated freeze dried fruits.

  8. Freeze-drying of lactic acid bacteria.

    Science.gov (United States)

    Fonseca, Fernanda; Cenard, Stéphanie; Passot, Stéphanie

    2015-01-01

    Lactic acid bacteria are of great importance for the food and biotechnology industry. They are widely used as starters for manufacturing food (e.g., yogurt, cheese, fermented meats, and vegetables) and probiotic products, as well as for green chemistry applications. Freeze-drying or lyophilization is a convenient method for preservation of bacteria. By reducing water activity to values below 0.2, it allows long-term storage and low-cost distribution at suprazero temperatures, while minimizing losses in viability and functionality. Stabilization of bacteria via freeze-drying starts with the addition of a protectant solution to the bacterial suspension. Freeze-drying includes three steps, namely, (1) freezing of the concentrated and protected cell suspension, (2) primary drying to remove ice by sublimation, and (3) secondary drying to remove unfrozen water by desorption. In this chapter we describe a method for freeze-drying of lactic acid bacteria at a pilot scale, thus allowing control of the process parameters for maximal survival and functionality recovery.

  9. Sysnthesis of powders by freeze-drying

    International Nuclear Information System (INIS)

    Johnson, S.M.; Gusman, M.I.; Hildenbrand, D.L.

    1988-01-01

    The freeze-drying method of synthesizing powders of the superconducting oxide YBa 2 Cu 3 O 7 - δ is described. This process produces homogeneous, submicron powders of high purity. The effects of salt selection, solution concentration and pH on the process are described. Some evaluation of the sintering behavior and the effects on critical current density are included

  10. Preservation of flavor in freeze dried green beans

    Science.gov (United States)

    Huber, C. S.; Heidelbaugh, N. D.; Davis, D.

    1973-01-01

    Before freeze drying, green beans are heated to point at which their cell structure is altered. Beans freeze dried with altered cell structure have improved rehydration properties and retain color, flavor, and texture.

  11. SOME STUDIES ON FREEZE - DRIED ARTERIES

    Directory of Open Access Journals (Sweden)

    H. Sadeghi - Nejad

    1970-01-01

    Full Text Available (1 The secondary stage of freeze - drying, particularly the last day, is not important and I suggest the whole procedure is reduced to three days, the primary stage occupying two of these. (2 The mothod used obtains the satisfactory low level of residual moisture. RESUME (3 Experiments on reconstitution with saline and distilled water show that distilled water is more satisfactory and I suggest that saline should not he used.

  12. Microwave Augmented Freeze-Drying - Four Studies

    Science.gov (United States)

    1994-04-01

    F.J. 1G76. Pigments in "Principles of Food Science". O.R. Fennema, ed., Marcel Dekkar, Inc., New York. Datta, A.K. and Hu, W. 1992. Optimization of...and Wilke, C.R 1967. The relationship between transport properties and rates of freeze-drying of poultry meat. AIChE J. 13:428. Slater, L.E. 1975

  13. Sperm Preservation using Freeze-Drying Method

    Directory of Open Access Journals (Sweden)

    TAKDIR SAILI

    2005-03-01

    Full Text Available Since the discovery of cryopreservation method for bull semen, cryopreservation become an alternative method for maintaining gamet resources of certain animal which is threatened or near extinction. This technology was then applied to the preservation of embryo, oocyte, ovary and testis. The application of intracytoplasmic sperm injection (ICSI for which sperm motility is unnecessary had supported the effort to create simplified method such as freeze-drying for sperm preservation. Due to the benefit of ICSI over the conventional in vitro fertilization (IVF the spermatozoon could be mechanically driven to pass through the zona pellucida and entering the cytoplasm of oocytes prior to fertilization. The freeze-drying method is an alternative method in sperm preservation which ignored the motility of sperm. The sperm resulted from this technique is in drying state, therefore, it might be stored in room temperature or in refrigerator. Many reports have claimed that freeze-dried sperm which is not motile but has an intact DNA was able to fertilize oocytes, even produced offspring in mouse.

  14. Atmospheric freeze drying assisted by power ultrasound

    International Nuclear Information System (INIS)

    Santacatalina, J V; Cárcel, J A; Garcia-Perez, J V; Mulet, A; Simal, S

    2012-01-01

    Atmospheric freeze drying (AFD) is considered an alternative to vacuum freeze drying to keep the quality of fresh product. AFD allows continuous drying reducing fix and operating costs, but presents, as main disadvantage, a long drying time required. The application of power ultrasound (US) can accelerate AFD process. The main objective of the present study was to evaluate the application of power ultrasound to improve atmospheric freeze drying of carrot. For that purpose, AFD experiments were carried out with carrot cubes (10 mm side) at constant air velocity (2 ms −1 ), temperature (−10°C) and relative humidity (10%) with (20.5 kWm −3 ,USAFD) and without (AFD) ultrasonic application. A diffusion model was used in order to quantify the influence of US in drying kinetics. To evaluate the quality of dry products, rehydration capacity and textural properties were determined. The US application during AFD of carrot involved the increase of drying rate. The effective moisture diffusivity identified in USAFD was 73% higher than in AFD experiments. On the other hand, the rehydration capacity was higher in USAFD than in AFD and the hardness of dried samples did not show significant (p<0.05) differences. Therefore, US application during AFD significantly (p<0.05) sped-up the drying process preserving the quality properties of the dry product.

  15. Physical Stability of Freeze-Dried Isomalt Diastereomer Mixtures

    DEFF Research Database (Denmark)

    Koskinen, Anna-Kaisa; Fraser-Miller, Sara J.; Bøtker, Johan P.

    2016-01-01

    Purpose Isomalt is a sugar alcohol used as an excipient in commercially available solid oral dosage forms. The potential of isomalt as a novel freeze-drying excipient was studied in order to increase knowledge of the behavior of isomalt when it is freeze-dried. Methods Isomalt was freeze-dried in......Purpose Isomalt is a sugar alcohol used as an excipient in commercially available solid oral dosage forms. The potential of isomalt as a novel freeze-drying excipient was studied in order to increase knowledge of the behavior of isomalt when it is freeze-dried. Methods Isomalt was freeze......-dried in four different diastereomer compositions and its physical stability was investigated with differential scanning calorimetry, Fourier-transform infrared and Raman spectroscopy, X-ray powder diffraction, Karl-Fischer titration and thermogravimetric analysis in order to verify the solid state form...

  16. Limonene encapsulation in freeze dried gellan systems.

    Science.gov (United States)

    Evageliou, Vasiliki; Saliari, Dimitra

    2017-05-15

    The encapsulation of limonene in freeze-dried gellan systems was investigated. Surface and encapsulated limonene content was determined by measurement of the absorbance at 252nm. Gellan matrices were both gels and solutions. For a standard gellan concentration (0.5wt%) gelation was induced by potassium or calcium chloride. Furthermore, gellan solutions of varying concentrations (0.25-1wt%) were also studied. Limonene was added at two different concentrations (1 and 2mL/100g sample). Gellan gels encapsulated greater amounts of limonene than solutions. Among all gellan gels, the KCl gels had the greater encapsulated limonene content. However, when the concentration of limonene was doubled in these KCl gels, the encapsulated limonene decreased. The surface limonene content was significant, especially for gellan solutions. The experimental conditions and not the mechanical properties of the matrices were the dominant factor in the interpretation of the observed results. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Accelerated storage testing of freeze-dried Pseudomonas ...

    African Journals Online (AJOL)

    The viability of freeze-dried P. fluorescens strains (BTP1, PI9 and BB2) was evaluated by using the Arrhenius model. This model was described by measuring the reaction rate constants (D or k) and temperature sensitivity of rate constant (z or Ea). The freeze-dried P. fluorescens strains were stored in glass tubes at 60, ...

  18. Accelerated storage testing of freeze-dried Pseudomonas ...

    African Journals Online (AJOL)

    Erika-Chris

    storage and it would be useful to increase culture viability during storage. The viability of freeze-dried. P. fluorescens ... assessment of viable cells, while the residual water content is omitted (Hernandez et al., 2009). The ..... Effects of micronization on viability andthermotolerance of probiotic freeze-dried cultures. Int. Dairy J.

  19. Freeze-drying of live virus vaccines: A review.

    Science.gov (United States)

    Hansen, L J J; Daoussi, R; Vervaet, C; Remon, J-P; De Beer, T R M

    2015-10-13

    Freeze-drying is the preferred method for stabilizing live, attenuated virus vaccines. After decades of research on several aspects of the process like the stabilization and destabilization mechanisms of the live, attenuated viruses during freeze-drying, the optimal formulation components and process settings are still matter of research. The molecular complexity of live, attenuated viruses, the multiple destabilization pathways and the lack of analytical techniques allowing the measurement of physicochemical changes in the antigen's structure during and after freeze-drying mean that they form a particular lyophilization challenge. The purpose of this review is to overview the available information on the development of the freeze-drying process of live, attenuated virus vaccines, herewith focusing on the freezing and drying stresses the viruses can undergo during processing as well as on the mechanisms and strategies (formulation and process) that are used to stabilize them during freeze-drying. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Organic acid catalyzed carbon aerogels with freeze-drying

    Science.gov (United States)

    Xu, Yuelong; Yan, Meifang; Liu, Zhenfa

    2017-09-01

    Carbon aerogels (CAs) were synthesized via a sol-gel process by condensation-polymerization of phloroglucinol, resorcinol and formaldehyde using 2,4-dihydroxybenzoic acid as catalyst with freeze-drying. The effects of the freeze-drying method on the texture and pore structure were studied. Meanwhile the structure of carbon aerogels was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and a surface-area analyzer. The results show that the freeze-drying method and acid catalyst were good for the specific surface area of carbon aerogel, up to 765m2 g-1, and pore size distribution.

  1. SOME STUDIES ABOUT CEREALS BEHAVIOR DURING FREEZE DRYING PROCESS

    Directory of Open Access Journals (Sweden)

    GABRIELA-VICTORIA MNERIE

    2009-05-01

    Full Text Available The paper presents some special method and equipment and the principal advantages of freeze-dried food. The freeze drying is a good method of freeze-drying for make some experiments with many kind of cereals, for the improvement that in food production. It is necessary and is possible to study the corn oil extract, wheat flour, the maltodextrin from corn, modified cornstarch, spice extracts, soy sauce, hydrolyzed wheat gluten, partially hydrogenated soybean and cottonseed oil etc. That is very porous, since it occupies the same volume as the original and so rehydrates rapidly. There is less loss of flavour and texture than with most other methods of drying.

  2. Freeze-drying microscopy in mathematical modeling of a biomaterial freeze-drying

    Directory of Open Access Journals (Sweden)

    Camila Figueiredo Borgognoni

    2012-06-01

    Full Text Available Transplantation brings hope for many patients. A multidisciplinary approach on this field aims at creating biologically functional tissues to be used as implants and prostheses. The freeze-drying process allows the fundamental properties of these materials to be preserved, making future manipulation and storage easier. Optimizing a freeze-drying cycle is of great importance since it aims at reducing process costs while increasing product quality of this time-and-energy-consuming process. Mathematical modeling comes as a tool to help a better understanding of the process variables behavior and consequently it helps optimization studies. Freeze-drying microscopy is a technique usually applied to determine critical temperatures of liquid formulations. It has been used in this work to determine the sublimation rates of a biological tissue freeze-drying. The sublimation rates were measured from the speed of the moving interface between the dried and the frozen layer under 21.33, 42.66 and 63.99 Pa. The studied variables were used in a theoretical model to simulate various temperature profiles of the freeze-drying process. Good agreement between the experimental and the simulated results was found.A prática da transplantação traz esperança para muitos pacientes. Uma visão multidisciplinar nessa área visa à produção de tecidos biológicos para serem utilizados como implantes e próteses. A liofilização é um processo de secagem que preserva características essenciais desses materiais, facilitando sua manipulação e armazenamento. A liofilização é um processo que requer muito tempo e energia e sua otimização é muito importante, pois permite reduzir custos de processo melhorando a qualidade do produto. A modelagem matemática é uma ferramenta que permite descrever o comportamento do produto durante o processo e, consequentemente, auxilia os estudos de otimização. Microscopia óptica acoplada à liofilização, uma t

  3. Microwave Enhanced Freeze Drying of Solid Waste, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The development of advanced methods for Microwave Enhanced Freeze Drying of Solid Waste (MEFDSW) is proposed. Methods for the recovery of relatively pure water as a...

  4. Microwave Enhanced Freeze Drying of Solid Waste, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Development of technology for Microwave Enhanced Freeze Drying of Solid Waste (MEFDSW) is proposed. The present state of the art for solid waste stabilization using...

  5. Freeze-drying of silica nanoparticles: redispersibility toward nanomedicine applications.

    Science.gov (United States)

    Picco, Agustin S; Ferreira, Larissa F; Liberato, Michelle S; Mondo, Gabriela B; Cardoso, Mateus B

    2018-01-01

    To study freeze-drying of silica nanoparticles (SiO 2 NPs) in order to find suitable conditions to produce lyophilized powders with no aggregation after resuspension and storage. SiO 2 NPs were synthesized using a Stöber-based procedure, and characterized by scanning electron microscopy, dynamic light scattering and nitrogen adsorption/desorption isotherms. SiO 2 NPs hydrodynamic diameters were compared prior and after freeze-drying in the presence/absence of carbohydrate protectants. Glucose was found to be the most suitable protectant against the detrimental effects of lyophilization. The minimum concentration of carbohydrate required to effectively protect SiO 2 NPs from aggregation during freeze-drying is influenced by the nanoparticle's size and texture. Negligible aggregation was observed during storage. Carbohydrates can be used during SiO 2 NPs freeze-drying process to obtain redispersable solids that maintain original sizes without residual aggregation.

  6. Simulation Study on Freeze-drying Characteristics of Mashed Beef

    OpenAIRE

    Tambunan, Armansyah H; Solahudin, M; Rahajeng, Estri

    2000-01-01

    Drying characteristic of a particular product is important in analyzing the appropriateness of the drying method for the product. This is especially important for freeze drying, which is known as the most expensive drying method, asideji-om its good drying quality. The objectives of this experiment are to develop a computer simulation program using a retreating drying-frontmodel for predicting freeze drying characteristics of mashed nteat, especially for the influence of sublimation temperatu...

  7. Mechanisms of deterioration of nutrients. [improved quality of freeze-dried foods

    Science.gov (United States)

    Karel, M.; Flink, J. M.

    1978-01-01

    Methods for improving the quality of freeze-dried foods were investigated. Areas discussed include: (1) microstructure of freeze-dried systems, (2) structural changes in freeze-dried systems, (3) artificial food matrices, and (4) osmotic preconcentration to yield improved freeze-dried products.

  8. CFD modelling of condensers for freeze-drying processes

    Indian Academy of Sciences (India)

    ... the condenser, in order to evaluate condenser efficiency and gain deeper insights of the process to be used for the improvement of its design. Both a complete laboratory-scale freeze-drying apparatus and an industrial-scale condenser have been investigated in this work, modelling the process of water vapour deposition.

  9. CFD modelling of condensers for freeze-drying processes

    Indian Academy of Sciences (India)

    Both a complete laboratory-scale freeze-drying apparatus and an industrial-scale condenser have been investigated in this work, modelling the process of water vapour deposition. Different operating conditions have been consid- ered and the influence exerted by the inert gas as well as other parameters has been.

  10. Preparation of superconducting powders by freeze-drying

    International Nuclear Information System (INIS)

    Johnson, S.M.; Gusman, M.I.; Rowcliffe, D.J.; Geballe, T.H.; Sun, J.Z.

    1987-01-01

    A method of preparing superconducting powders by freeze-drying is described. Powders produced by this method are homogeneous, have high purities, and are very reactive. Materials sintered from these powders have densities up to 89% of the theoretical density, and exhibit very sharp resistivity drops and large Meissner effects. The microstructure of the materials is very sensitive to the sintering temperature

  11. Freeze-drying of filamentous fungi and yeasts

    NARCIS (Netherlands)

    Tan, C.S.

    2011-01-01

    The aim of this thesis was to optimize the freeze-drying protocol for fungi in general and for those genera that do not survive this preservation method, in particular. To this end, the influence of the cooling rate, the lyoprotectant and the drying process itself was examined. Since most fungi

  12. Apparatus for freeze drying of biologic and sediment samples

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    Freeze drying to obtain water from individual samples, though not complicated, usually requires considerable effort to maintain the cold traps on a 24-hr basis. In addition, the transfer of a sample from sample containers to freeze-dry flasks is usually made with some risk of contamination to the sample. If samples are large, 300 g to 600 g, usually several days are required to dry the samples. The use of an unattended system greatly improves personnel and drying efficiency. Commercial freeze dryers are not readily applicable to the problems of collecting water from individual samples, and lab-designed collectors required sample transfer and continual replenishment of the dry ice. A freeze-dry apparatus for collecting water from individual sediment and/or biological samples was constructed to determine the tritium concentrations in fish for dose calcaluations and the tritium distribution in sediment cores for water movement studies. The freeze, dry apparatus, which can handle eight samples simultaneously and conveniently, is set up for unattended 24-hr operation and is designed to avoid sample transfer problems

  13. Heat and Mass Transfer Model in Freeze-Dried Medium

    Science.gov (United States)

    Alfat, Sayahdin; Purqon, Acep

    2017-07-01

    There are big problems in agriculture sector every year. One of the major problems is abundance of agricultural product during the peak of harvest season that is not matched by an increase in demand of agricultural product by consumers, this causes a wasted agricultural products. Alternative way was food preservation by freeze dried method. This method was already using heat transfer through conduction and convection to reduce water quality in the food. The main objective of this research was to design a model heat and mass transfer in freeze-dried medium. We had two steps in this research, the first step was design of medium as the heat injection site and the second was simulate heat and mass transfer of the product. During simulation process, we use physical property of some agriculture product. The result will show how temperature and moisture distribution every second. The method of research use finite element method (FEM) and will be illustrated in three dimensional.

  14. Sintering of a freeze-dried 10 mol% Y2O3-stabilized zirconia

    International Nuclear Information System (INIS)

    Rakotoson, A.; Paulus, M.

    1983-01-01

    After presenting the results of freeze drying a sulfate solution, the authors describe a preparation process in which the freeze-drying technique by addition of a suspension of stabilized zirconia in the liquid solution before freeze-drying. This process breaks the polymeric chains, increases the green density of the compact, and decreases the sintering temperature. The mechanisms involved are discussed

  15. Freeze-drying wet digital prints: An option for salvage?

    International Nuclear Information System (INIS)

    Juergens, M C; Schempp, N

    2010-01-01

    On the occasion of the collapse of the Historical Archive of the City of Cologne in March 2009 and the ensuing salvage effort, questions were raised about the use of freeze-drying for soaked digital prints, a technique that has not yet been evaluated for these materials. This study examines the effects of immersion, air-drying, drying in a blotter stack, freezing and freeze-drying on 35 samples of major digital printing processes. The samples were examined visually before, during and after testing; evaluation of the results was qualitative. Results show that some prints were already damaged by immersion alone (e.g. bleeding inks and soluble coatings) to the extent that the subsequent choice of drying method made no significant difference any more. For those samples that did survive immersion, air-drying proved to be crucial for water-sensitive prints, since any contact with the wet surface caused serious damage. Less water-sensitive prints showed no damage throughout the entire procedure, regardless of drying method. Some prints on coated media suffered from minor surface disruption up to total delamination of the surface coating due to the formation of ice crystals during shock-freezing. With few exceptions, freeze-drying did not cause additional damage to any of the prints that hadn't already been damaged by freezing. It became clear that an understanding of the process and materials is important for choosing an appropriate drying method.

  16. Combined electrohydrodynamic (EHD) and vacuum freeze drying of shrimp

    International Nuclear Information System (INIS)

    Hu, Yucai; Huang, Qiang; Bai, Yaxiang

    2013-01-01

    To improve the drying qualities of shrimp, a combination of electrohydrodynamic (EHD) and vacuum freeze drying (FD) is examined. The drying rate, the shrinkage, the rehydration ratio, and the sensory properties including the color and trimness of the dried products under different drying methods (including combination drying of EHD and FD, EHD drying and FD drying) are measured. Compared with FD and EHD drying alone, the combined process consumes less drying time, and the product processed by combined drying displays lower shrinkage, higher rehydration rate and better sensory qualities.

  17. Electrochemical properties of carbon aerogels with freeze - drying

    Science.gov (United States)

    Xu, Yuelong; Yan, Meifang; Liua, Zhenfa

    2017-09-01

    Carbon aerogels (CAs) were prepared via a sol-gel process by polymerization of phloroglucinol, resorcinol and formaldehyde using 2,4-dihydroxybenzoic acid as catalyst with freeze-drying. The electrochemical properties were characterized using cyclic voltammetry, galvanostatic charge-discharge measurements and electrochemical impedance spectroscopy (EIS). The specific capacitance of corresponding CAs was up to 131 F g-1 and 105 F g-1 at the density of 0.5 A g-1 and 1.0 A g-1, respectively.

  18. Impact of the freeze-drying process on product appearance, residual moisture content, viability, and batch uniformity of freeze-dried bacterial cultures safeguarded at culture collections.

    Science.gov (United States)

    Peiren, Jindrich; Hellemans, Ann; De Vos, Paul

    2016-07-01

    In this study, causes of collapsed bacterial cultures in glass ampoules observed after freeze-drying were investigated as well as the influence of collapse on residual moisture content (RMC) and viability. Also, the effect of heat radiation and post freeze-drying treatments on the RMC was studied. Cake morphologies of 21 bacterial strains obtained after freeze-drying with one standard protocol could be classified visually into four major types: no collapse, porous, partial collapse, and collapse. The more pronounced the collapse, the higher residual moisture content of the freeze-dried product, ranging from 1.53 % for non-collapsed products to 3.62 % for collapsed products. The most important cause of collapse was the mass of the inserted cotton plug in the ampoule. Default cotton plugs with a mass between 21 and 30 mg inside the ampoule did not affect the viability of freeze-dried Aliivibrio fischeri LMG 4414(T) compared to ampoules without cotton plugs. Cotton plugs with a mass higher than 65 mg inside the ampoule induced a full collapsed product with rubbery look (melt-back) and decreasing viability during storage. Heat radiation effects in the freeze-drying chamber and post freeze-drying treatments such as exposure time to air after freeze-drying and manifold drying time prior to heat sealing of ampoules influenced the RMC of freeze-dried products. To produce uniform batches of freeze-dried bacterial strains with intact cake structures and highest viabilities, inserted cotton plugs should not exceed 21 mg per ampoule. Furthermore, heat radiation effects should be calculated in the design of the primary drying phase and manifold drying time before heat sealing should be determined as a function of exposure time to air.

  19. Successful long-term preservation of rat sperm by freeze-drying.

    Directory of Open Access Journals (Sweden)

    Takehito Kaneko

    Full Text Available BACKGROUND: Freeze-drying sperm has been developed as a new preservation method where liquid nitrogen is no longer necessary. An advantage of freeze-drying sperm is that it can be stored at 4 °C and transported at room temperature. Although the successful freeze-drying of sperm has been reported in a number of animals, the possibility of long-term preservation using this method has not yet been studied. METHODOLOGY/PRINCIPAL FINDINGS: Offspring were obtained from oocytes fertilized with rat epididymal sperm freeze-dried using a solution containing 10 mM Tris and 1 mM EDTA adjusted to pH 8.0. Tolerance of testicular sperm to freeze-drying was increased by pre-treatment with diamide. Offspring with normal fertility were obtained from oocytes fertilized with freeze-dried epididymal sperm stored at 4 °C for 5 years. CONCLUSIONS AND SIGNIFICANCE: Sperm with -SS- cross-linking in the thiol-disulfide of their protamine were highly tolerant to freeze-drying, and the fertility of freeze-dried sperm was maintained for 5 years without deterioration. This is the first report to demonstrate the successful freeze-drying of sperm using a new and simple method for long-term preservation.

  20. Freeze-drying behaviour of pasteurized whole egg

    International Nuclear Information System (INIS)

    Melike Sakin; Merve Samli; Gizem Kor, A.; Figen Kaymak-Ertekin

    2009-01-01

    Because it provides full nutritional and certain desirable functional attributes, egg products are widely used as ingredients in many food products. Dried egg is especially valuable for being stable, easily mixable and having a long shelf life. It is necessary to know the effects of drying conditions onto the moisture removal behaviour and the functional properties of the powder product, to serve the egg powder as an alternative. An experimental study was conducted to achieve an understanding of the freeze-drying behaviour of pasteurized whole egg having 24% dry solids. In order to determine the moisture removal behaviour; the percent moisture loss (w/w), the average moisture content and the drying rates were obtained, the drying curves were developed and total drying times were determined, also the movement of the dry-wet boundary between the frozen layer and the dry porous layer formed by sublimation of ice crystals were investigated during a complete process. The physical properties of pasteurized whole egg such as; colour, water activity (a w ), the morphological structure (through SEM analysis) and functional properties (foam stability and dissolubility) were determined. The net colour change (ΔE) was about 22, independent of layer thickness. The water activity decreased to 0.22 at the end of drying. The SEM images of freeze-dried and slightly milled egg powder samples at magnification levels of 500 and 1000 showed the porous structure caused by sublimation of ice crystals generated within the egg structure during air blast freezing. The dissolubility and foaming capacity of powder egg were observed to be lower compared to those of pasteurized liquid egg. (author)

  1. The effect of dryer load on freeze drying process design.

    Science.gov (United States)

    Patel, Sajal M; Jameel, Feroz; Pikal, Michael J

    2010-10-01

    Freeze-drying using a partial load is a common occurrence during the early manufacturing stages when insufficient amounts of active pharmaceutical ingredient (API) are available. In such cases, the immediate production needs are met by performing lyophilization with less than a full freeze dryer load. However, it is not obvious at what fractional load significant deviations from full load behavior begin. The objective of this research was to systematically study the effects of variation in product load on freeze drying behavior in laboratory, pilot and clinical scale freeze-dryers. Experiments were conducted with 5% mannitol (high heat and mass flux) and 5% sucrose (low heat and mass flux) at different product loads (100%, 50%, 10%, and 2%). Product temperature was measured in edge as well as center vials with thermocouples. Specific surface area (SSA) was measured by BET gas adsorption analysis and residual moisture was measured by Karl Fischer. In the lab scale freeze-dryer, the molar flux of inert gas was determined by direct flow measurement using a flowmeter and the molar flux of water vapor was determined by manometric temperature measurement (MTM) and tunable diode laser absorption spectroscopy (TDLAS) techniques. Comparative pressure measurement (capacitance manometer vs. Pirani) was used to determine primary drying time. For both 5% mannitol and 5% sucrose, primary drying time decreases and product temperature increases as the load on the shelves decreases. No systematic variation was observed in residual moisture and vapor composition as load decreased. Further, SSA data suggests that there are no significant freezing differences under different load conditions. Independent of dryer scale, among all the effects, variation in radiation heat transfer from the chamber walls to the product seems to be the dominant effect resulting in shorter primary drying time as the load on the shelf decreases (i.e., the fraction of edge vials increases).

  2. Modelling of the granular products vacuum freeze-dried process

    Directory of Open Access Journals (Sweden)

    S. T. Antipov

    2016-01-01

    Full Text Available In the work reviewed and simulated the process of vacuum freeze-drying of granular products with the destruction of the dried layer. As development of this direction serves the method based on removal of the dried product layer from a surface of a granule, formed in the form of spherical bodies and placed in the punched drum. After process of preliminary freezing of a granule get to the punched drum located in the vacuum drying chamber. In case of fixed hashing of granules of a product due to their friction among themselves and about drum walls a dry part of a product undergoes destruction and regularly separates from the refrigerated remaining balance. Process comes to an end when all product in a granule turns into dry powder. For creation of adequate model of process of drying, it is reasonable to consider a separate granule, but not a layer of granules in general, but taking into account influence of granules at each other in the course of drying. For this purpose, the scheme and mathematical description of radiation heat flux of the individual granules of the product. To account for the intermittent nature of exposure to granules suggested ratio and its two alternative approaches to its definition. As well as an algorithm for determining the coefficient that takes into account the one-sided irradiation of the pellets. Formulated mathematical model of the process the vacuum - freeze-drying of granular products, which is a one-dimensional parabolic boundary value problem with moving boundary. It includes the unsteady heat conduction equation, initial condition, boundary conditions and defining a movable boundary conditions. The sought quantities are the temperature field and the free boundary. Explained the origin of the functions of internal heat sources present in the equations of heat conduction.

  3. Effect of the rehydration medium on the recovery of freeze-dried lactic acid bacteria.

    Science.gov (United States)

    de Valdez, G F; de Giori, G S; de Ruiz Holgado, A P; Oliver, G

    1985-01-01

    Sixteen cultures of lactic acid bacteria were freeze-dried in 10% nonfat skim milk plus 0.75 M adonitol and rehydrated by using different rehydration media. Marked variations in their capacity to repair cellular damage after freeze-drying were observed among the species and strains under consideration. PMID:3911901

  4. Optimization Of Freeze-Dried Starter For Yogurt By Full Factorial Experimental Design

    Directory of Open Access Journals (Sweden)

    Chen He

    2015-12-01

    Full Text Available With the rapidly development of fermented milk product, it is significant for enhancing the performance of starter culture. This paper not only investigated the influence of anti-freeze factors and freeze-drying protective agents on viable count, freeze-drying survival rate and yield of Lactobacillus bulgaricus (LB and Streptococcus thermophilus (ST, but also optimized the bacteria proportion of freeze-dried starter culture for yogurt by full factorial experimental design. The results showed as following: the freeze-drying protective agents or anti-freeze factors could enhanced survival rate of LB and ST; the freeze-dried LB and ST powders containing both of anti-freeze factors and freeze-drying protective agents had higher viable count and freeze-drying survival rate that were 84.7% and 79.7% respectively; In terms of fermentation performance, the best group of freeze-dried starter for yogurt was the compound of LB3 and ST2.

  5. Novel Foams Based on Freeze-Dried Renewable Vital Wheat Gluten

    DEFF Research Database (Denmark)

    Blomfeldt, Thomas O.J.; Olsson, Richard T.; Menon, Mohan

    2010-01-01

    A new way of producing rigid or semi-rigid foams from vital wheat gluten using a freeze-drying process is reported. Water/gluten-based mixtures were frozen and freeze-dried. Different foam structures were obtained by varying the mixing process and wheat gluten concentration, or by adding glycerol...

  6. A Dynamic Design Space for Primary Drying During Batch Freeze-Drying

    DEFF Research Database (Denmark)

    Mortier, Séverine Thérèse F C; Van Bockstal, Pieter Jan; Nopens, Ingmar

    2016-01-01

    Biopharmaceutical products are emerging within the pharmaceutical industry. However, biopharmaceuticals are often unstable in aqueous solution. Freeze-drying (lyophilisation) is the preferred method to achieve a stable product with an increased shelf-life. During batch freeze-drying, there are only...

  7. Preliminary study on the freeze-drying of human bone marrow-derived mesenchymal stem cells*

    Science.gov (United States)

    Zhang, Shao-zhi; Qian, Huan; Wang, Zhen; Fan, Ju-li; Zhou, Qian; Chen, Guang-ming; Li, Rui; Fu, Shan; Sun, Jie

    2010-01-01

    Long-term preservation and easy transportation of human bone marrow-derived mesenchymal stem cells (hBM-MSCs) will facilitate their application in medical treatment and bioengineering. A pilot study on the freeze-drying of hBM-MSCs was carried out. hBM-MSCs were loaded with trehalose. The glass transition temperature of the freeze-drying suspension was measured to provide information for the cooling and primary drying experiment. After freeze-drying, various rehydration processes were tested. The highest recovery rate of hBM-MSCs was (69.33±13.08)%. Possible methods to improve freeze-drying outcomes are discussed. In conclusion, the present study has laid a foundation for the freeze-drying hBM-MSCs. PMID:21043058

  8. Freeze-drying-induced changes in the properties of graphene oxides

    International Nuclear Information System (INIS)

    Ham, Heon; Van Khai, Tran; Gil Na, Han; Jung Kwon, Yong; Yeon Cho, Hong; Woo Kim, Hyoun; Park, No-Hyung; So, Dae Sup; Lee, Joon-Woo

    2014-01-01

    We have characterized and evaluated changes in graphene oxide (GO) induced by means of freeze-drying. In order to evaluate these changes, we investigated the effects of freeze-drying and chemical reduction processes on the structure, morphology, chemical composition, and Raman properties of GO and reduced GO. The freeze-dried GO had a pore structure, maintaining a pored morphology even after thermal annealing. The freeze-dried samples were composed of a single folded nanosheet or a few nanosheets stacked and folded. The oxygen-containing functional groups were removed not only during the freeze-drying but also during the reduction processes, with an accompanying decrease in the average size of the sp 2 carbon domain (i.e. an increase in the I D /I G value). (papers)

  9. Development of freeze-dried miyeokguk, Korean seaweed soup, as space food sterilized by irradiation

    International Nuclear Information System (INIS)

    Song, Beom-Seok; Park, Jin-Gyu; Kim, Jae-Hun; Choi, Jong-Il; Ahn, Dong-Hyun; Hao, Chen; Lee, Ju-Woon

    2012-01-01

    The purpose of this study was to evaluate microbial populations, Hunter's color values (L ⁎ , a ⁎ , b ⁎ ) and the sensory quality of freeze-dried miyeokguk, Korean seaweed soup, in order to use it as space food. Microorganisms were not detected in non-irradiated freeze-dried miyeokguk within the detection limit of 1.00 log CFU/g. However, the microbial population in rehydrated miyeokguk was 7.01 log CFU/g after incubation at 35 °C for 48 h, indicating that freeze-dried miyeokguk was not sterilized by heat treatment during the preparation process. Bacteria in the freeze-dried miyeokguk were tentatively identified as Bacillus cereus, B. subtilis, Enterobacter hormaechei, and Ancinetobacter genomosp. using the 16S rDNA sequencing. In samples that were gamma-irradiated above 10 kGy, it was confirmed that all microorganisms were inactivated. Hunter's color values of the samples irradiated at doses less than 10 kGy were not significantly altered from their baseline appearance (p>0.05). Sensory evaluation showed that preference scores in all sensory properties decreased when freeze-dried miyeokguk was irradiated at doses greater than 10 kGy. Therefore, the results of this study suggest that gamma irradiation at 10 kGy is sufficient to sterilize freeze-dried miyeokguk without significant deterioration in the sensory quality, and thus, the freeze-dried and irradiated miyeokguk at 10 kGy fulfills the microbiological requirements as space food. - Highlights: ► 10 kGy gamma-irradiation is sufficient for sterilization of freeze-dried miyeokguk. ► Sensory quality of freeze-dried miyeokguk decreased after >10 kGy gamma irradiation. ► 10 kGy gamma-irradiation sterilizes freeze-dried miyeokguk and makes it optimal for use as space food.

  10. Role of freeze-drying in the presence of mannitol on the echogenicity of echogenic liposomes.

    Science.gov (United States)

    Kumar, Krishna N; Mallik, Sanku; Sarkar, Kausik

    2017-12-01

    Echogenic liposomes (ELIPs) are an excellent candidate for ultrasound activated therapeutics and imaging. Although multiple experiments have established their echogenicity, the underlying mechanism has remained unknown. However, freeze-drying in the presence of mannitol during ELIP preparation has proved critical to ensuring echogenicity. Here, the role of this key component in the preparation protocol was investigated by measuring scattering from freshly prepared freeze-dried aqueous solution of mannitol-and a number of other excipients commonly used in lyophilization-directly dispersed in water without any lipids in the experiment. Mannitol, meso-erythritol, glycine, and glucose that form a highly porous crystalline phase upon freeze-drying generated bubbles resulting in strong echoes during their dissolution. On the other hand, sucrose, trehalose, and xylitol, which become glassy while freeze-dried, did not. Freeze-dried mannitol and other crystalline substances, if thawed before being introduced into the scattering volume, did not produce echogenicity, as they lost their crystallinity in the thawed state. The echogenicity disappeared in a degassed environment. Higher amounts of sugar in the original aqueous solution before freeze-drying resulted in higher echogenicity because of the stronger supersaturation and crystallinity. The bubbles created by the freeze-dried mannitol in the ELIP formulation play a critical role in making ELIPs echogenic.

  11. Simulation of the process kinetics and analysis of physicochemical properties in the freeze drying of kale

    Science.gov (United States)

    Dziki, Dariusz; Polak, Renata; Rudy, Stanisław; Krzykowski, Andrzej; Gawlik-Dziki, Urszula; Różyło, Renata; Miś, Antoni; Combrzyński, Maciej

    2018-01-01

    Investigations were performed to study the freeze-drying process of kale (Brassica oleracea L. var acephala). The process of freeze-drying was performed at temperatures of 20, 40, and 60°C for whole pieces of leaves and for pulped leaves. The kinetics of the freeze-drying of both kale leaves and kale pulp were best described by the Page model. The increasing freeze-drying temperature from 20 to 60°C induced an approximately two-fold decrease in the drying time. Freeze-drying significantly increased the value of the lightness, delta Chroma, and browning index of kale, and had little influence on the hue angle. The highest increase in the lightness and delta Chroma was observed for whole leaves freeze-dried at 20°C. An increase in the drying temperature brought about a slight decrease in the lightness, delta Chroma and the total colour difference. Pulping decreased the lightness and hue angle, and increased browning index. Freeze-drying engendered a slight decrease in the total phenolics content and antioxidant activity, in comparison to fresh leaves. The temperature of the process and pulping had little influence on the total phenolics content and antioxidant activity of dried kale, but significantly decreased the contents of chlorophyll a and chlorophyll b.

  12. Development of freeze-dried miyeokguk, Korean seaweed soup, as space food sterilized by irradiation

    Science.gov (United States)

    Song, Beom-Seok; Park, Jin-Gyu; Kim, Jae-Hun; Choi, Jong-Il; Ahn, Dong-Hyun; Hao, Chen; Lee, Ju-Woon

    2012-08-01

    The purpose of this study was to evaluate microbial populations, Hunter's color values (L*, a*, b*) and the sensory quality of freeze-dried miyeokguk, Korean seaweed soup, in order to use it as space food. Microorganisms were not detected in non-irradiated freeze-dried miyeokguk within the detection limit of 1.00 log CFU/g. However, the microbial population in rehydrated miyeokguk was 7.01 log CFU/g after incubation at 35 °C for 48 h, indicating that freeze-dried miyeokguk was not sterilized by heat treatment during the preparation process. Bacteria in the freeze-dried miyeokguk were tentatively identified as Bacillus cereus, B. subtilis, Enterobacter hormaechei, and Ancinetobacter genomosp. using the 16S rDNA sequencing. In samples that were gamma-irradiated above 10 kGy, it was confirmed that all microorganisms were inactivated. Hunter's color values of the samples irradiated at doses less than 10 kGy were not significantly altered from their baseline appearance (p>0.05). Sensory evaluation showed that preference scores in all sensory properties decreased when freeze-dried miyeokguk was irradiated at doses greater than 10 kGy. Therefore, the results of this study suggest that gamma irradiation at 10 kGy is sufficient to sterilize freeze-dried miyeokguk without significant deterioration in the sensory quality, and thus, the freeze-dried and irradiated miyeokguk at 10 kGy fulfills the microbiological requirements as space food.

  13. Chromosomal integrity of freeze-dried mouse spermatozoa after 137Cs γ-ray irradiation

    International Nuclear Information System (INIS)

    Kusakabe, Hirokazu; Kamiguchi, Yujiroh

    2004-01-01

    This study demonstrated that freeze-dried mouse spermatozoa possess strong resistance to 137 Cs γ-ray irradiation at doses of up to 8 Gy. Freeze-dried mouse spermatozoa were rehydrated and injected into mouse oocytes with an intracytoplasmic sperm injection (ICSI) technique. Most oocytes can be activated after ICSI by using spermatozoa irradiated with γ-rays before and after freeze-drying. Sperm chromosome complements were analyzed at the first cleavage metaphase. Chromosome aberrations increased in a dose-dependent manner in the spermatozoa irradiated before freeze-drying. However, no increase in oocytes with chromosome aberrations was observed when fertilized by spermatozoa that had been irradiated after freeze-drying, as compared with freeze-dried spermatozoa that had not been irradiated. These results suggest that both the chromosomal integrity of freeze-dried spermatozoa, as well as their ability to activate oocytes, were protected from γ-ray irradiation at doses at which chromosomal damage is found to be strongly induced in spermatozoa suspended in solution

  14. Mechanisms of deterioration of nutrients. [freeze drying methods for space flight food

    Science.gov (United States)

    Karel, M.; Flink, J. M.

    1974-01-01

    Methods are reported by which freeze dried foods of improved quality will be produced. The applicability of theories of flavor retention has been demonstrated for a number of food polymers, both proteins and polysacchardies. Studies on the formation of structures during freeze drying have been continued for emulsified systems. Deterioration of organoleptic quality of freeze dried foods due to high temperature heating has been evaluated and improved procedures developed. The influence of water activity and high temperature on retention of model flavor materials and browning deterioration has been evaluated for model systems and food materials.

  15. Refurbishing of a Freeze Drying Machine, used in Nuclear Medicine for Radiopharmaceuticals Production

    International Nuclear Information System (INIS)

    Gaytan-Gallardo, E.; Desales-Galeana, G.

    2006-01-01

    The refurbishing of a freeze drying machine used in the radiopharmaceuticals production, applied in nuclear medicine in the Radioactive Materials Department of the Nuclear Research National Institute in Mexico (ININ in Spanish), is presented. The freeze drying machine was acquired in the 80's decade and some components started having problems. Then it was necessary to refurbish this equipment by changing old cam-type temperature controllers and outdated recording devices, developing a sophisticated software system that substitutes those devices. The system is composed by a freeze drying machine by Hull, AC output modules for improved temperature control, a commercial data acquisition card, and the software system

  16. Sperm preservation by freeze-drying for the conservation of wild animals.

    Directory of Open Access Journals (Sweden)

    Takehito Kaneko

    Full Text Available Sperm preservation is a useful technique for the maintenance of biological resources in experimental and domestic animals, and in wild animals. A new preservation method has been developed that enables sperm to be stored for a long time in a refrigerator at 4 °C. Sperm are freeze-dried in a solution containing 10 mM Tris and 1 mM EDTA. Using this method, liquid nitrogen is not required for the storage and transportation of sperm. We demonstrate that chimpanzee, giraffe, jaguar, weasel and the long-haired rat sperm remain viable after freeze-drying. In all species, pronuclei were formed after the injection of freeze-dried sperm into the mouse oocytes. Although preliminary, these results may be useful for the future establishment of "freeze-drying zoo" to conserve wild animals.

  17. Sperm Preservation by Freeze-Drying for the Conservation of Wild Animals

    Science.gov (United States)

    Kaneko, Takehito; Ito, Hideyuki; Sakamoto, Hidefusa; Onuma, Manabu; Inoue-Murayama, Miho

    2014-01-01

    Sperm preservation is a useful technique for the maintenance of biological resources in experimental and domestic animals, and in wild animals. A new preservation method has been developed that enables sperm to be stored for a long time in a refrigerator at 4°C. Sperm are freeze-dried in a solution containing 10 mM Tris and 1 mM EDTA. Using this method, liquid nitrogen is not required for the storage and transportation of sperm. We demonstrate that chimpanzee, giraffe, jaguar, weasel and the long-haired rat sperm remain viable after freeze-drying. In all species, pronuclei were formed after the injection of freeze-dried sperm into the mouse oocytes. Although preliminary, these results may be useful for the future establishment of “freeze-drying zoo” to conserve wild animals. PMID:25409172

  18. Sperm preservation by freeze-drying for the conservation of wild animals.

    Science.gov (United States)

    Kaneko, Takehito; Ito, Hideyuki; Sakamoto, Hidefusa; Onuma, Manabu; Inoue-Murayama, Miho

    2014-01-01

    Sperm preservation is a useful technique for the maintenance of biological resources in experimental and domestic animals, and in wild animals. A new preservation method has been developed that enables sperm to be stored for a long time in a refrigerator at 4 °C. Sperm are freeze-dried in a solution containing 10 mM Tris and 1 mM EDTA. Using this method, liquid nitrogen is not required for the storage and transportation of sperm. We demonstrate that chimpanzee, giraffe, jaguar, weasel and the long-haired rat sperm remain viable after freeze-drying. In all species, pronuclei were formed after the injection of freeze-dried sperm into the mouse oocytes. Although preliminary, these results may be useful for the future establishment of "freeze-drying zoo" to conserve wild animals.

  19. Microstructure study of a material on the basis of YSZ obtained be freeze-drying

    International Nuclear Information System (INIS)

    Rizea, A.; Abrudeanu, M.; Petot, C.; Petot Ervas, G.

    2001-01-01

    Freeze-drying is a dehydration proceeding of the products in a frozen state, which is based on the ice sublimation process. It is a method, which leads to a very good homogeneity of the products and it allows obtaining very fine powders, which directs to reducing the sintering temperature. Freeze drying always supposes three stages: - freezing, sublimation and absorption of the residual water. The preparation of ZrO 20.91 Y 2 O 30.09 samples proceeds through the following stages: - a. solution preparation; b. solution spraying (into small droplets in liquid nitrogen); c. freeze drying processing; d. calcination of the freeze dried powder; e. powder compacting; f. sintering at four different temperature. The different structure of samples with different density are characterized on basis of micrographs. The results of these analyses are presented, discussed and explained through the chemical composition of the samples

  20. Model-based optimization of the primary drying step during freeze-drying

    DEFF Research Database (Denmark)

    Mortier, Séverine Thérèse F.C.; Van Bockstal, Pieter-Jan; Nopens, Ingmar

    2015-01-01

    Since large molecules are considered the key driver for growth of the pharmaceutical industry, the focus of the pharmaceutical industry is shifting from small molecules to biopharmaceuticals: around 50% of the approved biopharmaceuticals are freeze-dried products. Therefore, freeze- drying...... is an important technology to stabilise biopharmaceutical drug products which are unstable in an aqueous solution. However, the freeze-drying process is an energy and time-consuming process. The use of mechanistic modelling to gather process knowledge can assist in optimisation of the process parameters during...... the operation of the freeze-drying process. By applying a dynamic shelf temperature and chamber pressure, which are the only controllable process variables, the processing time can be decreased by a factor 2 to 3....

  1. Freeze-drying and related preparation techniques for biological microprobe analysis

    International Nuclear Information System (INIS)

    Wroblewski, R.; Wroblewski, J.; Anniko, M.; Edstroem, L.P.

    1985-01-01

    An X-ray microanalytical and morphological investigation has been carried out on rapidly frozen, freeze-dried or freeze-substituted tissues. A comparison was made between different embedding and polymerization procedures following freeze-substitution and freeze-drying. The investigation also included an analysis of specimens infiltrated, embedded and polymerized by ultraviolet irradiation at low temperatures with Lowicryl HM20. The morphological preservation of Lowicryl embedded tissue was adequate for the identification of different cell structures like nuclei, mitochondria, lysosomes and different types of endoplasmic reticulum. X-ray microanalytical investigation of low temperature embedded material displayed an elemental composition of cells and organelles similar to that found in freeze-dried cyosections. Compared with freeze-dried cryosections, low temperature embedded material could be sectioned for light microscopy and area of interest chosen for further thin sectioning. This is of great importance in work with tissues with complicated morphology and heterogenous cell populations

  2. Freeze-drying of ampicillin solid lipid nanoparticles using mannitol as cryoprotectant

    Directory of Open Access Journals (Sweden)

    Faezeh Alihosseini

    2015-12-01

    Full Text Available abstract Solid lipid nanoparticles (SLNs are interesting colloidal drug-delivery systems, since they have all the advantages of the lipid and polymeric nanoparticles. Freeze-drying is a widely used process for improving the stability of SLNs. Cryoprotectants have been used to decrease SLN aggregations during freeze-drying. In this study Ampicillin was chosen to be loaded in a cholesterol carrier with nano size range. To support the stability of SLNs, freeze-drying was done using mannitol. Particle size, drug release profile and antibacterial effects were studied after freeze-drying in comparison with primary SLNs. Preparations with 5% mannitol showed the least particle size enlargement. The average particle size was 150 and 187 nm before and after freeze-drying, respectively. Freeze-drying did not affect the release profile of drug loaded nanopartilces. Also our study showed that lyophilization did not change the antimicrobial effect of ampicillin SLNs. DSC analysis showed probability of chemical interaction between ampicillin and cholesterol.

  3. Effects of six substances on the growth and freeze-drying of Lactobacillus delbrueckii subsp. bulgaricus.

    Science.gov (United States)

    Chen, He; Huang, Jie; Shi, Xiaoyu; Li, Yichao; Liu, Yu

    2017-01-01

    The efficacy of Lactobacillus delbrueckii subsp. bulgaricus as starter cultures for the dairy industry depends largely on the number of viable and active cells. Freeze-drying is the most convenient and successful method to preserve the bacterial cells. However, not all strains survived during freeze-drying. The effects of six substances including NaCl, sorbitol, mannitol, mannose, sodium glutamate, betaine added to the MRS medium on the growth and freeze-drying survival rate and viable counts of Lb. delbrueckii subsp. bulgaricus were studied through a single-factor test and Plackett-Burman design. Subsequently, the optimum freeze-drying conditions of Lb. delbrueckii subsp. bulgaricus were determined. Lb. delbrueckii subsp. bulgaricus survival rates were up to the maximum of 42.7%, 45.4%, 23.6%, while the concentrations of NaCl, sorbitol, sodium glutamate were 0.6%, 0.15%, 0.09%, respectively. In the optimum concentration, the viable counts in broth is 6.1, 6.9, 5.13 (×108 CFU/mL), respectively; the viable counts in freeze-drying power are 3.09, 5.2, 2.7 (×1010 CFU/g), respectively. Three antifreeze factors including NaCl, sorbitol, sodium glutamate have a positive effect on the growth and freeze-drying of Lb. delbrueckii subsp. bulgaricus. The results are beneficial for developing Lb. delbrueckii subsp. bulgaricus.

  4. Spray freeze drying as an alternative technique for lyophilization of polymeric and lipid-based nanoparticles.

    Science.gov (United States)

    Ali, Mohamed Ehab; Lamprecht, Alf

    2017-01-10

    The use of nanoparticles for drug delivery is still restricted by their limited stability when stored in an aqueous medium. Freeze drying is the standard method for long-term storage of colloidal nanoparticles; however the method needs to be elaborated for each formulation. Spray freeze drying (SFD) is proposed here as a promising alternative for lyophilizing colloidal nanoparticles. Different types of polymeric and lipid nanoparticles were prepared and characterized. Afterwards, samples were spray freeze dried by spraying into a column of cold air with a constant concentration of different cryoprotectants, and the frozen spherules were collected for further freeze drying. Similar samples were prepared using the commonly used technique, freeze drying, as controls. Using SFD, fast-dissolving, spherical and porous nanocomposite microparticles with remarkably high flowability (CI≤10) were produced. On the contrary to similar samples prepared using the freeze drying technique, the investigated polymeric and lipid nanoparticles were completely reconstituted (S f /S i ratio <1.5) after SFD. SFD proved to be an effective platform for improving the long-term stability of colloidal nanoparticles. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Cell growth and resistance of Lactococcus lactis subsp. lactis TOMSC161 following freezing, drying and freeze-dried storage are differentially affected by fermentation conditions.

    Science.gov (United States)

    Velly, H; Fonseca, F; Passot, S; Delacroix-Buchet, A; Bouix, M

    2014-09-01

    To investigate the effects of fermentation parameters on the cell growth and on the resistance to each step of the freeze-drying process of Lactococcus lactis subsp. lactis TOMSC161, a natural cheese isolate, using a response surface methodology. Cells were cultivated at different temperatures (22, 30 and 38°C) and pH (5·6, 6·2 and 6·8) and were harvested at different growth phases (0, 3 and 6 h of stationary phase). Cultivability and acidification activity losses of Lc. lactis were quantified after freezing, drying, 1 and 3 months of storage at 4 and 25°C. Lactococcus lactis was not damaged by freezing but was sensitive to drying and to ambient temperature storage. Moreover, the fermentation temperature and the harvesting time influenced the drying resistance of Lc. lactis. Lactococcus lactis cells grown in a whey-based medium at 32°C, pH 6·2 and harvested at late stationary phase exhibited both an optimal growth and the highest resistance to freeze-drying and storage. A better insight on the individual and interaction effects of fermentation parameters made it possible the freeze-drying and storage preservation of a sensitive strain of technological interest. Evidence on the particularly damaging effect of the drying step and the high-temperature storage is presented. © 2014 The Society for Applied Microbiology.

  6. New Processes for Freeze-Drying in Dual-Chamber Systems.

    Science.gov (United States)

    Werk, T; Ludwig, I S; Luemkemann, J; Huwyler, J; Mahler, H-C; Haeuser, C R; Hafner, M

    2016-01-01

    Dual-chamber systems can offer self-administration and home care use for lyophilized biologics. Only a few products have been launched in dual-chamber systems so far-presumably due to dual-chamber systems' complex and costly drug product manufacturing process. Within this paper, two improved processes (both based on tray filling technology) for freeze-drying pharmaceuticals in dual-chamber systems are described. Challenges with regards to heat transfer were tackled by (1) performing the freeze-drying step in a needle-down orientation in combination with an aluminum block, or (2) freeze-drying the drug product "externally" in a metal cartridge with subsequent filling of the lyophilized cake into the dual-chamber system. Metal-mediated heat transfer was shown to be efficient in both cases and batch (unit-to-unit) homogeneity with regards to sublimation rate was increased. It was difficult to influence ice crystal size using different methods when in use with an aluminum block due to its heat capacity. Using such a metal carrier implies a large heat capacity leading to relatively small ice crystals. Compared to the established process, drying times were reduced by half using the new processes. The drying time was, however, longer for syringes compared to vials due to the syringe design (long and slim). The differences in drying times were less pronounced for aggressive drying cycles. The proposed processes may help to considerably decrease investment costs into dual-chamber system fill-finish equipment. Dual-chamber syringes offer self-administration and home care use for freeze-dried pharmaceuticals. Only a few products have been launched in dual-chamber syringes so far-presumably due to their complex and costly drug product manufacturing process. In this paper two improved processes for freeze-drying pharmaceuticals in dual-chamber syringes are described. The major challenge of freeze-drying is to transfer heat through a vacuum. The proposed processes cope with this

  7. Assessing storage of stability and mercury reduction of freeze-dried Pseudomonas putida within different types of lyoprotectant

    Science.gov (United States)

    Azoddein, Abdul Aziz Mohd; Nuratri, Yana; Azli, Faten Ahada Mohd; Bustary, Ahmad Bazli

    2017-12-01

    Pseudomonas putida is a potential strain in biological treatment to remove mercury contained in the effluent of petrochemical industry due to its mercury reductase enzyme that able to reduce ionic mercury to elementary mercury. Freeze-dried P. putida allows easy, inexpensive shipping, handling and high stability of the product. This study was aimed to freeze dry P. putida cells with addition of lyoprotectant. Lyoprotectant was added into the cells suspension prior to freezing. Dried P. putida obtained was then mixed with synthetic mercury. Viability of recovery P. putida after freeze dry was significantly influenced by the type of lyoprotectant. Among the lyoprotectants, tween 80/ sucrose was found to be the best lyoprotectant. Sucrose was able to recover more than 78% (6.2E+09 CFU/ml) of the original cells (7.90E+09CFU/ml) after freeze dry and able to retain 5.40E+05 viable cells after 4 weeks storage at 4 °C without vacuum. Polyethylene glycol (PEG) pre-treated freeze dried cells and broth pre-treated freeze dried cells after the freeze-dry process recovered more than 64% (5.0 E+09CFU/ml) and >0.1% (5.60E+07CFU/ml). Freeze-dried P. putida cells in PEG and broth cannot survive after 4 weeks storage. Freeze dry also does not really change the pattern of growth P. putida but extension of lag time was found 1 hour after 3 weeks of storage. Additional time was required for freeze-dried P. putida cells to recover before introducing freeze-dried cells to more complicated condition such as mercury solution. The maximum mercury reduction of PEG pre-treated freeze-dried cells after freeze dry and after storage of 3 weeks was 17.91 %. The maximum of mercury reduction of tween 80/sucrose pre-treated freeze-dried cells after freeze dry and after storage 3 weeks was 25.03%. Freeze dried P. putida was found to have lower mercury reduction compare to the fresh P. putida that has been grown in agar. Result from this study may be beneficial and useful as initial reference before

  8. Physicochemical interaction mechanism between nanoparticles and tetrasaccharides (stachyose) during freeze-drying.

    Science.gov (United States)

    Kamiya, Seitaro; Nakashima, Kenichiro

    2017-12-01

    Nanoparticle suspensions are thermodynamically unstable and subject to aggregation. Freeze-drying on addition of saccharides is a useful method for preventing aggregation. In the present study, tetrasaccharides (stachyose) was employed as an additive. In addition, we hypothesize the interactive mechanism between stachyose and the nanoparticles during freeze-drying for the first time. The mean particle size of the rehydrated freeze-dried stachyose-containing nanoparticles (104.7 nm) was similar to the initial particle size before freeze-drying (76.8 nm), indicating that the particle size had been maintained. The mean particle size of the rehydrated normal-dried stachyose-containing nanoparticles was 222.2 nm. The powder X-ray diffraction of the freeze-dried stachyose-containing nanoparticles revealed a halo pattern. The powder X-ray diffraction of the normally dried stachyose-containing nanoparticles produced mainly a halo pattern and a partial peak. These results suggest an interaction between the nanoparticles and stachyose, and that this relationship depends on whether the mixture is freeze-dried or dried normally. In the case of normal drying, although most molecules cannot move rapidly thereby settling irregularly, some stachyose molecules can arrange regularly leading to some degree of crystallization and potentially some aggregation. In contrast, during freeze-drying, the moisture sublimed, while the stachyose molecules and nanoparticles were immobilized in the ice. After sublimation, stachyose remained in the space occupied by water and played the role of a buffer material, thus preventing aggregation.

  9. Synergistic effects of surfactants and sugars on lipoplex stability during freeze-drying and rehydration.

    Science.gov (United States)

    Yu, Jinxiang; Anchordoquy, Thomas J

    2009-09-01

    The stability of nonviral vectors during freeze-drying has been well-studied, and it has been established that sugars can protect lipoplexes during freeze-drying. However low levels of damage are often observed after freeze-drying, and this damage is more evident in dilute lipoplex preparations. By investigating the stability of lipoplexes after each step in the freeze-drying cycle (i.e., freezing, primary drying, and secondary drying), we strive to understand the mechanisms responsible for damage and identify improved stabilization strategies. N-(1-(2,3-dioleoyloxy)propyl)-N,N,N-trimethylammonium chloride (DOTAP)-cholesterol/plasmid DNA lipoplexes were prepared at an equimolar DOTAP-cholesterol ratio, and a 3:1 DOTAP(+)-DNA(-) charge ratio. Our experiments indicate that despite sufficient levels of "stabilizing" sugars, significant damage is still evident when dilute lipoplex preparations are subjected to freeze-drying. Analysis of the different stages of freeze-drying suggests that significant damage occurs during freezing, and that sugars have a limited capacity to protect against this freezing-induced damage. Similar effects have been observed in studies with proteins, and surfactants have been employed in protein formulations to protect against surface-induced damage, for example, at the ice crystal, solid, air, or sugar glass surfaces. However, the use of surfactants in a lipid-based formulation is inherently risky due to the potential for altering/solubilizing the lipid delivery vehicle. Our data indicate that judicious use of surfactants can reduce surface-induced damage and result in better preservation of lipoplex size and transfection activity after freeze-drying.

  10. Effect of Freeze-Drying on the Antioxidant Compounds and Antioxidant Activity of Selected Tropical Fruits

    Directory of Open Access Journals (Sweden)

    Muhammad Redzuan Hairuddin

    2011-07-01

    Full Text Available The effects of freeze-drying on antioxidant compounds and antioxidant activity of five tropical fruits, namely starfruit (Averrhoa carambola L., mango (Mangifera indica L., papaya (Carica papaya L., muskmelon (Cucumis melo L., and watermelon Citruluss lanatus (Thunb. were investigated. Significant (p < 0.05 differences, for the amounts of total phenolic compounds (TPC, were found between the fresh and freeze-dried fruit samples, except muskmelon. There was no significant (p > 0.05 change, however, observed in the ascorbic acid content of the fresh and freeze-dried fruits. Similarly, freeze-drying did not exert any considerable effect on β-carotene concentration of fruits, except for mango and watermelon, where significantly (p < 0.05 higher levels were detected in the fresh samples. The results of DPPH (2,2-diphenyl-1-picrylhydrazyl radical scavenging and reducing power assays revealed that fresh samples of starfruit and mango had relatively higher antioxidant activity. In case of linoleic acid peroxidation inhibition measurement, a significant (p < 0.05 but random variation was recorded between the fresh and freeze-dried fruits. Overall, in comparison to β-carotene and ascorbic acid, a good correlation was established between the result of TPC and antioxidant assays, indicating that phenolics might have been the dominant compounds contributing towards the antioxidant activity of the fruits tested.

  11. Rehydration of freeze-dried and convective dried boletus edulis mushrooms: effect on some quality parameters.

    Science.gov (United States)

    Hernando, I; Sanjuán, N; Pérez-Munuera, I; Mulet, A

    2008-10-01

    Quality of rehydrated products is a key aspect linked to rehydration conditions. To assess the effect of rehydration temperature on some quality parameters, experiments at 20 and 70 degrees C were performed with convective dried and freeze-dried Boletus edulis mushrooms. Rehydration characteristics (through Peleg's parameter, k(1), and equilibrium moisture, W(e)), texture (Kramer), and microstructure (Cryo-Scanning Electron Microscopy) were evaluated. Freeze-dried samples absorbed water more quickly and attained higher W(e) values than convective dried ones. Convective dehydrated samples rehydrated at 20 degrees C showed significantly lower textural values (11.9 +/- 3.3 N/g) than those rehydrated at 70 degrees C (15.7 +/- 1.2 N/g). For the freeze-dried Boletus edulis, the textural values also exhibited significant differences, being 8.2 +/- 1.3 and 10.5 +/- 2.3 N/g for 20 and 70 degrees C, respectively. Freeze-dried samples showed a porous structure that allows rehydration to take place mainly at the extracellular level. This explains the fact that, regardless of temperature, freeze-dried mushrooms absorbed water more quickly and reached higher W(e) values than convective dried ones. Whatever the dehydration technique used, rehydration at 70 degrees C produced a structural damage that hindered water absorption; consequently lower W(e) values and higher textural values were attained than when rehydrating at 20 degrees C.

  12. Freeze-dried spermatozoa: An alternative biobanking option for endangered species.

    Science.gov (United States)

    Anzalone, Debora Agata; Palazzese, Luca; Iuso, Domenico; Martino, Giuseppe; Loi, Pasqualino

    2018-03-01

    In addition to the iconic wild species, such as the pandas and Siberian tigers, an ever-increasing number of domestic species are also threatened with extinction. Biobanking of spermatozoa could preserve genetic heritages of extinct species, and maintain biodiversity of existing species. Because lyophilized spermatozoa retain fertilizing capacity, the aim was to assess whether freeze-dried spermatozoa are an alternative option to save endangered sheep breeds. To achieve this objective, semen was collected from an Italian endangered sheep breed (Pagliarola), and a biobank of cryopreserved and freeze-dried spermatozoa was established, and evaluated using IVF (for frozen spermatozoa) and ICSI procedures (for frozen and freeze-dried spermatozoa). As expected, the fertilizing capacity of cryopreserved Pagliarola's spermatozoa was comparable to commercial semen stocks. To evaluate the activating capability of freeze-dried spermatozoa, 108 MII sheep oocytes were subjected to ICSI, and allocated to two groups: 56 oocytes were activated by incubation with ionomycin (ICSI-FDSa) and 52 were not activated (ICSI-FDSna). Pronuclear formation (2PN) was investigated at 14-16 h after ICSI in fixed presumptive zygotes. Only artificially activated oocytes developed into blastocysts after ICSI. In the present study, freeze-dried ram spermatozoa induced blastocyst development following ICSI at a relatively high proportion, providing evidence that sperm lyophilization is an alternative, low cost storage option for biodiversity preservation of domestic species. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Nanocrystals-based Macroporous Materials Synthesized by Freeze-drying Combustion

    International Nuclear Information System (INIS)

    Yan, Ruiqiang; Chen, Yu; Lin, Ye; Chen, Fanglin

    2016-01-01

    We present a novel freeze-drying combustion method for synthesis of macroporous powders with nano-network, using Sm 0.2 Ce 0.8 O 1.9 (SDC) as an example. The metal nitrate salt solution mixed with glycine is frozen to form homogeneous nitrate/glycine mixture and then freeze-dried through sublimation of ice crystals. Upon combustion of the freeze-dried mixture, SDC powders with macroporous microstructure consisting of 10–20 nm nanocrystals, high surface area and excellent sinterability are achieved. High resolution transmission electron microscopy (HRTEM) analysis indicates that nanodomains due to aggregation/segregation of dopants in the SDC powders obtained from freeze-drying combustion are much smaller than those in the SDC powders synthesized by the conventional nitrate solution combustion approach, demonstrating better elemental homogeneity and improved conductivity. Using low cost precursors and simple processing conditions, freeze-drying combustion can be a versatile method to synthesize nanocrystalline powders with excellent composition homogeneity for broad applications.

  14. Preparation and evaluation of freeze-dried Mag3 kits for 99m Tc-labelling

    International Nuclear Information System (INIS)

    El-Mohty, A.A.; El-Ghany, E.A.; El-Kolaly, M.T.; Raieh, M.; EL-Bary, A.A.

    1996-01-01

    The freeze-dried Mag 3 kits were designed for both ligand trans chelation and direct labelling techniques. The solution of Sn-Mag 3 was sterilized by 0.22 μU mill pore filtration and dispensed in a laminar flow hood (1 m I / vial) then, the vials were introduced to the lyophilized. The process of lyophilization was continued for 24 hours. At end of the cycle, the vials were closed under nitrogen. The moisture content of the freeze-dried Mag 3 kits was determined and it was found equal to 0.1% also, the losses of tin (II) during the freeze-drying cycle did not exceed 5%. It was found that the Mag 3 freeze-dried kits were sterile, pyrogen free and does not have any unexpected toxicity. The prepared Mag 3 freeze-dried kits have high radiochemical purity > 97% and high stability for more than 8 h after labelling. The biodistribution shows rapid renal excretion at 15 min post injection. 3 figs., 4 tabs

  15. Stability evaluation of freeze-dried Lactobacillus paracasei subsp. tolerance and Lactobacillus delbrueckii subsp. bulgaricus in oral capsules

    OpenAIRE

    Jalali, M.; Abedi, D.; Varshosaz, J.; Najjarzadeh, M.; Mirlohi, M.; Tavakoli, N.

    2012-01-01

    Freeze-drying is a common preservation technology in the pharmaceutical industry. Various studies have investigated the effect of different cryoprotectants on probiotics during freeze-drying. However, information on the effect of cryoprotectants on the stability of some Lactobacillus strains during freeze-drying seems scarce. Therefore, the aim of the present study was to establish production methods for preparation of oral capsule probiotics containing Lactobacillus paracasei subsp. toleranc...

  16. Modelling and simulation of a moving interface problem: freeze drying of black tea extract

    Science.gov (United States)

    Aydin, Ebubekir Sıddık; Yucel, Ozgun; Sadikoglu, Hasan

    2017-06-01

    The moving interface separates the material that is subjected to the freeze drying process as dried and frozen. Therefore, the accurate modeling the moving interface reduces the process time and energy consumption by improving the heat and mass transfer predictions during the process. To describe the dynamic behavior of the drying stages of the freeze-drying, a case study of brewed black tea extract in storage trays including moving interface was modeled that the heat and mass transfer equations were solved using orthogonal collocation method based on Jacobian polynomial approximation. Transport parameters and physical properties describing the freeze drying of black tea extract were evaluated by fitting the experimental data using Levenberg-Marquardt algorithm. Experimental results showed good agreement with the theoretical predictions.

  17. Effect of freeze-drying on the antioxidant compounds and antioxidant activity of selected tropical fruits.

    Science.gov (United States)

    Shofian, Norshahida Mohamad; Hamid, Azizah Abdul; Osman, Azizah; Saari, Nazamid; Anwar, Farooq; Dek, Mohd Sabri Pak; Hairuddin, Muhammad Redzuan

    2011-01-01

    The effects of freeze-drying on antioxidant compounds and antioxidant activity of five tropical fruits, namely starfruit (Averrhoa carambola L.), mango (Mangifera indica L.), papaya (Carica papaya L.), muskmelon (Cucumis melo L.), and watermelon Citruluss lanatus (Thunb.) were investigated. Significant (p 0.05) change, however, observed in the ascorbic acid content of the fresh and freeze-dried fruits. Similarly, freeze-drying did not exert any considerable effect on β-carotene concentration of fruits, except for mango and watermelon, where significantly (p correlation was established between the result of TPC and antioxidant assays, indicating that phenolics might have been the dominant compounds contributing towards the antioxidant activity of the fruits tested.

  18. Screening freeze-drying cryoprotectants for Saccharomyces boulardii by Plackett-Burman design

    Directory of Open Access Journals (Sweden)

    He CHEN

    2016-12-01

    Full Text Available As a lyophilized product, Saccharomyces boulardii has been commonly used to treat diarrhea in adults. However, there are few studies focusing on the preparation of its freeze-drying powder. This paper investigated the effect of lyoprotectants on the freeze-drying survival rate and the number of viable cells for vacuum freezedried powder of S. boulardii. Single factor experiment and Plackett-Burman design were conducted to obtain the optimal compound lyoprotectant formulations. The result showed that lactose, trehalose and sodium glutamate could significantly enhance the freeze-drying survival rate of S. boulardii. Meanwhile, all these three lyoprotectants showed positive effect on the freezedrying survival rate of the yeast, and the optimal lyoprotectant composition for S. boulardii was as follows: 18g/100mL lactose, 18g/100mL trehalose and 3g/100mL sodium glutamate.

  19. Karakterisasi Kompleks Inklusi Asam Mefenamat - β -Siklodekstrin yang Dibuat dengan Metode Freeze Drying

    Directory of Open Access Journals (Sweden)

    Dwi Setyawan

    2012-10-01

    Full Text Available Characterization of mefenamic acid-β-cyclodextrin inclusion complexes by freeze drying method had been studied. Solid state mefenamic acid- β-cyclodextrin inclusion complex prepared by freeze drying method in 1:1 molar ratio. Mefenamic acid, β-cyclodextrin, mefenamic acid-β-cyclodextrin physical mixture and inclusion complexes were charac­terized by Powder X-ray Diffraction (PXRD, Fourier Transform Infrared Spectroscopy (FTIR , Differential Thermal Analyzer (DTA and dissolution studies. The results showed the formation of inclusion complex between mefenamic acid and β-cyclodextrin. In vitro dis­solution rate studies of mefenamic acid, mefenamic acid-β-cyclodextrin physical mixture and inclusion complex were conducted using basket method and water as dissolution medium. Mefenamic acid-β-cyclodextrin inclusion complex showed increasing dissolution rate compared to mefenamic acid-β-cyclodextrin physical mixture and mefenamic acid.   Key words: mefenamic acid, β-cyclodextrin, freeze drying, inclusion complex, dissolution rate

  20. Method of reprocessing nuclear fuel using vacuum freeze-drying method

    International Nuclear Information System (INIS)

    Otsuka, Katsuyuki; Kondo, Isao.

    1989-01-01

    Solutions of plutonium nitrate and uranyl nitrate, spent solvents and liquid wastes separated by the treatment in the solvent extractant steps in the wet processing steps of re-processing plants or fuel fabrication plants are processed by means of freeze-drying under vacuum. Then, the solutions of plutonium nitrate and uranyl nitrate are separated into nitrates and liquid condensates and the spent solvents are freeze-dried. Thus, they are separated into tri-n-butyl phosphate, diester, monoester and n-dodecane and the liquid wastes are processed by means of freeze-drying and separated into liquids and residues. In this way, since sodium carbonate, etc. are not used, the amount of resultant liquid wastes is reduced and sodium is not contained in liquid wastes sent to an asphalt solidification step and a vitrification step, the processing steps can be simplified. (S.T.)

  1. Formulation Optimization of Freeze-Dried Long-Circulating Liposomes and In-Line Monitoring of the Freeze-Drying Process Using an NIR Spectroscopy Tool.

    Science.gov (United States)

    Sylvester, Bianca; Porfire, Alina; Van Bockstal, Pieter-Jan; Porav, Sebastian; Achim, Marcela; Beer, Thomas De; Tomuţă, Ioan

    2018-01-01

    The effect of lyoprotectant type and concentration on the stability of freeze-dried prednisolone sodium phosphate-loaded long-circulating liposomes was investigated. Trehalose at a 5:1 carbohydrate to lipid molar ratio proved to be superior in maintaining the structural integrity and the permeability properties of the liposome bilayers, assuring the desired characteristics of the final product: a cake with a porous structure and easy to reconstitute, a similar size to the liposomes before freeze-drying, a high percent of encapsulated drug, and a low residual moisture content. Further on, the study demonstrated the possibility of near-infrared spectroscopy to provide valuable insights for detecting critical changes in acyl chain packing of the liposome bilayer. By visualizing the spectra after principal component analysis, one can predict if any harm has occurred to liposome integrity during the process. Moreover, near-infrared spectroscopy enabled us to determine the end points of primary and secondary drying without disturbing the normal freeze-drying procedure, which allowed us to gain a better understanding of the process and to improve process efficiency by optimizing the primary and secondary drying time. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  2. Comparison of three-dimensional printing and vacuum freeze-dried techniques for fabricating composite scaffolds

    International Nuclear Information System (INIS)

    Sun, Kai; Li, Ruixin; Jiang, Wenxue; Sun, Yufu; Li, Hui

    2016-01-01

    In this study, the performances of different preparation methods of the scaffolds were analyzed for chondrocyte tissue engineering. Silk fibroin/collagen (SF/C) was fabricated using a vacuum freeze-dried technique and by 3D printing. The porosity, water absorption expansion rates, mechanical properties, and pore sizes of the resulting materials were evaluated. The proliferation and metabolism of the cells was detected at different time points using an MTT assay. Cell morphologies and distributions were observed by histological analysis and scanning electron microscopy (SEM). The porosity, water absorption expansion rate, and Young’s modulus of the material obtained via 3D printing were significantly higher than those obtained by the freeze-dried method, while the pore size did not differ significantly between the two methods. MTT assay results showed that the metabolism of cells seeded on the 3D printed scaffolds was more viable than the metabolism on the freeze-dried material. H&E staining of the scaffolds revealed that the number of cells in the 3D printed scaffold was higher in comparison to a similar measurement on the freeze-dried material. Consequently, stem cells grew well inside the 3D printed scaffolds, as measured by SEM, while the internal structure of the freeze-dried scaffold was disordered. Compared with the freeze-dried technique, the 3D printed scaffold exhibited better overall performance and was more suitable for cartilage tissue engineering. - Highlights: • Silk fibroin/collagen was fabricated using 3D printing. • Physical characterization and Cell compatibility were compared. • 3D printed scaffold exhibited better overall performance.

  3. Comparison of three-dimensional printing and vacuum freeze-dried techniques for fabricating composite scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Kai [Tianjin First Center Hospital, No. 24 Fukang Road, Tianjin, TJ 300192 (China); Li, Ruixin [Institute of Medical Equipment, Academy of Military and Medical Sciences, No. 106, Wandong Street, Hedong District, Tianjin 300000 (China); Jiang, Wenxue, E-mail: jiangortholivea@sina.cn [Tianjin First Center Hospital, No. 24 Fukang Road, Tianjin, TJ 300192 (China); Sun, Yufu [Tianjin First Center Hospital, No. 24 Fukang Road, Tianjin, TJ 300192 (China); Li, Hui [Tianjin Medical University General Hospital, No. 154 Anshan Road, Tianjin, TJ 300052 (China)

    2016-09-02

    In this study, the performances of different preparation methods of the scaffolds were analyzed for chondrocyte tissue engineering. Silk fibroin/collagen (SF/C) was fabricated using a vacuum freeze-dried technique and by 3D printing. The porosity, water absorption expansion rates, mechanical properties, and pore sizes of the resulting materials were evaluated. The proliferation and metabolism of the cells was detected at different time points using an MTT assay. Cell morphologies and distributions were observed by histological analysis and scanning electron microscopy (SEM). The porosity, water absorption expansion rate, and Young’s modulus of the material obtained via 3D printing were significantly higher than those obtained by the freeze-dried method, while the pore size did not differ significantly between the two methods. MTT assay results showed that the metabolism of cells seeded on the 3D printed scaffolds was more viable than the metabolism on the freeze-dried material. H&E staining of the scaffolds revealed that the number of cells in the 3D printed scaffold was higher in comparison to a similar measurement on the freeze-dried material. Consequently, stem cells grew well inside the 3D printed scaffolds, as measured by SEM, while the internal structure of the freeze-dried scaffold was disordered. Compared with the freeze-dried technique, the 3D printed scaffold exhibited better overall performance and was more suitable for cartilage tissue engineering. - Highlights: • Silk fibroin/collagen was fabricated using 3D printing. • Physical characterization and Cell compatibility were compared. • 3D printed scaffold exhibited better overall performance.

  4. Effect of gamma irradiation on the qualitative characteristics of freeze dried forest fruits

    International Nuclear Information System (INIS)

    Nacheva, I; Miteva, P.; Metodieva, P.; Todorova, Ya.; Loginovska, K.

    2012-01-01

    The purpose of the present investigation was to establish the effect of a combined technological processing - freeze drying and gamma sterilization - with irradiation doses of 2 and 4 kGy on the qualitative characteristics on a set of forest fruits - blackberry, blueberry, aronia, strawberry and black elder. The results prove that the freeze drying technology and the applied irradiation dose of 2 kGy is sufficient to preserve the quality and prolong the shelf life of the studied products without damage of their physical-chemical and microbiological characteristics

  5. Controlled ice nucleation in the field of freeze-drying: fundamentals and technology review.

    Science.gov (United States)

    Geidobler, R; Winter, G

    2013-10-01

    In the scientific community as well as in commercial freeze-drying, controlled ice nucleation has received a lot of attention because increasing the ice nucleation temperature can significantly reduce primary drying duration. Furthermore, controlled ice nucleation enables to reduce the randomness of the ice nucleation temperature, which can be a serious scale-up issue during process development. In this review, fundamentals of ice nucleation in the field of freeze-drying are presented. Furthermore, the impact of controlled ice nucleation on product qualities is discussed, and methods to achieve controlled ice nucleation are presented. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Freeze-drying process design by manometric temperature measurement: design of a smart freeze-dryer.

    Science.gov (United States)

    Tang, Xiaolin Charlie; Nail, Steven L; Pikal, Michael J

    2005-04-01

    To develop a procedure based on manometric temperature measurement (MTM) and an expert system for good practices in freeze drying that will allow development of an optimized freeze-drying process during a single laboratory freeze-drying experiment. Freeze drying was performed with a FTS Dura-Stop/Dura-Top freeze dryer with the manometric temperature measurement software installed. Five percent solutions of glycine, sucrose, or mannitol with 2 ml to 4 ml fill in 5 ml vials were used, with all vials loaded on one shelf. Details of freezing, optimization of chamber pressure, target product temperature, and some aspects of secondary drying are determined by the expert system algorithms. MTM measurements were used to select the optimum shelf temperature, to determine drying end points, and to evaluate residual moisture content in real-time. MTM measurements were made at 1 hour or half-hour intervals during primary drying and secondary drying, with a data collection frequency of 4 points per second. The improved MTM equations were fit to pressure-time data generated by the MTM procedure using Microcal Origin software to obtain product temperature and dry layer resistance. Using heat and mass transfer theory, the MTM results were used to evaluate mass and heat transfer rates and to estimate the shelf temperature required to maintain the target product temperature. MTM product dry layer resistance is accurate until about two-thirds of total primary drying time is over, and the MTM product temperature is normally accurate almost to the end of primary drying provided that effective thermal shielding is used in the freeze-drying process. The primary drying times can be accurately estimated from mass transfer rates calculated very early in the run, and we find the target product temperature can be achieved and maintained with only a few adjustments of shelf temperature. The freeze-dryer overload conditions can be estimated by calculation of heat/mass flow at the target product

  7. Improving survival and storage stability of bacteria recalcitrant to freeze-drying: a coordinated study by European culture collections.

    Science.gov (United States)

    Peiren, Jindrich; Buyse, Joke; De Vos, Paul; Lang, Elke; Clermont, Dominique; Hamon, Sylviane; Bégaud, Evelyne; Bizet, Chantal; Pascual, Javier; Ruvira, María A; Macián, M Carmen; Arahal, David R

    2015-04-01

    The objective of this study is to improve the viability after freeze-drying and during storage of delicate or recalcitrant strains safeguarded at biological resource centers. To achieve this objective, a joint experimental strategy was established among the different involved partner collections of the EMbaRC project ( www.embarc.eu ). Five bacterial strains considered as recalcitrant to freeze-drying were subjected to a standardized freeze-drying protocol and to seven agreed protocol variants. Viability of these strains was determined before and after freeze-drying (within 1 week, after 6 and 12 months, and after accelerated storage) for each of the protocols. Furthermore, strains were exchanged between partners to perform experiments with different freeze-dryer-dependent parameters. Of all tested variables, choice of the lyoprotectant had the biggest impact on viability after freeze-drying and during storage. For nearly all tested strains, skim milk as lyoprotectant resulted in lowest viability after freeze-drying and storage. On the other hand, best freeze-drying and storage conditions were strain and device dependent. For Aeromonas salmonicida CECT 894(T), best survival was obtained when horse serum supplemented with trehalose was used as lyoprotectant, while Aliivibrio fischeri LMG 4414(T) should be freeze-dried in skim milk supplemented with marine broth in a 1:1 ratio. Freeze-drying Campylobacter fetus CIP 53.96(T) using skim milk supplemented with trehalose as lyoprotectant resulted in best recovery. Xanthomonas fragariae DSM 3587(T) expressed high viability after freeze-drying and storage for all tested lyoprotectants and could not be considered as recalcitrant. In contrary, Flavobacterium columnare LMG 10406(T) did not survive the freeze-drying process under all tested conditions.

  8. Storage conditions affect oxidative stability and nutritional composition of freeze-dried Nannochloropsis salina

    DEFF Research Database (Denmark)

    Safafar, Hamed; Langvad, Sten; Møller, Peter

    2017-01-01

    composition of microalgae biomass. In order to investigate the worsening of the nutritional quality of freeze dried biomass, a multifactorial storage experiment was conducted on a high EPA (eicosapentaenoic acid) Nannochloropsis salina biomass. The storage time (0–56 days), storage temperature (5, 20,and 40...

  9. Protective Effect of Adonitol on Lactic Acid Bacteria Subjected to Freeze-Drying

    Science.gov (United States)

    de Valdéz, Graciela F.; de Giori, Graciela S.; de Ruiz Holgado, Aída A. P.; Oliver, Guillermo

    1983-01-01

    The protective effects of glycerol, adonitol, and four other related polyhydric alcohols on lactic acid bacteria subjected to freeze-drying were examined. The presence of adonitol in the suspending medium markedly protected the viabilities of the 12 stains tested. Dulcitol, mannitol, m-inositol, and sorbitol were found to provide little or no protection. PMID:6824318

  10. Response surface optimization of lyoprotectant for Lactobacillus bulgaricus during vacuum freeze-drying.

    Science.gov (United States)

    Chen, He; Chen, Shiwei; Li, Chuanna; Shu, Guowei

    2015-01-01

    The individual and interactive effects of skimmed milk powder, lactose, and sodium ascorbate on the number of viable cells and freeze-drying survival for vacuum freeze-dried powder formulation of Lactobacillus bulgaricus were studied by response surface methodology, and the optimal compound lyoprotectant formulations were gained. It is shown that skim milk powder, lactose, and sodium ascorbate had a significant impact on variables and survival of cultures after freeze-drying. Also, their protective abilities could be enhanced significantly when using them as a mixture of 28% w/v skim milk, 24% w/v lactose, and 4.8% w/v sodium ascorbate. The optimal freeze-drying survival rate and the number of viable cells of Lactobacillus bulgaricus were observed to be (64.41±0.02)% and (3.22±0.02)×10(11) colony-forming units (CFU)/g using the optimal compound protectants, which were very close to the expected values 64.47% and 3.28×10(11) CFU/g.

  11. Effect of buffer systems and disaccharides concentration on Podoviridae coliphage stability during freeze drying and storage.

    Science.gov (United States)

    Dini, C; de Urraza, P J

    2013-06-01

    The aims of this study were to determine the stability of Podoviridae coliphage CA933P during lyophilization and storage in different media, and to establish similarities between the results obtained and those expected through mechanisms described for proteins stabilization during freeze-drying. PBS and SM buffer were assayed as lyophilization media. The effect of inorganic salts concentration as well as the addition of disaccharides on phage stability during freeze-drying and storage was also studied. The addition of low sucrose concentration (0.1 mol l⁻¹) to SM buffer stabilized phage during freezing and drying steps of the lyophilization process, but higher sugar concentrations were detrimental to phage stability during freeze-drying. Sucrose stabilized phage during storage for at least 120 days. The lyoprotective effect of low concentrations of disaccharides during the drying step of the lyophilization of proteins as well as the stabilization of the freeze-dried product in time correlated with the results obtained for phage CA933P. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Optimization of Freeze Drying Conditions for Purified Pectinase from Mango (Mangifera indica cv. Chokanan) Peel

    Science.gov (United States)

    Mehrnoush, Amid; Mustafa, Shuhaimi; Yazid, Abdul Manap Mohd

    2012-01-01

    Response surface methodology (RSM) along with central composite design (CCD) was applied to optimize the freeze drying conditions for purified pectinase from mango (Mangifera indica cv. Chokanan) peel. The effect of pectinase content (−2.66, 62.66 mg/mL), Arabic gum (−1.21, 10.21%, w/v), and maltodextrin (0.73, 7.26%, w/v) as independent variables on activity, yield, and storage stability of freeze-dried enzyme was evaluated. Storage stability of pectinase was investigated after one week at 4 °C and yield percentage of the enzyme after encapsulation was also determined. The independent variables had the most significant (p < 0.05) effect on pectinase activity and yield of the enzyme. It was observed that the interaction effect of Arabic gum and maltodextrin improved the enzymatic properties of freeze-dried pectinase. The optimal conditions for freeze-dried pectinase from mango peel were obtained using 30 mg/mL of pectinase content, 4.5 (%, w/v) of Arabic gum, and 4 (%, w/v) of maltodextrin. Under these conditions, the maximum activity (11.12 U/mL), yield (86.4%) and storage stability (84.2%) of encapsulated pectinase were achieved. PMID:22489134

  13. Optimization of Freeze Drying Conditions for Purified Pectinase from Mango (Mangifera indica cv. Chokanan Peel

    Directory of Open Access Journals (Sweden)

    Abdul Manap Mohd Yazid

    2012-03-01

    Full Text Available Response surface methodology (RSM along with central composite design (CCD was applied to optimize the freeze drying conditions for purified pectinase from mango (Mangifera indica cv. Chokanan peel. The effect of pectinase content (−2.66, 62.66 mg/mL, Arabic gum (−1.21, 10.21%, w/v, and maltodextrin (0.73, 7.26%, w/v as independent variables on activity, yield, and storage stability of freeze-dried enzyme was evaluated. Storage stability of pectinase was investigated after one week at 4 °C and yield percentage of the enzyme after encapsulation was also determined. The independent variables had the most significant (p < 0.05 effect on pectinase activity and yield of the enzyme. It was observed that the interaction effect of Arabic gum and maltodextrin improved the enzymatic properties of freeze-dried pectinase. The optimal conditions for freeze-dried pectinase from mango peel were obtained using 30 mg/mL of pectinase content, 4.5 (%, w/v of Arabic gum, and 4 (%, w/v of maltodextrin. Under these conditions, the maximum activity (11.12 U/mL, yield (86.4% and storage stability (84.2% of encapsulated pectinase were achieved.

  14. Production of freeze-dried lactic acid bacteria starter culture for cassava fermentation into gari

    CSIR Research Space (South Africa)

    Yao, AA

    2009-10-01

    Full Text Available on the basis of their biochemical properties with a view to selecting appropriate starter cultures during cassava fermentation for gari production. In this study, the potential of these pre-selected strains as suitable freeze-dried cultures was evaluated...

  15. Effect of microwave freeze drying on quality and energy supply in drying of barley grass.

    Science.gov (United States)

    Cao, Xiaohuang; Zhang, Min; Mujumdar, Arun S; Zhong, Qifeng; Wang, Zhushang

    2018-03-01

    Young barley grass leaves are well-known for containing the antioxidant substances flavonoid and chlorophyll. However, low product quality and energy efficiency exist with respect to the dehydration of barley grass leaves. To improve energy supply and the quality of barley grass, microwave heating instead of contact heat was applied for the freeze drying of barley grass at a pilot scale at 1, 1.5 and 2 W g -1 , respectively; After drying, energy supply and quality parameters of color, moisture content, chlorophyll, flavonoids, odors of dried barley grass were determined to evaluate the feasibility of the study. Microwave freeze drying (MFD) allowed a low energy supply and high contents of chlorophyll and flavonoids. A lightness value of 60.0, a green value of -11.5 and an energy supply of 0.61 kW h -1  g -1 were observed in 1.5 W g -1 MFD; whereas drying time (7 h) decreased by 42% compared to contact heating. Maximum content of flavonoid and chlorophyll was 11.7 and 12.8 g kg -1 barley grass. Microwave heating leads to an odor change larger than that for contact heating observed for the freeze drying of barley grass. MFD retains chlorophyll and flavonoids, as well as colors and odors of samples, and also decreases energy consumption in the freeze drying of barley grass. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  16. Size and molecular flexibility of sugars determine the storage stability of freeze-dried proteins

    NARCIS (Netherlands)

    Tonnis, W. F.; Mensink, M. A.; de Jager, A.; Maarschalk, K. van der Voort; Frijlink, H. W.; Hinrichs, W. L. J.

    Protein-based biopharmaceuticals are generally produced as aqueous solutions and stored refrigerated to obtain sufficient shelf life. Alternatively, proteins may be freeze-dried in the presence of sugars to allow storage stability at ambient conditions for prolonged periods. However, to act as a

  17. Preparation of interconnected highly porous polymeric structures by a replication and freeze-drying process

    NARCIS (Netherlands)

    Hou, Q.; Grijpma, Dirk W.; Feijen, Jan

    2003-01-01

    Three-dimensional degradable porous polymeric structures with high porosities (93-98%) and well-interconnected pore networks have been prepared by freeze-drying polymer solutions in the presence of a leachable template followed by leaching of the template. Templates of the pore network were prepared

  18. Are freeze drying and oven drying methods for trace metal determination in zoological specimens analytically sound

    International Nuclear Information System (INIS)

    Fourie, H.O.; Peisach, M.

    1976-01-01

    High specific activity radio-isotopes of chromium, zinc and selenium were used to label these elements accumulated by the oyster Crassostrea gigas. The retention of the metabolised forms of these elements during freeze-drying or oven drying at 50, 90, 105 and 120 deg C was studied. Observed losses question the accuracy of these analytical procedures. (author)

  19. Fabrication of Li2TiO3 pebbles by a freeze drying process

    International Nuclear Information System (INIS)

    Lee, Sang-Jin; Park, Yi-Hyun; Yu, Min-Woo

    2013-01-01

    Li 2 TiO 3 pebbles were successfully fabricated by using a freeze drying process. The Li 2 TiO 3 slurry was prepared using a commercial powder of particle size 0.5–1.5 μm and the pebble pre-form was prepared by dropping the slurry into liquid nitrogen through a syringe needle. The droplets were rapidly frozen, changing their morphology to spherical pebbles. The frozen pebbles were dried at −10 °C in vacuum. To make crack-free pebbles, some glycerin was employed in the slurry, and long drying time and a low vacuum condition were applied in the freeze drying process. In the process, the solid content in the slurry influenced the spheroidicity of the pebble green body. The dried pebbles were sintered at 1200 °C in an air atmosphere. The sintered pebbles showed almost 40% shrinkage. The sintered pebbles revealed a porous microstructure with a uniform pore distribution and the sintered pebbles were crushed under an average load of 50 N in a compressive strength test. In the present study, a freeze drying process for fabrication of spherical Li 2 TiO 3 pebbles is introduced. The processing parameters, such as solid content in the slurry and the conditions of freeze drying and sintering, are also examined

  20. Preparation and Characterization of Solid Dispersions of Artemether by Freeze-Dried Method

    Directory of Open Access Journals (Sweden)

    Muhammad Tayyab Ansari

    2015-01-01

    Full Text Available Solid dispersions of artemether and polyethylene glycol 6000 (PEG6000 were prepared in ratio 12 : 88 (group-1. Self-emulsified solid dispersions of artemether were prepared by using polyethylene glycol 6000, Cremophor-A25, olive oil, Transcutol, and hydroxypropyl methylcellulose (HPMC in ratio 12 : 75 : 5 : 4 : 2 : 2, respectively (group-2. In third group, only Cremophor-A25 was replaced with Poloxamer 188 compared to group-2. The solid dispersions and self-emulsified solid dispersions were prepared by physical and freeze dried methods, respectively. All samples were characterized by X-ray diffraction, attenuated total reflectance Fourier transform infrared spectroscopy, differential scanning calorimeter, scanning electron microscopy, and solubility, dissolution, and stability studies. X-ray diffraction pattern revealed artemether complete crystalline, whereas physical mixture and freeze-dried mixture of all three groups showed reduced peak intensities. In attenuated total reflectance Fourier transform infrared spectroscopy spectra, C–H stretching vibrations of artemether were masked in all prepared samples, while C–H stretching vibrations were representative of polyethylene glycol 6000, Cremophor-A25, and Poloxamer 188. Differential scanning calorimetry showed decreased melting endotherm and increased enthalpy change (ΔH in both physical mixture and freeze-dried mixtures of all groups. Scanning electron microscopy of freeze-dried mixtures of all samples showed glassy appearance, size reduction, and embedment, while their physical mixture showed size reduction and embedment of artemether by excipients. In group-1, solubility was improved up to 15 times, whereas group-2 showed up to 121 times increase but, in group-3, when Poloxamer 188 was used instead of Cremophor-A25, solubility of freeze-dried mixtures was increased up to 135 times. In fasted state simulated gastric fluid at pH 1.6, the dissolution of physical

  1. Spray freeze drying to produce a stable Delta(9)-tetrahydrocannabinol containing inulin-based solid dispersion powder suitable for inhalation

    NARCIS (Netherlands)

    van Drooge, Dirk-Jan; Hinrichs, Wouter L J; Dickhoff, Bastiaan H J; Elli, Marco N A; Visser, Marinella R; Zijlstra, Gerrit S; Frijlink, Henderik W

    2005-01-01

    The purpose of this study is to investigate whether spray freeze drying produces an inhalable solid dispersion powder in which Delta(9)-tetrahydrocannabinol (THC) is stabilised. Solutions of THC and inulin in a mixture of tertiary butanol (TBA) and water were spray freeze dried. Drug loads varied

  2. Near-Infrared Imaging for High-Throughput Screening of Moisture-Induced Changes in Freeze-Dried Formulations

    DEFF Research Database (Denmark)

    Trnka, Hjalte; Palou, Anna; Panouillot, Pierre Emanuel

    2014-01-01

    formulations were freeze-dried in well plates. Samples were imaged with a NIR hyperspectral camera after freeze-drying and upon storage. On the basis of Karl Fischer titration reference values, a univariate quantification model was constructed and used to visualize the distribution of water within freeze...

  3. Microbiological evaluation of anatomical organs submitted to glycerinization and freeze-drying techniques

    Directory of Open Access Journals (Sweden)

    Marianna Justo

    2016-06-01

    Full Text Available Alternatives conservation techniques are being requested with the proposal of formaldehyde substitution. Formaldehyde results in excessive anatomical specimens' weight and it can cause serious health problems to the manipulator, such as cancer. However, it provides an efficient germicide and fungicide action depending on concentration. The substitute techniques are glicerinization and freeze-drying which have advantages such as non-production of smells, lightness of the organs and dispenses the use of fixatives in conservation. As well as both intrinsic and extrinsic factors interfere in microbial growth, microbiological analyzes are essential to detect possible deteriorative microorganisms in organs and concluding effectively the technique used. Formalinized, glycerinated and freeze-drying organs were collected in three different times which were intercalated by two months, except formalinization that had one evaluation. The procedure required the use of sterilized swabs wetted in peptone water and molds measuring 5,0 cm x 10,0 cm positioned on two different piece's local resulting in 100 cm2 of area, to spread plate of total moulds, mesophiles (except in freeze-drying, psychrophilic (only in freeze-drying and Pseudomonas sp (except in formalinization. All the plates were counted and compared between each technique's evaluations by variance analyzes. Both alternatives techniques resulted in zero or in very low microbial quantity to cause health problems as well as it preserve pieces morphology. All values of all analyzes resulted below 1/ml, showing that glicerinization and freeze-drying techniques are so as efficient as formaldehyde. Keywords: Organs conservation, Anatomical techniques, Microbiology, Microbial growth

  4. Initial boost release of transforming growth factor-β3 and chondrogenesis by freeze-dried bioactive polymer scaffolds.

    Science.gov (United States)

    Krüger, Jan Philipp; Machens, Isabel; Lahner, Matthias; Endres, Michaela; Kaps, Christian

    2014-12-01

    In cartilage regeneration, bio-activated implants are used in stem and progenitor cell-based microfracture cartilage repair procedures. Our aim was to analyze the chondrogenic potential of freeze-dried resorbable polymer-based polyglycolic acid (PGA) scaffolds bio-activated with transforming growth factor-β3 (TGFB3) on human subchondral mesenchymal progenitor cells known from microfracture. Progenitor cells derived from femur heads were cultured in the presence of freeze-dried TGFB3 in high-density pellet culture and in freeze-dried TGFB3-PGA scaffolds for chondrogenic differentiation. Progenitor cell cultures in PGA scaffolds as well as pellet cultures with and without continuous application of TGFB3 served as controls. Release studies showed that freeze-dried TGFB3-PGA scaffolds facilitate a rapid, initial boost-like release of 71.5% of TGFB3 in the first 10 h. Gene expression analysis and histology showed induction of typical chondrogenic markers like type II collagen and formation of cartilaginous tissue in TGFB3-PGA scaffolds seeded with subchondral progenitor cells and in pellet cultures stimulated with freeze-dried TGFB3. Chondrogenic differentiation in freeze-dried TGFB3-PGA scaffolds was comparable to cultures receiving TGFB3 continuously, while non-stimulated controls did not show chondrogenesis during prolonged culture for 14 days. These results suggest that bio-activated, freeze-dried TGFB3-PGA scaffolds have chondrogenic potential and are a promising tool for stem cell-mediated cartilage regeneration.

  5. Freeze-dried polymer-coated quantum dots for perspective biomedical application

    Science.gov (United States)

    Goftman, Valentina V.; Gaynbuch, Anna V.; Panfilova, Elizaveta V.; Khlebtsov, Boris N.; Goryacheva, Irina Y.

    2015-03-01

    Freeze-drying as known as lyophilization has been considered as a possible technique to improve the long-term stability of colloidal luminescent quantum dots (QDs) for perspective biomedical application. The paper describes synthesis of biocompatible CdSe-based core/shell QDs and discusses their optical and physical properties before and after freezedrying. Importantly, the dried nanoparticles can be stored for a long time under usual conditions and then can easily be redisperse in water at a desired concentration without such hard manipulations as sonication or heating. In this work two PEG-amine derivatives were applied for QDs pegylation: monoamine Jeffamine M1000 and diamine JeffamineED-2003. The use of different Jeffamines allows us to obtain QDs with different length of PEG chains and different ζ-potential. The influence of polymer composition on optical properties of the nanocrystals and on their stability after freeze-drying was studied.

  6. Fuzzy Logic-based expert system for evaluating cake quality of freeze-dried formulations

    DEFF Research Database (Denmark)

    Trnka, Hjalte; Wu, Jian-Xiong; van de Weert, Marco

    2013-01-01

    critical visual features such as the degree of cake collapse, glassiness, and color uniformity. On the basis of the IA outputs, a fuzzy logic system for analysis of these freeze-dried cakes was constructed. After this development phase, the system was tested with a new screening well plate. The developed...... are needed. The aim of this study was to develop a fuzzy logic system based on image analysis (IA) for analyzing cake quality. Freeze-dried samples with different visual quality attributes were prepared in well plates. Imaging solutions together with image analytical routines were developed for extracting...... fuzzy logic-based system was found to give comparable quality scores with visual evaluation, making high-throughput classification of cake quality possible....

  7. Development of freeze-dried miyeokguk, Korean seaweed soup, as a space food sterilized by irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ju Yeon [Chonbuk National University, Jeonju (Korea, Republic of); Song, Beom Seok; Park, Jin Gyu; Cho, Won Jun; Kim, Jae Hun; Yoon Yo Han; Choi, Jong Il; Lee, Ju Woon [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2010-03-15

    This study was conducted to evaluate the microbial (Total aerobic count, Coliform, Coagulase positive Staphylococci, Salmonella, Yeast/Mold, Escherichia coli, Bacillus cereus), Hunter' color values (L*, a*, b*) and organoleptic quality of freeze-dried Miyeokguk, Korean seaweed soup in space food, Bacillus cereus was 1 log level while not detected in the sample irradiated at 10 kGy. Hunter's color values of the samples irradiated less than 10 kGy was not significantly different (p>0.05). The sensory evaluation result showed that the preference scores in all the sensory properties decreased when it was irradiated over 10 kGy, but sensory score of less than 10 kGy samples was similar in all terms. Therefore, it was considered that gamma irradiation at 10 kGy was enough to sterilize the freeze-dried Miyeokguk without deterioration of sensory quality.

  8. Development of freeze-dried miyeokguk, Korean seaweed soup, as a space food sterilized by irradiation

    International Nuclear Information System (INIS)

    Lee, Ju Yeon; Song, Beom Seok; Park, Jin Gyu; Cho, Won Jun; Kim, Jae Hun; Yoon Yo Han; Choi, Jong Il; Lee, Ju Woon

    2010-01-01

    This study was conducted to evaluate the microbial (Total aerobic count, Coliform, Coagulase positive Staphylococci, Salmonella, Yeast/Mold, Escherichia coli, Bacillus cereus), Hunter' color values (L*, a*, b*) and organoleptic quality of freeze-dried Miyeokguk, Korean seaweed soup in space food, Bacillus cereus was 1 log level while not detected in the sample irradiated at 10 kGy. Hunter's color values of the samples irradiated less than 10 kGy was not significantly different (p>0.05). The sensory evaluation result showed that the preference scores in all the sensory properties decreased when it was irradiated over 10 kGy, but sensory score of less than 10 kGy samples was similar in all terms. Therefore, it was considered that gamma irradiation at 10 kGy was enough to sterilize the freeze-dried Miyeokguk without deterioration of sensory quality

  9. Spray freeze-dried nanofibrillated cellulose aerogels with thermal superinsulating properties.

    Science.gov (United States)

    Jiménez-Saelices, Clara; Seantier, Bastien; Cathala, Bernard; Grohens, Yves

    2017-02-10

    Nanofibrillated cellulose (NFC) aerogels were prepared by spray freeze-drying (SFD). Their structural, mechanical and thermal insulation properties were compared to those of NFC aerogels prepared by conventional freeze-drying (CFD). The purpose of this investigation is to develop superinsulating bioaerogels by reducing their pore size. Severe reduction of the aerogel pore size and skeleton architecture were observed by SEM, aerogels prepared by SFD method show a fibril skeleton morphology, which defines a mesoporous structure. BET analyses confirm the appearance of a new organization structure with pores of nanometric sizes. As a consequence, the thermal insulation properties were significantly improved for SFD materials compared to CFD aerogel, reaching values of thermal conductivity as low as 0.018W/(mK). Moreover, NFC aerogels have a thermal conductivity below that of air in ambient conditions, making them one of the best cellulose based thermal superinsulating material. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Development of a freeze-drying process of waste-solution, 2

    International Nuclear Information System (INIS)

    Kondo, Isao; Kawasaki, Takeshi

    1988-01-01

    The waste solution treatment process in Plutonium Conversion Development Facility (PCDF) consists of Evaporation-Condensation and Neutrazation-Agglometation-Precipitation process, which produces the distillate as recovered acid at first step and separates Pu-U element from condenced solution at second step. This process needs many stages to get high decontamination efficiency and then the Evaporator is in very corrosive state because the nitric acid solution is heated over 100 degrees C to be evaporated. So, in PCDF, it was started the development of Freeze-Drying process to waste solution treatment. This process is suitable for a little quantity of the solution including nitric acid as produced in the Microwave Heating method. Moreover the process has high decontamination efficiency and has good performance of equipment. The result of the cold test of Freeze-Drying process with nitric acid is discribed in this paper. (author)

  11. Distribution of Vapor Pressure in the Vacuum Freeze-Drying Equipment

    Directory of Open Access Journals (Sweden)

    Shiwei Zhang

    2012-01-01

    Full Text Available In the big vacuum freeze-drying equipment, the drying rate of materials is uneven at different positions. This phenomenon can be explained by the uneven distribution of vapor pressure in chamber during the freeze-drying process. In this paper, a mathematical model is developed to describe the vapor flow in the passageways either between material plates and in the channel between plate groups. The distribution of vapor pressure along flow passageway is given. Two characteristic factors of passageways are defined to express the effects of structural and process parameters on vapor pressure distribution. The affecting factors and their actions are quantitatively discussed in detail. Two examples are calculated and analyzed. The analysis method and the conclusions are useful to estimate the difference of material drying rate at different parts in equipment and to direct the choice of structural and process parameters.

  12. Recovery and storage method for radioactive iodine by vacuum freeze-drying

    International Nuclear Information System (INIS)

    Otsuka, Katsuyuki; Ouchi, Hitoshi; Suzuki, Toru.

    1990-01-01

    After scrubbing off-gas formed in a re-processing process for spent nuclear fuels, scrubbing liquids after use are subjected, as they are or with addition of additives, to a precipitating treatment. Then, liquid wastes containing radioactive iodine was subjected to freeze-drying treatment by freeze-drying under vacuum to recover radioactive iodine as iodine compounds. Off-gas scrubbing is conducted by using a sodium hydroxide solution and copper or silver ions may be added as additives in the precipitating treatment. Recovered iodine compounds containing radioactive iodine are solidified, either directly or after formulating into a composition of naturally existing iodine-containing ores by means of high pressure pressing into ores. This can prevent radioactive iodine 1 29I of long half-decay time from diffusing into the circumference and store the radioactive iodine stably for a long period of time. (T.M.)

  13. Freeze dried bone allografts in dental and maxillofacial reconstructive surgery - experience in Malaysia

    International Nuclear Information System (INIS)

    Abd Rani Samsudin; Meor Zaidi Meor Kamal

    1999-01-01

    The utilisation of vascularised and free bone autografts remain the goal standard in maxillofacial reconstructive surgery in Malaysia, but the use of freeze dried bone allograft is still widely practiced in many centres with variable results. This study evaluate the effectiveness and clinical efficacy of using radiation sterilised freeze dried bone allografts in oral and maxillofacial reconstructive surgery. The bone grafts were prepared at the Malaysian National Tissue Bank. Seventy eight patients who had undergone oral and Maxillofacial surgical procedures with reconstruction using bone allografts were included in this study. 50 patients were male and 28 patients were female and their age ranged from 14 to 75 years. Forty two patients underwent enucleation of benign cystic lesions in the jaws, 15 patients underwent repair of orbital floor fractures, 6 patients of jaw fractures with partial loss of bone while 8 patients underwent augmentation of depressed cheek bone. Another 4 patients had partial resection of the mandible because of cancer and 3 patients had facial osteotomies. A follow up period of 12 months up to 4 years was carried out. The patients were assessed both clinically and radiologically throughout their follow up visits. Clinical assessment showed no evidence of rejection of the implanted freeze dried allografts. Bone allografts implanted as inlay grafts demonstrated a better clinical performance than onlay grafts and the poorest results were obtained following bridging bony defects in the jaws. Radiation sterilised freeze dried bone allografts produced at the Malaysian National Tissue Bank are bio-compatible, functional, and provide predictable results when applied to selected areas of the facial skeleton

  14. X-ray microanalysis of freeze-dried and frozen-hydrated cryosections

    International Nuclear Information System (INIS)

    Zierold, K.

    1988-01-01

    The elemental composition and the ultrastructure of biological cells were studied by scanning transmission electron microscopy (STEM) combined with energy dispersive X-ray microanalysis. The preparation technique involves cryofixation, cryoultramicrotomy, cryotransfer, and freeze-drying of samples. Freeze-dried cryosections 100-nm thick appeared to be appropriate for measuring the distribution of diffusible elements and water in different compartments of the cells. The lateral analytical resolution was less than 50 nm, depending on ice crystal damage and section thickness. The detection limit was in the range of 10 mmol/kg dry weight for all elements with an atomic number higher than 12; for sodium and magnesium the detection limits were about 30 and 20 mmol/kg dry weight, respectively. The darkfield intensity in STEM is linearly related to the mass thickness. Thus, it becomes possible to measure the water content in intracellular compartments by using the darkfield signal of the dry mass remaining after freeze-drying. By combining the X-ray microanalytical data expressed as dry weight concentrations with the measurements of the water content, physiologically more meaningful wet weight concentrations of elements were determined. In comparison to freeze-dried cryosections frozen-hydrated sections showed poor contrast and were very sensitive against radiation damage, resulting in mass loss. The high electron exposure required for recording X-ray spectra made reproducible microanalysis of ultrathin (about 100-nm thick) frozen-hydrated sections impossible. The mass loss could be reduced by carbon coating; however, the improvement achieved thus far is still insufficient for applications in X-ray microanalysis. Therefore, at present only bulk specimens or at least 1-micron thick sections can be used for X-ray microanalysis of frozen-hydrated biological samples

  15. Uncertainty analysis as essential step in the establishment of the dynamic Design Space of primary drying during freeze-drying

    DEFF Research Database (Denmark)

    Mortier, Severine Therese F. C.; Van Bockstal, Pieter-Jan; Corver, Jos

    2016-01-01

    Large molecules, such as biopharmaceuticals, are considered the key driver of growth for the pharmaceutical industry. Freeze-drying is the preferred way to stabilise these products when needed. However, it is an expensive, inefficient, time- and energy-consuming process. During freeze-drying...... for pharmaceutical freeze-drying. Traditionally, the chamber pressure and shelf temperature are kept constant during primary drying, leading to less optimal process conditions. In this paper it is demonstrated how a mechanistic model of the primary drying step gives the opportunity to determine the optimal dynamic...

  16. Developing a framework to model the primary drying step of a continuous freeze-drying process based on infrared radiation

    DEFF Research Database (Denmark)

    Van Bockstal, Pieter-Jan; Corver, Jos; Mortier, Séverine Thérèse F.C.

    2018-01-01

    The continuous freeze-drying concept based on spinning the vials during freezing and on non-contact energy transfer via infrared (IR) radiation during drying, improves process efficiency and product quality (uniformity) compared to conventional batch freeze-drying. Automated control of this process....... These results assist in the selection of proper materials which could serve as IR window in the continuous freeze-drying prototype. The modelling framework presented in this paper fits the model-based design approach used for the development of this prototype and shows the potential benefits of this design...

  17. Freeze Drying Improves the Shelf-Life of Conductive Polymer Modified Neural Electrodes

    Directory of Open Access Journals (Sweden)

    Himadri S. Mandal

    2015-08-01

    Full Text Available Coating microelectrodes with conductive polymer is widely recognized to decrease impedance and improve performance of implantable neural devices during recording and stimulation. A concern for wide-spread use of this approach is shelf-life, i.e., the electrochemical stability of the coated microelectrodes prior to use. In this work, we investigated the possibility of using the freeze-drying process in order to retain the native low impedance state and, thereby, improve the shelf-life of conductive polymer poly(3,4-ethylenedioxythiophene (PEDOT-PSS modified neural electrodes. Control PEDOT-PSS coated microelectrodes demonstrated a significant increase in impedance at 1 kHz after 41–50 days of room temperature storage. Based on equivalent circuit modeling derived from electrochemical impedance spectroscopy, this increase in impedance could be largely attributed to a decrease in the interfacial capacitance consistent with a collapse and closing of the porous structure of the polymeric coating. Time-dependent electrochemical impedance measurements revealed higher stability of the freeze-dried coated microelectrodes compared to the controls, such that impedance values after 41–50 days appeared to be indistinguishable from the initial levels. This suggests that freeze drying PEDOT-PSS coated microelectrodes correlates with enhanced electrochemical stability during shelf storage.

  18. Determination of the drying and rehydration kinetics of freeze dried kiwi ( Actinidia deliciosa) slices

    Science.gov (United States)

    Ergün, Kadriye; Çalışkan, Gülşah; Dirim, Safiye Nur

    2016-12-01

    The aim of this study was to determine the drying and rehydration kinetics of freeze dried kiwi slices. Well-known thin layer drying models (Lewis, Page, Modified Page I, Henderson and Pabis, Modified Henderson and Pabis, Logarithmic, Midilli, Modified Midilli, Two-term, Two-term Exponential, Modified Two-term Exponential, and Wang and Singh) were fitted to the experimental data. A nonlinear regression analysis was used to evaluate the parameters of the selected models using statistical software SPSS 16.0. For the freeze drying process of the kiwi slices, the highest R2 value (0.997), and the lowest RMSE (0.018) as well as the χ2 (0.0004) values were obtained from the Two-term Exponential model. The effective moisture diffusivity (Deff) of the freeze dried kiwi slices was calculated with the Fick's diffusion model as 7.302 × 10-10 m2/s. The rehydration behavior was determined using distilled water at different solid-liquid ratios at room temperature (18 ± 1 °C) using Peleg's model. The kinetics of the total soluble solid loss was also determined.

  19. Technological Development of Brewing in Domestic Refrigerator Using Freeze-Dried Raw Materials

    Directory of Open Access Journals (Sweden)

    Angelika-Ioanna Gialleli

    2017-01-01

    Full Text Available Development of a novel directly marketable beer brewed at low temperature in a domestic refrigerator combined with yeast immobilization technology is presented in this study. Separately, freeze-dried wort and immobilized cells of the cryotolerant yeast strain Saccharomyces cerevisiae AXAZ-1 on tubular cellulose were used in low-temperature fermentation (2, 5 and 7 °C. The positive eff ect of tubular cellulose during low-temperature brewing was examined, revealing that freeze-dried immobilized yeast cells on tubular cellulose signifi cantly reduced the fermentation rates in contrast to freeze-dried free cells, although they are recommended for home-made beer production. Immobilization also enhanced the yeast resistance at low-temperature fermentation, reducing the minimum brewing temperature value from 5 to 2 °C. In the case of high-quality beer production, the eff ect of temperature and initial sugar concentration on the fermentation kinetics were assessed. Sensory enrichment of the produced beer was confi rmed by the analysis of the fi nal products, revealing a low diacetyl concentration, together with improved polyphenol content, aroma profi le and clarity. The proposed process for beer production in a domestic refrigerator can easily be commercialized and applied by dissolving the content of two separate packages in tap water; one package containing dried wort and the other dried immobilized cells on tubular cellulose suspended in tap water.

  20. The gravimetric method for the determination of residual moisture in freeze-dried biological products.

    Science.gov (United States)

    May, J C; Wheeler, R M; Grim, E

    1989-06-01

    The gravimetric test for the determination of residual moisture in freeze-dried biological products performed in a humidity- and temperature-controlled room with the use of scrupulous gravimetric analytical technique can be used to accurately determine residual moisture in freeze-dried biological products such as antihemophilic factor (human) or honey bee venom allergenic extract. This method determines the first water of hydration of sodium tartrate dihydrate (7.93%) to within 1.3% of the calculated value with a relative standard deviation of 0.3% for 10 replicates. For this gravimetric procedure, freeze-dried samples containing from 1.12 to 4.4% residual moisture had relative standard deviations ranging from 3.6 to 9.1%. Samples containing less than 1.0% residual moisture by the gravimetric method such as intravenous immune globulin and antihemophilic factor (human) had relative standard deviations ranging from 16.7 to 47.0%. Relative standard deviations for residual moisture tests performed on comparable samples by the Karl Fischer and thermogravimetric methods showed similar variability.

  1. Application of plackett-burman design in screening freeze drying cryoprotectants for Lactobacillus bulgaricus

    Directory of Open Access Journals (Sweden)

    Guowei SHU

    2015-08-01

    Full Text Available Lactobacillus bulgaricus is the bacteria commonly used in probiotic dairy product, including yogurt and cheese. The bacteria may be stored for long periods of time if it is freeze-dried. The cryoprotectant mixture for L. bulgaricus was optimized during the process of freeze-drying using a Plackett-Burman design and the steepest ascent test. In our initial tests, the cell survival rate and the number of viable cells were associated with the type of cyroprotectant used. Therefore, our optimization protocol focused on increasing survival rate. Substances that previously had a protective effect during freeze-drying were investigated, for example: sucrose, lactose, skim milk powder, sodium bicarbonate, sodium glutamate, magnesium sulfate, sodium ascorbate, yeast extract, vitamin B2, and phosphate buffer. We determined that the optimum cryoprotectant composition for L. bulgaricus consists of 28.0 g/100 mL skim milk powder, 24.0 g/100 mL lactose and 4.8 g/100 mL sodium ascorbate. The optimized cryoprotectant provides a 63.25% cell survival rate.

  2. Effect of Glycerol, as Cryoprotectant in the Encapsulation and Freeze Drying of Microspheres Containing Probiotic Cells

    Directory of Open Access Journals (Sweden)

    Oana Lelia Pop

    2015-05-01

    Full Text Available It is reported that probiotics provide several health benefits as they help in maintaining a good balance and composition of intestinal flora, and increase the resistance against invasion of pathogens. Ensuring adequate dosages of probiotics at the time of consumption is a challenge, because several factors during processing and storage affect the viability of probiotic organisms. Major emphasis has been given to protect the microorganisms with the help of encapsulation technique, by addition of different protectants. In this study, probiotic cells (Bifidobacterium lactis 300B were entrapped in alginate/pullulan microspheres. In the encapsulation formula glycerol was used as cryoprotectant in the freeze drying process for long time storage. It was observed that the survival of Bifidobacterium lactis 300B when encapsulated without cryoprotectant was higher than the formula with glycerol in the fresh obtained microspheres. The addition of glycerol was in order to reduce the deep freezing and freeze drying damages. In the chosen formulations, glycerol did not proved protection for the entrapped probiotic cells in the freeze drying process, for which the use of glycerol as cryoprotectant for alginate/pullulan Bifidobacterium lactis 300B entrapment is not recommended.

  3. Drying of α-amylase by spray drying and freeze-drying - a comparative study

    Directory of Open Access Journals (Sweden)

    S. S. de Jesus

    2014-09-01

    Full Text Available This study is aimed at comparing two traditional methods of drying of enzymes and at verifying the efficiency of each one and their advantages and disadvantages. The experiments were performed with a laboratory spray dryer and freeze-dryer using α-amylase as the model enzyme. An experimental design in star revealed that spray drying is mainly influenced by the inlet air temperature and feed flow rate, which were considered to be the main factors influencing the enzymatic activity and water activity; the long period of material exposure to high temperatures causes a partial activity loss. In the experiments of freeze drying, three methods of freezing were used (freezer, acetone and dry ice, and liquid nitrogen and samples subsequently freeze-dried for times ranging between 0-24 hours. The product obtained from the two techniques showed high enzymatic activity and low water activity. For the drying of heat-resistant enzymes, in which the product to be obtained does not have high added value, spray drying may be more economically viable because, in the freeze drying process, the process time can be considered as a limiting factor when choosing a technique.

  4. Fuzzy Logic-based expert system for evaluating cake quality of freeze-dried formulations.

    Science.gov (United States)

    Trnka, Hjalte; Wu, Jian X; Van De Weert, Marco; Grohganz, Holger; Rantanen, Jukka

    2013-12-01

    Freeze-drying of peptide and protein-based pharmaceuticals is an increasingly important field of research. The diverse nature of these compounds, limited understanding of excipient functionality, and difficult-to-analyze quality attributes together with the increasing importance of the biosimilarity concept complicate the development phase of safe and cost-effective drug products. To streamline the development phase and to make high-throughput formulation screening possible, efficient solutions for analyzing critical quality attributes such as cake quality with minimal material consumption are needed. The aim of this study was to develop a fuzzy logic system based on image analysis (IA) for analyzing cake quality. Freeze-dried samples with different visual quality attributes were prepared in well plates. Imaging solutions together with image analytical routines were developed for extracting critical visual features such as the degree of cake collapse, glassiness, and color uniformity. On the basis of the IA outputs, a fuzzy logic system for analysis of these freeze-dried cakes was constructed. After this development phase, the system was tested with a new screening well plate. The developed fuzzy logic-based system was found to give comparable quality scores with visual evaluation, making high-throughput classification of cake quality possible. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association.

  5. The influence of freezing rates on bovine pericardium tissue Freeze-drying

    Directory of Open Access Journals (Sweden)

    Camila Figueiredo Borgognoni

    2009-12-01

    Full Text Available The bovine pericardium has been used as biomaterial in developing bioprostheses. Freeze-drying is a drying process that could be used for heart valve's preservation. The maintenance of the characteristics of the biomaterial is important for a good heart valve performance. This paper describes the initial step in the development of a bovine pericardium tissue freeze-drying to be used in heart valves. Freeze-drying involves three steps: freezing, primary drying and secondary drying. The freezing step influences the ice crystal size and, consequently, the primary and secondary drying stages. The aim of this work was to investigate the influence of freezing rates on the bovine pericardium tissue freeze-drying parameters. The glass transition temperature and the structural behaviour of the lyophilized tissues were determined as also primary and secondary drying time. The slow freezing with thermal treatment presented better results than the other freeze-drying protocols.O pericárdio bovino é um material utilizado na fabricação de biopróteses. A liofilização é um método de secagem que vem sendo estudado para a conservação de válvulas cardíacas. A preservação das características do biomaterial é de fundamental importância no bom funcionamento das válvulas. Este artigo é a primeira etapa do desenvolvimento do ciclo de liofilização do pericárdio bovino. Liofilização é o processo de secagem no qual a água é removida do material congelado por sublimação e desorção da água incongelável, sob pressão reduzida. O congelamento influencia o tamanho do cristal de gelo e, consequentemente, a secagem primária e secundária. O objetivo deste estudo foi verificar a influência das taxas de congelamento nos parâmetros de liofilização do pericárdio bovino. Determinou-se a temperatura de transição vítrea e o comportamento estrutural do pericárdio bovino liofilizado. Determinou-se o tempo da secagem primária e secundária. O

  6. Allogenic bone rods with freeze drying and gamma rays irradiation for treatment of fracture

    International Nuclear Information System (INIS)

    Zhou Zhenbin

    1999-01-01

    Opened reduction and internal fixation are the usual treatment of fracture, but both methods need a second operation for removal implants. The benefits of the bone rods are that they can avoid the removement of internal fixation and will be absorbed spontaneously. The bone rods are made of allogeneic compact bones with freeze-drying and gamma rays irradiation supplied by Shanxi Provincial Tissue Bank. The purpose of this study is to evaluate allograft reaction, the stability of the internal fixation, osteoinduction in the treatment of fracture using allogeneic bone rods with freeze drying and gamma rays irradiation. From May 1997 to May 1998, fourteen cases (male 12, female 2) of treatment were reviewed. The mean age was 37.3 (21-5 1). There were 3 medial malleolus fractures, 7 tibia and fibula fractures, 1 ulna and radius fracture, 1 lateral condyle of humerus fracture. The clinical results were satisfactory. Because the strength of the bone rods are weaker than that of screws, the bone rods are only indicated in the fixation of cancellous bones fracture and unloaded bone fracture. It can be used as a supplementary fixation of loaded bone. It is not indicated for fixation of comminuted fracture. More than two bone rods may be used in the fixation of fracture in order to get stability of the fracture and decrease stress between rods which will prevent the break of the bone rods. Allogeneic bone rods with freeze-drying and gamma rays irradiation can be used as implants of non-immunogenicity. There are no allograft reactions in all cases (including fever, leukocytosis, exudation or swelling in the wound). Although plenty of experimental studies have showed that freeze drying with gamma rays irradiation (below 50 KGy) would not destroy BMP of bone allograft, but there is no osteoinduction in our cases. The healing of a fracture and bridging external callus are similar as other operations. This new technique may have the following advantages compare with the screws: 1

  7. A comparative evaluation of freeze dried bone allograft and decalcified freeze dried bone allograft in the treatment of intrabony defects: A clinical and radiographic study

    Directory of Open Access Journals (Sweden)

    Rajat Gothi

    2015-01-01

    Full Text Available Background: Ideal graft material for regenerative procedures is autogenous bone graft but the major disadvantage with this graft is the need for a secondary surgical site to procure donor material and the frequent lack of intraoral donor site to obtain sufficient quantities of autogenous bone for multiple or deep osseous defects. Hence, to overcome these disadvantages, bone allografts were developed as an alternative source of graft material. Materials and Methods: In 10 patients with chronic periodontitis, 20 bilateral infrabony defects were treated with freeze dried bone allograft (FDBA-Group A and decalcified freeze dried bone allograft (DFDBA-Group B. Clinical and radiographic parameters were assessed preoperatively and at 3 months and 6 months postoperatively. Data thus obtained was subjected to statistical analysis. Results: Significant improvement in the reduction in probing depth and relative attachment level (RAL from the baseline to 3 months to baseline to 6 months in group A and group B, which was statistically significant but no statistically significant reduction was seen between 3 months and 6 months. On inter-group comparison, no significant differences were observed at all-time points. In adjunct to the probing depth and RAL, the radiographic area of the defect showed a similar trend in intra-group comparison and no significant difference was seen on inter-group comparison at all-time points. Conclusions: Within the limitations of the current study, it can be concluded that DFDBA did not show any improvement in the clinical and radiographic parameters in the treatment of the intrabony defects as compared to FDBA.

  8. Effect of Drying Medium on Residual Moisture Content and Viability of Freeze-Dried Lactic Acid Bacteria

    Science.gov (United States)

    de Valdez, Graciela F.; de Giori, Graciela S.; de Ruiz Holgado, Aida P.; Oliver, Guillermo

    1985-01-01

    The effect of various substances on the relationship between residual moisture content and the viability of freeze-dried lactic acid bacteria has been studied. Compounds such as polymers, which display considerable ability in displacing water, showed no protective action during freeze-drying. Adonitol, on the other hand, produced the smallest change in water content at various times during drying and allowed the highest rate of survival. PMID:16346728

  9. Survival of freeze-dried microcapsules of α-galactosidase producing probiotics in a soy bar matrix.

    Science.gov (United States)

    Chen, Mo; Mustapha, Azlin

    2012-05-01

    Soy oligosaccharides, mainly α-galactosides, are prevalently present in soy protein products, and can result in unfavorable digestive effects when consumed. The aim of this research was to investigate the efficiency of α-galactoside reduction by probiotic bacterial hydrolysis and if such bacteria could be maintained in a high number in a soy protein product in a microencapsulated and freeze-dried form. The probiotic bacterium, Lactobacillus acidophilus LA-2, when induced by raffinose, exhibited a high level of α-galactosidase activity at 5.0 U/mg. To preserve probiotics with high viability, cells were microencapsulated and freeze-dried. Optimization of microencapsulation presented that a combination of κ-carrageenan and inulin at a proportion of 1.9:0.1 (w:w) as capsule wall materials, significantly retained the viability of the probiotics through freeze-drying (P ≤ 0.05). Scanning electron microscopic images confirmed that the morphology of the microcapsules was well preserved after freeze-drying. Upon incorporation into soy protein bars, the freeze-dried microcapsules of L. acidophilus LA-2 remained in high numbers throughout 14 weeks of storage at 4 °C. Results of this work with the support of other studies on microencapsulation benefits indicate a promising use of freeze-dried α-galactosidase positive microencapsulated probiotics in a soy food. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Stability evaluation of freeze-dried Lactobacillus paracasei subsp. tolerance and Lactobacillus delbrueckii subsp. bulgaricus in oral capsules.

    Science.gov (United States)

    Jalali, M; Abedi, D; Varshosaz, J; Najjarzadeh, M; Mirlohi, M; Tavakoli, N

    2012-01-01

    Freeze-drying is a common preservation technology in the pharmaceutical industry. Various studies have investigated the effect of different cryoprotectants on probiotics during freeze-drying. However, information on the effect of cryoprotectants on the stability of some Lactobacillus strains during freeze-drying seems scarce. Therefore, the aim of the present study was to establish production methods for preparation of oral capsule probiotics containing Lactobacillus paracasei subsp. tolerance and Lactobacillus delbrueckii subsp. Bulgaricus. It was also of interest to examine the effect of various formulations of cryoprotectant media containing skim milk, trehalose and sodium ascorbate on the survival rate of probiotic bacteria during freeze-drying at various storage temperatures. Without any cryoprotectant, few numbers of microorganisms survived. However, microorganisms tested maintained higher viability after freeze-drying in media containing at least one of the cryoprotectants. Use of skim milk in water resulted in an increased viability after lyophilization. Media with a combination of trehalose and skim milk maintained a higher percentage of live microorganisms, up to 82%. In general, bacteria retained a higher number of viable cells in capsules containing freeze-dried bacteria with sodium ascorbate after three months of storage. After this period, a marked decline was observed in all samples stored at 23°C compared to those stored at 4°C. The maximum survival rate (about 72-76%) was observed with media containing 6% skim milk, 8% trehalose and 4% sodium ascorbate.

  11. Optimization of a protective medium for freeze-dried Pichia membranifaciens and application of this biocontrol agent on citrus fruit.

    Science.gov (United States)

    Niu, X; Deng, L; Zhou, Y; Wang, W; Yao, S; Zeng, K

    2016-07-01

    To optimize a protective medium for freeze-dried Pichia membranifaciens and to evaluate biocontrol efficacies of agents against blue and green mould and anthracnose in citrus fruit. Based on the screening assays of saccharides and antioxidants, response surface methodology was used to optimize sucrose, sodium glutamate and skim milk to improve viability of freeze-dried Pi. membranifaciens. Biocontrol assays were conducted between fresh and freeze-dried Pi. membranifaciens against Penicillium italicum, Penicillium digitatum and Colletotrichum gloeosporioides in citrus fruit. Solving the regression equation indicated that the optimal protective medium was 6·06% (w/v) sucrose combined with 3·40% (w/v) sodium glutamate and 5·43% (w/v) skim milk. Pi. membranifaciens freeze-dried in the optimal protective medium showed 76·80% viability, and retained biocontrol efficacy against Pe. italicum, Pe. digitatum and Co. gloeosporioides in citrus fruit. The optimal protective medium showed more effective protective properties than each of the three protectants used alone. The viability of freeze-dried Pi. membranifaciens finally reached 76·80%. Meanwhile, the biocontrol efficacies showed no significant difference between fresh and freeze-dried yeast against Pe. italicum, Pe. digitatum and Co. gloeosporioides in citrus fruit. The results showed the potential value of Pi. membranifaciens CICC 32259 for commercialization. © 2016 The Society for Applied Microbiology.

  12. Freeze drying reduces the extractability of organochlorine pesticides in fish muscle tissue by microwave-assisted method

    International Nuclear Information System (INIS)

    Zhang, Yanyan; Lin, Nan; Su, Shu; Shen, Guofeng; Chen, Yuanchen; Yang, Chunli; Li, Wei; Shen, Huizhong; Huang, Ye; Chen, Han; Wang, Xilong; Liu, Wenxin; Tao, Shu

    2014-01-01

    Samples of animal origin are usually dried before solvent extraction for analysis of organic contaminants. The freeze drying technique is preferred for hydrophobic organic compounds in practice. In this study, it was shown that the concentration of organochlorine pesticides (OCPs) extracted from fish muscle tissue significantly decreased after the samples were freeze dried. And the reason for this reduced extractability seemed to be the resistance of OCPs associated with freeze-dried muscle protein to solvent extraction. The extractability can be recovered by adding water prior to extraction. It suggests that the dietary exposure risk of OCPs from fish might be underestimated if freeze-dried samples are used. - Highlights: • Freeze drying significantly reduces extractability of OCPs in fish muscle sample. • It is the protein that causes the reduction in extractability of OCPs. • The extractability can be recovered by adding water before extraction. - Freeze drying significantly decreases the concentrations of OCPs extracted from fish muscle samples by microwave-assisted method

  13. Analysis of the moisture evaporation process during vacuum freeze-drying of koumiss and shubat

    Science.gov (United States)

    Shingisov, Azret Utebaevich; Alibekov, Ravshanbek Sultanbekovich

    2017-05-01

    The equation for the calculating of a moisture evaporation rate in the vacuum freeze-drying, wherein as a driving force instead of the generally accepted in the drying theory of Δt temperature difference, Δp pressure difference, Δc concentration difference, a difference of water activity in the product and the relative air humidity (a_{{w}} - \\varphi) is suggested. By using the proposed equation, the processes of vacuum freeze-drying of koumiss and shubat were analyzed, and it was found two drying periods: constant and falling. On the first drying period, a moisture evaporation rate of koumiss is j = 2.75 × 10-3 kg/(m2 h) and of shubat is j = 2.37 × 10-3 kg/(m2 h). On the second period, values decrease for koumiss from j = 2.65 × 10-3 kg/(m2 h) to j = 1.60 × 10-3 kg/(m2 h), and for shubat from j = 2.25 × 10-3 kg/(m2 h) to j = 1.62 × 10-3 kg/(m2 h). Specific humidity for koumiss is ueq = 0.61 kg/kg and for shubat is ueq = 0.58 kg/kg. The comparative analyze of the experimental data of the moisture evaporation rate versus the theoretical calculation shows that the approximation reliability is R2 = 0.99. Consequently, the proposed equation is useful for the analyzing a moisture evaporation rate during a vacuum freeze-drying of dairy products, including cultured milk foods.

  14. Optimization of the secondary drying step in freeze drying using TDLAS technology.

    Science.gov (United States)

    Schneid, Stefan C; Gieseler, Henning; Kessler, William J; Luthra, Suman A; Pikal, Michael J

    2011-03-01

    The secondary drying phase in freeze drying is mostly developed on a trial-and-error basis due to the lack of appropriate noninvasive process analyzers. This study describes for the first time the application of Tunable Diode Laser Absorption Spectroscopy, a spectroscopic and noninvasive sensor for monitoring secondary drying in laboratory-scale freeze drying with the overall purpose of targeting intermediate moisture contents in the product. Bovine serum albumin/sucrose mixtures were used as a model system to imitate high concentrated antibody formulations. First, the rate of water desorption during secondary drying at constant product temperatures (-22 °C, -10 °C, and 0 °C) was investigated for three different shelf temperatures. Residual moisture contents of sampled vials were determined by Karl Fischer titration. An equilibration step was implemented to ensure homogeneous distribution of moisture (within 1%) in all vials. The residual moisture revealed a linear relationship to the water desorption rate for different temperatures, allowing the evaluation of an anchor point from noninvasive flow rate measurements without removal of samples from the freeze dryer. The accuracy of mass flow integration from this anchor point was found to be about 0.5%. In a second step, the concept was successfully tested in a confirmation experiment. Here, good agreement was found for the initial moisture content (anchor point) and the subsequent monitoring and targeting of intermediate moisture contents. The present approach for monitoring secondary drying indicated great potential to find wider application in sterile operations on production scale in pharmaceutical freeze drying. © 2011 American Association of Pharmaceutical Scientists

  15. In-line multipoint near-infrared spectroscopy for moisture content quantification during freeze-drying.

    Science.gov (United States)

    Kauppinen, Ari; Toiviainen, Maunu; Korhonen, Ossi; Aaltonen, Jaakko; Järvinen, Kristiina; Paaso, Janne; Juuti, Mikko; Ketolainen, Jarkko

    2013-02-19

    During the past decade, near-infrared (NIR) spectroscopy has been applied for in-line moisture content quantification during a freeze-drying process. However, NIR has been used as a single-vial technique and thus is not representative of the entire batch. This has been considered as one of the main barriers for NIR spectroscopy becoming widely used in process analytical technology (PAT) for freeze-drying. Clearly it would be essential to monitor samples that reliably represent the whole batch. The present study evaluated multipoint NIR spectroscopy for in-line moisture content quantification during a freeze-drying process. Aqueous sucrose solutions were used as model formulations. NIR data was calibrated to predict the moisture content using partial least-squares (PLS) regression with Karl Fischer titration being used as a reference method. PLS calibrations resulted in root-mean-square error of prediction (RMSEP) values lower than 0.13%. Three noncontact, diffuse reflectance NIR probe heads were positioned on the freeze-dryer shelf to measure the moisture content in a noninvasive manner, through the side of the glass vials. The results showed that the detection of unequal sublimation rates within a freeze-dryer shelf was possible with the multipoint NIR system in use. Furthermore, in-line moisture content quantification was reliable especially toward the end of the process. These findings indicate that the use of multipoint NIR spectroscopy can achieve representative quantification of moisture content and hence a drying end point determination to a desired residual moisture level.

  16. Determination of end point of primary drying in freeze-drying process control.

    Science.gov (United States)

    Patel, Sajal M; Doen, Takayuki; Pikal, Michael J

    2010-03-01

    Freeze-drying is a relatively expensive process requiring long processing time, and hence one of the key objectives during freeze-drying process development is to minimize the primary drying time, which is the longest of the three steps in freeze-drying. However, increasing the shelf temperature into secondary drying before all of the ice is removed from the product will likely cause collapse or eutectic melt. Thus, from product quality as well as process economics standpoint, it is very critical to detect the end of primary drying. Experiments were conducted with 5% mannitol and 5% sucrose as model systems. The apparent end point of primary drying was determined by comparative pressure measurement (i.e., Pirani vs. MKS Baratron), dew point, Lyotrack (gas plasma spectroscopy), water concentration from tunable diode laser absorption spectroscopy, condenser pressure, pressure rise test (manometric temperature measurement or variations of this method), and product thermocouples. Vials were pulled out from the drying chamber using a sample thief during late primary and early secondary drying to determine percent residual moisture either gravimetrically or by Karl Fischer, and the cake structure was determined visually for melt-back, collapse, and retention of cake structure at the apparent end point of primary drying (i.e., onset, midpoint, and offset). By far, the Pirani is the best choice of the methods tested for evaluation of the end point of primary drying. Also, it is a batch technique, which is cheap, steam sterilizable, and easy to install without requiring any modification to the existing dryer.

  17. Freeze dried blood and development of an artificial diet for blood feeding arthropods

    International Nuclear Information System (INIS)

    DeLoach, J.R.; Spates, G.E.; Kapatsa, G.M.; Sheffield, C.L.; Kabayo, J.P.

    1990-01-01

    The goals of the research were to determine the biochemical differences between freeze dried bovine and porcine blood relative to their nutritional value to Glossina palpalis palpalis and Stomoxys calcitrans and to develop an artificial diet for mass rearing these flies. Freeze dried bovine and porcine blood were found to differ in their amino acid content; total dietary lipids did not significantly differ, but some notable exceptions were found in fatty acid content. Both sonication and addition of foetal bovine serum to freeze dried bovine blood improved its nutritional value for G. p. palpalis. A two component, semi-defined artificial diet was developed for G. p. palpalis and S. calcitrans. The College Station diet consisted of lipid contaminated bovine haemoglobin (BHb) and bovine serum albumin (BSA). To conduct dietary deletion tests, a process was developed for preparing large quantities of ultrapure lipid free bovine haemoglobin. S. calcitrans fed on lipid free BHb plus BSA had zero fecundity. Lipids were re-added to the protein diet in three forms: (1) lipid contaminated BHb, (2) pure erythrocyte ghosts, and (3) pure lipids. It was found that membrane lipid from the erythrocyte is required by S. calcitrans. A defined artificial diet consisting of lipid free BHb, BSA, sphingomyelin, phosphatidyl ethanolamine, phosphatidyl serine and cholesterol gave normal adult survival, as well as near normal fecundity and percentage egg hatch for S. calcitrans. Knowing the identity of the lipids, it is now possible to prepare dietary formulations to alleviate dependency on the blood proteins BHb and BSA. (author). 34 refs, 1 fig., 15 tabs

  18. A freeze-dried graphene counter electrode enhances the performance of dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Hung, Kai-Hsiang; Wang, Hong-Wen, E-mail: hongwen@cycu.edu.tw

    2014-01-01

    A flexible graphene/polyimide (PI) counter electrode without a fluorine-doped tin oxide (FTO) layer has been fabricated for dye-sensitized solar cell (DSSCs) applications. The flexible counter electrode consists of polyimide double-sided tape as a substrate beneath a graphene film acting as the conductive and catalytic layer. Chemically reduced graphene oxide (rGO) on the PI electrode (rGO-PI) shows comparable catalytic activity to that of the reference sputtered platinum/FTO counter electrodes (Sputter-Pt/FTO). A DSSC with a freeze-dried rGO-PI (FD-rGO-PI) counter electrode shows an overall conversion efficiency (η) of 5.45%, while that of the conventional Sputter-Pt/FTO electrode is 5.52%. The DSSC with a thermally dried rGO-PI (Gel-rGO-PI) counter electrode (not freeze-dried) exhibits a smooth morphology and much poorer performance (η = 1.61%). Field emission scanning electron microscopy, electrochemical impedance spectroscopy, and cyclic voltammetry measurements demonstrate that the FD-rGO-PI electrode possesses a porous structure, numerous edges, minimum charge-transfer resistance and a higher electrocatalytic activity toward the I{sub 3}{sup −}/I{sup −} redox couple than that of the Gel-rGO-PI electrode. The high electrocatalytic activity, facile preparation procedure, absence of FTO, and material flexibility render the FD-rGO-PI electrode an ideal alternative to conventional DSSC counter electrodes. - Highlights: • Highly rough and conductive graphene-based counter electrode is synthesized. • The characteristics of graphene surface by freeze drying are different. • The graphene counter electrode exhibits comparable performance to that of sputtered Pt one.

  19. Large scale synthesis of nanostructured zirconia-based compounds from freeze-dried precursors

    International Nuclear Information System (INIS)

    Gómez, A.; Villanueva, R.; Vie, D.; Murcia-Mascaros, S.; Martínez, E.; Beltrán, A.; Sapiña, F.; Vicent, M.; Sánchez, E.

    2013-01-01

    Nanocrystalline zirconia powders have been obtained at the multigram scale by thermal decomposition of precursors resulting from the freeze-drying of aqueous acetic solutions. This technique has equally made possible to synthesize a variety of nanostructured yttria or scandia doped zirconia compositions. SEM images, as well as the analysis of the XRD patterns, show the nanoparticulated character of those solids obtained at low temperature, with typical particle size in the 10–15 nm range when prepared at 673 K. The presence of the monoclinic, the tetragonal or both phases depends on the temperature of the thermal treatment, the doping concentration and the nature of the dopant. In addition, Rietveld refinement of the XRD profiles of selected samples allows detecting the coexistence of the tetragonal and the cubic phases for high doping concentration and high thermal treatment temperatures. Raman experiments suggest the presence of both phases also at relatively low treatment temperatures. - Graphical abstract: Zr 1−x A x O 2−x/2 (A=Y, Sc; 0≤x≤0.12) solid solutions have been prepared as nanostructured powders by thermal decomposition of precursors obtained by freeze-drying, and this synthetic procedure has been scaled up to the 100 g scale. Highlights: ► Zr 1−x A x O 2−x/2 (A=Y, Sc; 0≤x≤0.12) solid solutions have been prepared as nanostructured powders. ► The synthetic method involves the thermal decomposition of precursors obtained by freeze-drying. ► The temperature of the thermal treatment controls particle sizes. ► The preparation procedure has been scaled up to the 100 g scale. ► This method is appropriate for the large-scale industrial preparation of multimetallic systems.

  20. Protection of fish oil from oxidation by microencapsulation using freeze-drying techniques

    DEFF Research Database (Denmark)

    Heinzelmann, K.; Franke, K.; Jensen, Benny

    2000-01-01

    of fish oil with respect to oxidation, it has to be protected from oxygen and light. The investigations presented demonstrate the microencapsulation of fish oil using freeze-drying techniques. Emulsions containing 10% fish oil, 10% sodium caseinate, 10% carbohydrate and 70% water were frozen using......(N-3)-Polyunsaturated fatty acids (PUFAs) reduce the risk of coronary heart disease. Cold sea water plankton and plankton- consuming fish are known sources of (n-3)-PUFAs. Enriching normal food components with fish oil is a tool for increasing the intake of (n-3)-PUFAs. Due to the high sensitivity...

  1. Electrolysis of polluting wastes: I - Wastewater from a seasoning freeze-drying industry

    OpenAIRE

    Angelis, Dejanira F. de; Corso, Carlos R.; Bidoia, Ederio D.; Moraes, Peterson B.; Domingos, Roberto N.; Rocha-Filho, Romeu C.

    1998-01-01

    Wastewater from a seasoning freeze-drying industry was electrolysed to increase its biodegradability. Stainless-steel electrodes were used at 9.09 A/m², for up to 80 min. Conductivity, pH, biochemical (BOD) and chemical (COD) oxygen demands, Daphnia similis acute toxicity bioassays, and bacteria counting through the plate count agar method were determined after different times of electrolysis. The results (e.g. higher BOD and lower COD) showed that the biodegradability of the wastewater was s...

  2. Protection of fish oil from oxidation by microencapsulation using freeze-drying techniques

    DEFF Research Database (Denmark)

    Heinzelmann, K.; Franke, K.; Jensen, Benny

    2000-01-01

    of fish oil with respect to oxidation, it has to be protected from oxygen and light. The investigations presented demonstrate the microencapsulation of fish oil using freeze-drying techniques. Emulsions containing 10% fish oil, 10% sodium caseinate, 10% carbohydrate and 70% water were frozen using...... on the oxidative stability of dried microencapsulated fish oil. The shelf life of the produced samples was determined by measuring the development of volatile oxidation products vs. storage time. It could be shown that the addition of antioxidants to fish oil was necessary to produce dried microencapsulated fish...

  3. Microbial analysis and survey test of gamma-irradiated freeze-dried fruits for patient's food

    International Nuclear Information System (INIS)

    Park, Jae-Nam; Sung, Nak-Yun; Byun, Eui-Hong; Byun, Eui-Baek; Song, Beom-Seok; Kim, Jae-Hun; Lee, Kyung-A; Son, Eun-Joo; Lyu, Eun-Soon

    2015-01-01

    This study examined the microbiological and organoleptic qualities of gamma-irradiated freeze-dried apples, pears, strawberries, pineapples, and grapes, and evaluated the organoleptic acceptability of the sterilized freeze-dried fruits for hospitalized patients. The freeze-dried fruits were gamma-irradiated at 0, 1, 2, 3, 4, 5, 10, 12, and 15 kGy, and their quality was evaluated. Microorganisms were not detected in apples after 1 kGy, in strawberries and pears after 4 kGy, in pineapples after 5 kGy, and in grapes after 12 kGy of gamma irradiation. The overall acceptance score, of the irradiated freeze-dried fruits on a 7-point scale at the sterilization doses was 5.5, 4.2, 4.0, 4.1, and 5.1 points for apples, strawberries, pears, pineapples, and grapes, respectively. The sensory survey of the hospitalized cancer patients (N=102) resulted in scores of 3.8, 3.7, 3.9, 3.9, and 3.7 on a 5-point scale for the gamma-irradiated freeze-dried apples, strawberries, pears, pineapples, and grapes, respectively. The results suggest that freeze-dried fruits can be sterilized with a dose of 5 kGy, except for grapes, which require a dose of 12 kGy, and that the organoleptic quality of the fruits is acceptable to immuno-compromised patients. However, to clarify the microbiological quality and safety of freeze-dried fruits should be verified by plating for both aerobic and anaerobic microorganisms. - Highlights: • Dried fruits can be sterilized with a dose of 12 kGy. • Sensory survey of the hospitalized cancer patients (N=102). • Sensory quality of dried fruits is acceptable to cancer patients

  4. Improvement of fish freshness determination method by the application of amorphous freeze-dried enzymes.

    Science.gov (United States)

    Srirangsan, Paveena; Hamada-Sato, Naoko; Kawai, Kiyoshi; Watanabe, Manabu; Suzuki, Toru

    2010-12-08

    Alkaline phosphatase (ALP), nucleoside phosphorylase (NP), and xanthine oxidase (XOD) were used in a colorimetric method for evaluation of fish freshness based on the Ki value. Two enzyme mixtures, NP-XOD and ALP-NP-XOD, were prepared with a color developing agent, and stabilities of the enzymes were improved by freeze-drying with glass-forming additives, i.e., sucrose and sucrose-gelatin. As a result, a linear relationship was obtained between the Ki values determined by the developed colorimetric method and a conventional high-performance liquid chromatography with a high correlation coefficient of 0.997. All enzyme samples containing the additive(s) were amorphous, and higher enzymes activities were maintained compared to those freeze-dried without an additive. Sucrose-gelatin/enzyme mixtures showed higher glass transition temperature; consequently, the enzymes were better stabilized than the sucrose/enzyme formulations. Using the sucrose-gelatin/enzyme mixture, Ki values of fish meat could be accurately determined even after 6-month storage of the dried enzymes at 40 °C.

  5. Infrared thermography for monitoring of freeze-drying processes: instrumental developments and preliminary results.

    Science.gov (United States)

    Emteborg, Håkan; Zeleny, Reinhard; Charoud-Got, Jean; Martos, Gustavo; Lüddeke, Jörg; Schellin, Holger; Teipel, Katharina

    2014-07-01

    Coupling an infrared (IR) camera to a freeze dryer for on-line monitoring of freeze-drying cycles is described for the first time. Normally, product temperature is measured using a few invasive Pt-100 probes, resulting in poor spatial resolution. To overcome this, an IR camera was placed on a process-scale freeze dryer. Imaging took place every 120 s through a Germanium window comprising 30,000 measurement points obtained contact-free from -40 °C to 25 °C. Results are presented for an empty system, bulk drying of cheese slurry, and drying of 1 mL human serum in 150 vials. During freezing of the empty system, differences of more than 5 °C were measured on the shelf. Adding a tray to the empty system, a difference of more than 8 °C was observed. These temperature differences probably cause different ice structures affecting the drying speed during sublimation. A temperature difference of maximum 13 °C was observed in bulk mode during sublimation. When drying in vials, differences of more than 10 °C were observed. Gradually, the large temperature differences disappeared during secondary drying and products were transformed into uniformly dry cakes. The experimental data show that the IR camera is a highly versatile on-line monitoring tool for different kinds of freeze-drying processes. © 2014 European Union.

  6. Freeze-drying of HI-6-loaded recombinant human serum albumin nanoparticles for improved storage stability.

    Science.gov (United States)

    Dadparvar, Miriam; Wagner, Sylvia; Wien, Sascha; Worek, Franz; von Briesen, Hagen; Kreuter, Jörg

    2014-10-01

    Severe intoxications with organophosphates require the immediate administration of atropine in combination with acetyl cholinesterase (AChE) reactivators such as HI-6. Although this therapy regimen enables the treatment of peripheral symptoms, the blood-brain barrier (BBB) restricts the access of the hydrophilic antidotes to the central nervous system which could lead to a fatal respiratory arrest. Therefore, HI-6-loaded albumin nanoparticles were previously developed to enhance the transport across this barrier and were able to reactivate organophosphate-(OP)-inhibited AChE in an in vitro BBB model. Since HI-6 is known to be moisture-sensitive, the feasibility of freeze-drying of the HI-6-loaded nanoparticles was investigated in the present study using different cryo- and lyoprotectants at different concentrations. Trehalose and sucrose (3%, w/v)-containing formulations were superior to mannitol concerning the physicochemical parameters of the nanoparticles whereas trehalose-containing samples were subject of a prolonged storage stability study at temperatures between -20°C and +40°C for predetermined time intervals. Shelf-life computations of the freeze-dried HI-6 nanoparticle formulations revealed a shelf-life time of 18 months when stored at -20°C. The formulations' efficacy was proven in vitro by reactivation of OP-inhibited AChE after transport over a porcine brain capillary endothelial cell layer model. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Freeze-drying technology: A separation technique for liquid nuclear materials

    International Nuclear Information System (INIS)

    Musgrave, J.A.; Efurd, D.W.; Banar, J.C.

    1997-01-01

    Freeze-drying technology (FDT) has been around for several decades as a separation technology. Most commonly, FDT is associated with the processing of food, but the largest industrial-scale use of FDT is in the pharmaceutical industry. Through a Cooperative Research and Development Agreement (CRADA) with BOC Edwards Calumatic, we are demonstrating the feasibility of FDT as a waste minimization and pollution prevention technology. This is a novel and innovative application of FDT. In addition, we plan to demonstrate that the freeze-dried residue is an ideal feed material for ceramic stabilization of radioactive waste and excess fissile material. The objective of this work is to demonstrate the feasibility of FDT for the separation of complex radioactive and nonradioactive materials, including liquids, slurries, and sludges containing a wide variety of constituents in which the separation factors are >10 8 . This is the first application of FDT in which the condensate is of primary importance. Our focus is applying this technology to the elimination of radioactive liquid discharges from facilities at Los Alamos National Laboratory (LANL) and within the U.S. Department of Energy complex; however, successful demonstration will lead to nuclear industry-wide applications

  8. Experimental determination of the key heat transfer mechanisms in pharmaceutical freeze-drying.

    Science.gov (United States)

    Ganguly, Arnab; Nail, Steven L; Alexeenko, Alina

    2013-05-01

    The study is aimed at quantifying the relative contribution of key heat transfer modes in lyophilization. Measurements of vial heat transfer rates in a laboratory-scale freeze-dryer were performed using pure water, which was partially sublimed under various conditions. The separation distance between the shelf and the vial was systematically varied, and sublimation rates were determined gravimetrically. The heat transfer rates were observed to be independent of separation distance between the vial and the shelf and linearly dependent on pressure in the free molecular flow limit, realized at low pressures (120 mTorr), heat transfer rates were independent of pressure and inversely proportional to separation distance. Previous heat transfer studies in conventional freeze-drying cycles have attributed a dominant portion of the total heat transfer to radiation, the rest to conduction, whereas convection has been found to be insignificant. Although the measurements reported here confirm the significance of the radiative and gas conduction components, the convective component has been found to be comparable to the gas conduction contribution at pressures greater than 100 mTorr. The current investigation supports the conclusion that the convective component of the heat transfer cannot be ignored in typical laboratory-scale freeze-drying conditions. Copyright © 2013 Wiley Periodicals, Inc.

  9. Optimization of freeze drying conditions for purified pectinase from mango (Mangifera indica cv. Chokanan) peel.

    Science.gov (United States)

    Mehrnoush, Amid; Mustafa, Shuhaimi; Yazid, Abdul Manap Mohd

    2012-01-01

    Response surface methodology (RSM) along with central composite design (CCD) was applied to optimize the freeze drying conditions for purified pectinase from mango (Mangifera indica cv. Chokanan) peel. The effect of pectinase content (-2.66, 62.66 mg/mL), Arabic gum (-1.21, 10.21%, w/v), and maltodextrin (0.73, 7.26%, w/v) as independent variables on activity, yield, and storage stability of freeze-dried enzyme was evaluated. Storage stability of pectinase was investigated after one week at 4 °C and yield percentage of the enzyme after encapsulation was also determined. The independent variables had the most significant (p mango peel were obtained using 30 mg/mL of pectinase content, 4.5 (%, w/v) of Arabic gum, and 4 (%, w/v) of maltodextrin. Under these conditions, the maximum activity (11.12 U/mL), yield (86.4%) and storage stability (84.2%) of encapsulated pectinase were achieved.

  10. [Optimization of lyophilization procedures for freeze-drying of human red blood cells].

    Science.gov (United States)

    Chen, Lin-feng; Liu, Jing-han; Wang, De-qing; Ouyang, Xi-lin; Zhuang, Yuan; Che, Ji; Yu, Yang; Li, Hui

    2010-09-01

    To investigate the different parameters of the lyophilization procedures that affect the recovery of the rehydrated red blood cells (RBCs). Human RBCs loaded in tubes were cooled with 4 different modes and subjected to water bath at 25 degrees celsius;. The morphological changes of the RBCs were observed to assess the degree of vitrification, and the specimens were placed in the freeze-dryer with the temperature set up at 40, -50, -60, -70 and -80 degrees celsius;. The rates of temperature rise of the main and secondary drying in the lyophilization procedures were compared, and the water residue in the specimens was determined. The protectant did not show ice crystal in the course of freezing and thawing. No significant difference was found in the recovery rate of the rehydrated RBCs freeze-dried at the minimum temperature of -70 degrees celsius; and -80 degrees celsius; (P > 0.05). The E procedure resulted in the maximum recovery of the RBCs (83.14% ± 9.55%) and Hb (85.33% ± 11.42%), showing significant differences from the other groups(P < 0.01 or 0.05). The recovery of the RBCs showed a positive correlation to the water residue in the samples. Fast cooling in liquid nitrogen and shelf precooling at -70 degrees celsius; with a moderate rate of temperature rise in lyophylization and a start dry temperature close to the shelf equilibrium temperature produce optimal freeze-drying result of human RBCs.

  11. Energy transfer during freeze-drying in dual-chamber cartridges.

    Science.gov (United States)

    Korpus, Christoph; Haase, Thomas; Sönnichsen, Caren; Friess, Wolfgang

    2015-05-01

    Freeze-drying essentially requires knowledge about the heat and mass transfer characteristics to assure product quality. Whereas this understanding has been created for freeze-drying in vials, only limited information is available for state-of-the-art multiple compartment container systems such as dual-chamber cartridges (DCCs). Therefore, the aim of this study was to investigate the heat transfer characteristics of this novel container format. Sublimation tests were carried out using pure water at 60, 100, 150, and 200 mTorr chamber pressure at a shelf temperature of 0°C. Custom-made aluminum blocks were used as holder systems. Two heat transfer coefficients could be identified: the coefficient characterizing heat transfer between shelf and block, KAl , and between block and cartridge, KDCC . KAl was dependent on all three modes of heat transfer: contact conduction, gas conduction, and radiation. For KDCC , contact conduction was negligible. Radiation strongly influenced the overall energy transfer as it is the major mode of heat transfer for KDCC and contributes up to 44% to KAl . A third coefficient, Ktot , was defined as an overall heat transfer coefficient. This knowledge about heat transfer enables a purposeful development and control of optimized lyophilization processes for this novel container system. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  12. Evaluation of Heat Flux Measurement as a New Process Analytical Technology Monitoring Tool in Freeze Drying.

    Science.gov (United States)

    Vollrath, Ilona; Pauli, Victoria; Friess, Wolfgang; Freitag, Angelika; Hawe, Andrea; Winter, Gerhard

    2017-05-01

    This study investigates the suitability of heat flux measurement as a new technique for monitoring product temperature and critical end points during freeze drying. The heat flux sensor is tightly mounted on the shelf and measures non-invasively (no contact with the product) the heat transferred from shelf to vial. Heat flux data were compared to comparative pressure measurement, thermocouple readings, and Karl Fischer titration as current state of the art monitoring techniques. The whole freeze drying process including freezing (both by ramp freezing and controlled nucleation) and primary and secondary drying was considered. We found that direct measurement of the transferred heat enables more insights into thermodynamics of the freezing process. Furthermore, a vial heat transfer coefficient can be calculated from heat flux data, which ultimately provides a non-invasive method to monitor product temperature throughout primary drying. The end point of primary drying determined by heat flux measurements was in accordance with the one defined by thermocouples. During secondary drying, heat flux measurements could not indicate the progress of drying as monitoring the residual moisture content. In conclusion, heat flux measurements are a promising new non-invasive tool for lyophilization process monitoring and development using energy transfer as a control parameter. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  13. Effect of Controlled Ice Nucleation on Stability of Lactate Dehydrogenase During Freeze-Drying.

    Science.gov (United States)

    Fang, Rui; Tanaka, Kazunari; Mudhivarthi, Vamsi; Bogner, Robin H; Pikal, Michael J

    2018-03-01

    Several controlled ice nucleation techniques have been developed to increase the efficiency of the freeze-drying process as well as to improve the quality of pharmaceutical products. Owing to the reduction in ice surface area, these techniques have the potential to reduce the degradation of proteins labile during freezing. The objective of this study was to evaluate the effect of ice nucleation temperature on the in-process stability of lactate dehydrogenase (LDH). LDH in potassium phosphate buffer was nucleated at -4°C, -8°C, and -12°C using ControLyo™ or allowed to nucleate spontaneously. Both the enzymatic activity and tetramer recovery after freeze-thawing linearly correlated with product ice nucleation temperature (n = 24). Controlled nucleation also significantly improved batch homogeneity as reflected by reduced inter-vial variation in activity and tetramer recovery. With the correlation established in the laboratory, the degradation of protein in manufacturing arising from ice nucleation temperature differences can be quantitatively predicted. The results show that controlled nucleation reduced the degradation of LDH during the freezing process, but this does not necessarily translate to vastly superior stability during the entire freeze-drying process. The capability of improving batch homogeneity provides potential advantages in scaling-up from lab to manufacturing scale. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  14. Development of a freeze-dried fungal wettable powder preparation able to biodegrade chlorpyrifos on vegetables.

    Directory of Open Access Journals (Sweden)

    Jie Liu

    Full Text Available Continuous use of the pesticide chlorpyrifos has resulted in harmful contaminations in environment and species. Based on a chlorpyrifos-degrading fungus Cladosporium cladosporioides strain Hu-01 (collection number: CCTCC M 20711, a fungal wettable powder preparation was developed aiming to efficiently remove chlorpyrifos residues from vegetables. The formula was determined to be 11.0% of carboxymethyl cellulose-Na, 9.0% of polyethylene glycol 6000, 5.0% of primary alcohol ethoxylate, 2.5% of glycine, 5.0% of fucose, 27.5% of kaolin and 40% of freeze dried fungi by response surface methodology (RSM. The results of quality inspection indicated that the fungal preparation could reach manufacturing standards. Finally, the degradation of chlorpyrifos by this fungal preparation was determined on pre-harvest cabbage. Compared to the controls without fungal preparation, the degradation of chlorpyrifos on cabbages, which was sprayed with the fungal preparation, was up to 91% after 7 d. These results suggested this freeze-dried fungal wettable powder may possess potential for biodegradation of chlorpyrifos residues on vegetables and provide a potential strategy for food and environment safety against pesticide residues.

  15. Separation of nitrogen-krypton by the freeze-dried cellulose acetate membrane

    International Nuclear Information System (INIS)

    Tanioka, Akihiko; Ishikawa, Kinzo; Kakuta, Akio; Ozaki, Osamu; Oono, Masanori.

    1977-01-01

    The utility of freeze-dried cellulose acetate membranes, which consist of a thin skin layer supported upon a more porous matrix substructure, was examined for separation of nitrogen-radioactive krypton 85. The high permeable and separative membranes were prepared by fixed freezed-drying of swollen membrane after evaporation of acetone for 4-6 minutes. The permeation rate of nitrogen was 10 -1 -10 -3 (cc/cm 2 .sec.atm). Knudsen flow was predominant, since the permeation rate was inversely proportional to square root of molecular weight of gases. The influence of viscous flow was also observed by slight dependence on the pressure. The mean pore size was calculated by the equation of gas permeation in porous media. There exist fine pores of 30-40A radii in the skin layer. The separation factor (dilution of Kr) was about 0.7 and the separation efficiency was 60%. The collision between different gas molecules (Present-de Bethunes' effect) and the influence of viscous flow depreciates the efficiency. The separation efficiency which was determined by the experiment coincided with the one predicted according to the Present-de Bethunes' equation, supposing that the pore size in skin layer was 10-25A. (auth.)

  16. Production of grape juice powder obtained by freeze-drying after concentration by reverse osmosis

    Directory of Open Access Journals (Sweden)

    Poliana Deyse Gurak

    2013-12-01

    Full Text Available This study aimed to evaluate the freeze-drying process for obtaining grape juice powder by reverse osmosis using 50% grape juice pre-concentrated (28.5 °Brix and 50% hydrocolloids (37.5% maltodextrin and 12.5% arabic gum. The morphology of the glassy food showed the absence of crystalline structure, which was the amorphous wall that protected the contents of the powder. The samples were stored in clear and dark containers at room temperature, evaluated for their physical (X-ray diffraction for 65 days and chemical (polyphenol content stability for 120 days. During the storage time in plastic vessels, samples remained physically stable (amorphous and the phenolic concentration was constant, indicating the potentiality of this technique to obtain a stable product with a high concentration of phenolic compounds. Therefore, the freeze-drying process promoted the encapsulation of concentrated grape juice increasing its stability and shelf life, as well as proving to be an applicable process to food industry

  17. Microencapsulation of Natural Anthocyanin from Purple Rosella Calyces by Freeze Drying

    Science.gov (United States)

    Nafiunisa, A.; Aryanti, N.; Wardhani, D. H.; Kumoro, A. C.

    2017-11-01

    Anthocyanin extract in powder form will improve its use since the powder is easier to store and more applicable. Microencapsulation method is introduced as an efficient way for protecting pigment such as anthocyanin. This research was aimed to characterise anthocyanin encapsulated products prepared from purple Roselle calyces by freeze drying. The liquid anthocyanin extracts from ultrasound-assisted extraction were freeze-dried with and without the addition of 10% w/w maltodextrins as a carrier and coating agents. The quality attributes of the powders were characterised by their colour intensity, water content, and solubility. Analysis of encapsulated material was performed for the powder added by maltodextrin. The stability of the microencapsulated pigment in solution form was determined for 11 days. Total anthocyanin content was observed through pH differential method. The results of the colour intensity analysis confirm that the product with maltodextrin addition has more intense colour with L* value of 29.69 a* value of 54.29 and b* value of 8.39. The result with the addition of maltodextrin has less moisture content and more soluble in water. It is verified that better results were obtained for powder with maltodextrin addition. Anthocyanin in the powder form with maltodextrin addition exhibits higher stability even after 11 days. In conclusion, the microencapsulation of anthocyanin with maltodextrin as a carrier and coating agent presented a potential method to produce anthocyanin powder from purple Roselle.

  18. Drug nanoparticles by emulsion-freeze-drying via the employment of branched block copolymer nanoparticles.

    Science.gov (United States)

    Wais, Ulrike; Jackson, Alexander W; Zuo, Yanming; Xiang, Yu; He, Tao; Zhang, Haifei

    2016-01-28

    A large percentage of drug compounds exhibit low water solubility and hence low bioavailability and therapeutic efficacy. This may be addressed by preparation of drug nanoparticles, leading to enhanced dissolution rate and direct use for treatment. Various methods have been developed to produce drug nanocrystals, including wet milling, homogenization, solution precipitation, emulsion diffusion, and the recently developed emulsion freeze-drying. The drawback for these methods may include difficult control in particles size, use of surfactants & polymer, and low ratio of drug to stabilizer. Here, biocompatible branched block copolymer nanoparticles with lightly-crosslinked hydrophobic core and hydrophilic surface groups are synthesized by the direct monomer-to-particle methodology, characterized, and then used as scaffold polymer/surfactant to produce drug nanoparticles via the emulsion-freeze-drying approach. This method can be used for model organic dye and different poorly water-soluble drugs. Aqueous drug nanoparticle dispersions can be obtained with high ratio of drug to stabilizer and relatively uniform nanoparticle sizes. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Effects of ultrasonic pretreatments on quality, energy consumption and sterilization of barley grass in freeze drying.

    Science.gov (United States)

    Cao, Xiaohuang; Zhang, Min; Mujumdar, Arun S; Zhong, Qifeng; Wang, Zhushang

    2018-01-01

    Barley grass is a plant resource for rehabilitation therapy. Its processing requires retaining nutrition well for rehabilitation cure of consumers. To meet the aim as well as low energy consumption and microbiological safety of products, ultrasonic treatments (UT) were applied to bathing materials at different power levels (10, 30, 45, 60W/L) for 10mins. After treatments, the bathed barley grass (100g) was freeze-dried under vacuum -0.09MPa with fixed power of 2W/g. Parameters of color, microbial colony, energy consumption, glass transition temperature, moisture content, water activity, taste substances, contents of flavonoid and chlorophyll were determined after drying. In contrast with no treatment case, UT (45W/L) decreased drying time by 14% and decreased energy consumption by 19%; UT (60W/L) decreased total microbial colonies by 33%. Also, UT (30W/L) yielded contents of flavonoid (9.2/kg) and chlorophyll (10.5g/kg) of dried sample; UT power (10W/L) yielded the highest L ∗ (51.5) and the lowest a ∗ (-9.3) value. Simultaneously, UT leads to a higher glass transition temperature (Tg), lower water activity and produces less sourness and bitterness of dried products. Ultra-sonication is an alternative to improve quality, flavor and energy consumption of barley grass in freeze drying. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Demineralized Freeze-Dried Bovine Cortical Bone: Its Potential for Guided Bone Regeneration Membrane

    Directory of Open Access Journals (Sweden)

    David B. Kamadjaja

    2017-01-01

    Full Text Available Background. Bovine pericardium collagen membrane (BPCM had been widely used in guided bone regeneration (GBR whose manufacturing process usually required chemical cross-linking to prolong its biodegradation. However, cross-linking of collagen fibrils was associated with poorer tissue integration and delayed vascular invasion. Objective. This study evaluated the potential of bovine cortical bone collagen membrane for GBR by evaluating its antigenicity potential, cytotoxicity, immune and tissue response, and biodegradation behaviors. Material and Methods. Antigenicity potential of demineralized freeze-dried bovine cortical bone membrane (DFDBCBM was done with histology-based anticellularity evaluation, while cytotoxicity was analyzed using MTT Assay. Evaluation of immune response, tissue response, and biodegradation was done by randomly implanting DFDBCBM and BPCM in rat’s subcutaneous dorsum. Samples were collected at 2, 5, and 7 days and 7, 14, 21, and 28 days for biocompatibility and tissue response-biodegradation study, respectively. Result. DFDBCBM, histologically, showed no retained cells; however, it showed some level of in vitro cytotoxicity. In vivo study exhibited increased immune response to DFDBCBM in early healing phase; however, normal tissue response and degradation rate were observed up to 4 weeks after DFDBCBM implantation. Conclusion. Demineralized freeze-dried bovine cortical bone membrane showed potential for clinical application; however, it needs to be optimized in its biocompatibility to fulfill all requirements for GBR membrane.

  1. Development of freeze-dried DOTMP kits for labeling with {sup 68} Ga

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jae Cheong; Choi, Sang Mu; Cho, Eun Ha; Lee, So Young; Dho, So Hee; Kim, Soo Yong [Radioisotope Research Division, Dept. of Research Reactor Utilization, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Lyophilized dotMP kits were prepared using dotMP, ammonium acetate, and ascorbic acid. the {sup 68}Ga-dotMP was prepared by incubating the kit dissolved in 0.5 ml of concentrated {sup 68}Ga using nacl method and 0.5 ml of ddW, at 100 degrees C for 7 min. the labeling yield was evaluated by two solvent systems of tLc. 1 MBq of concentrated {sup 68}Ga was labeled with 0.8 μg of DOTMP by high radiolabeling yield (>98%), which was determined by two tLc methods. the composition of the prepared freeze-dried vial is 400 μg of DOTMP, 19.27 mg of ammonium acetate and 17.62 mg of ascorbic acid. ⁓555 MBq of {sup 68}Ga-dotMP was prepared with excellent radiochemical purity (>98%) and it was stable for 4 hr at room temperature. In conclusion, Freeze-dried dotMP kits for the convenient preparation of {sup 68}Ga-dotMP have been developed. Availability of this kit is expected to stimulate the widespread use of {sup 68}Ga-DOTMP in the fields of nuclear medicine.

  2. Freeze-drying of proteins in glass solids formed by basic amino acids and dicarboxylic acids.

    Science.gov (United States)

    Izutsu, Ken-ichi; Kadoya, Saori; Yomota, Chikako; Kawanishi, Toru; Yonemochi, Etsuo; Terada, Katsuhide

    2009-01-01

    The purpose of this study was to produce and characterize glass-state amorphous solids containing amino acids and organic acids that protect co-lyophilized proteins. Thermal analysis of frozen solutions containing a basic amino acid (e.g., L-arginine, L-lysine, L-histidine) and a hydroxy di- or tricarboxylic acid (e.g., citric acid, L-tartaric acid, DL-malic acid) showed glass transition of maximally freeze-concentrated solute at temperatures (T'g) significantly higher than those of the individual solute solutions. Mixing of the amino acid with some dicarboxylic acids (e.g., oxalic acid) also suggested an upward shift of the transition temperature. Contrarily, combinations of the amino acid with monocarboxylic acids (e.g., acetic acid) had T'gs between those of the individual solute solutions. Co-lyophilization of the basic amino acids and citric acid or L-tartaric acid resulted in amorphous solids that have glass transition temperatures (Tg) higher than the individual components. Mid- and near-infrared analysis indicated altered environment around the functional groups of the consisting molecules. Some of the glass-state excipient combinations protected an enzyme (lactate dehydrogenase, LDH) from inactivation during freeze-drying. The glass-state excipient combinations formed by hydrogen-bonding and electrostatic interaction network would be potent alternative to stabilize therapeutic proteins in freeze-dried formulations.

  3. Increasing the aperture of x-ray mosaic lenses by freeze drying

    International Nuclear Information System (INIS)

    Koch, F; Marschall, F; Meiser, J; Márkus, O; Faisal, A; Schröter, T; Meyer, P; Kunka, D; Last, A; Mohr, J

    2015-01-01

    Point focus x-ray mosaic lenses are limited in aperture by the aspect ratio that can be reached in the micro fabrication process. In lithography based micro fabrication processes, which are used to fabricate the lens pillar structures, the achievable aspect ratio is restricted by structure collapse due to capillary forces which occur during drying after development. Capillary forces can be avoided by freeze drying, hence avoiding the direct phase change from liquid to gas. Substituting conventional drying by freeze drying using cyclohexane at a temperature of  −10 °C, we could increase the achievable aspect ratio for the triangular pillar structures with edge length of 10 to 45 µm of the x-ray mosaic lenses by up to a factor of 2.2 with no further changes in process, material or structural geometry. A maximum aspect ratio of 30 was achieved for pillars with 10 µm edge length. The process can readily be employed to other structures or lithography techniques. (paper)

  4. Tert-butyl alcohol used to fabricate nano-cellulose aerogels via freeze-drying technology

    Science.gov (United States)

    Wang, Xiaoyu; Zhang, Yang; Jiang, Hua; Song, Yuxuan; Zhou, Zhaobing; Zhao, Hua

    2017-06-01

    Aerogel, a highly porous material, is attracting increasing attention owing to low thermal conductivity and high specific surface area. Freeze-drying technology has been employed to produce nano-cellulose aerogels; however, the resultant product has low specific surface areas. Here, a modified approach to prepare nano-cellulose aerogels was reported, which involves tert-butyl alcohol as a solvent. Nano-cellulose aerogels were prepared via a spontaneous gelation fashion using calcium chloride solution, followed by tert-butyl alcohol solvent displacement and freeze drying. Addition of calcium chloride (0.25%) accelerated the physical gelation process. The application of tert-butyl alcohol as a solvent contributed to preservation of gel network. The obtained spherical nano-cellulose aerogels had a shrinkage rate of 5.89%. The specific surface area and average pore size was 164. 9666 m2 g-1 and 10.01 nm, respectively. Additionally, nano-cellulose aerogels had a comparable thermal degradation property when compared to microcrystalline cellulose. These biophysical properties make nano-cellulose aerogels as a promising absorption material.

  5. Sedative and hypnotic effect of freeze-dried paeoniflorin and sini san freeze-dried powder in pentobarbital sodium-induced mice.

    Science.gov (United States)

    Li, Yuefeng; Wu, Pingan; Ning, Yanmei; Yan, Xingke; Zhu, Tiantian; Ma, Chongbing; Liu, Anguo

    2014-04-01

    To investigate the sedative and hypnotic activity of paeoniflorin and freeze-dried Sini San powder on mice and provide a reliable method for determining the pharmacodynamic material basis of Sini San. Male adult mice weighing 20-22 g were used in this study. Three experiments were carried out. Synergism with pentobarbital was used as an index for hypnotic effect. Loss of the righting reflex was used to determine the start of sleep. Sleep latency and sleeping time were recorded in each experiment. The coefficient of variation of the suprathreshold dose (55 mg/kg) was significantly lower than that of the threshold dose. The sleep latency of mice was significantly decreased, and the sleeping time of mice was significantly prolonged. The effects of paeoniflorin and Sini San on prolonging the sleeping time of mice induced by pentobarbital sodium were significantly stronger than those in the control group. Paeoniflorin produces significant sedative and hypnotic effects, and there is an obvious dose-effect relationship.

  6. Factors influencing the stability of freeze-dried stress-resilient and stress-sensitive strains of bifidobacteria.

    Science.gov (United States)

    Celik, O F; O'Sullivan, D J

    2013-06-01

    Freeze-drying is a common method for preservation of probiotics, including bifidobacteria, for further industrial applications. However, the stability of freeze-dried bifidobacteria varies depending on the freeze-drying method and subsequent storage conditions. The primary goals of this study were to develop an optimized freeze-drying procedure and to determine the effects of temperature, water activity, and atmosphere on survival of freeze-dried bifidobacteria. To address these goals, a commercially used bifidobacteria strain that is resilient to stress, Bifidobacterium animalis ssp. lactis Bb-12, and a characterized intestinal strain that is more sensitive to stress conditions, Bifidobacterium longum DJO10A, were used. A freeze-drying protocol was developed using trehalose as the cryoprotectant, which resulted in almost no loss of viability during freeze-drying. Resuscitation medium, temperature, and time did not significantly influence recovery rates when this cryoprotectant was used. The effects of temperature (-80 to 45°C), water activity (0.02 to 0.92), and atmosphere (air, vacuum, and nitrogen) were evaluated for the stability of the freeze-dried powders during storage. Freeze-dried B. animalis ssp. lactis Bb-12 was found to survive under all conditions tested, with optimum survival at temperatures up to 21°C, water activities up to 0.44, and all 3 atmospheres tested. The intestinal-adapted strain B. longum DJO10A was much more sensitive to the different storage conditions, but could be adequately maintained using optimum conditions. These optimum storage conditions included frozen storage, replacement of oxygen with nitrogen, and water activities between 0.11 and 0.22. These results indicated that an optimized storage environment is required to maintain viability of stress-sensitive bifidobacteria strains, whereas stress-resilient bifidobacteria strains can maintain viability over a wide range of storage conditions, which is practical in countries where

  7. Formulation Screening and Freeze-Drying Process Optimization of Ginkgolide B Lyophilized Powder for Injection.

    Science.gov (United States)

    Liu, Daichun; Galvanin, Federico; Yu, Ying

    2018-02-01

    The purpose of this study was to prepare ginkgolide B (GB) lyophilized powder for injection with excellent appearance and stable quality through a formulation screening and by optimizing the freeze-drying process. Cremophor EL as a solubilizer, PEG 400 as a latent solvent, and mannitol as an excipient were mixed to increase the solubility of GB in water to more than 18 times (about from 2.5 × 10 -4  mol/L (0.106 mg/mL) to 1.914 mg/mL). Formulation screening was conducted by orthogonal design where the content of GB in the solution before lyophilization (using external standard method of HPLC) and reconstitution time after lyophilization were the two evaluation indexes. The optimized formulations were GB in an amount of 2 mg/mL, Cremophor EL in an amount of 16% (v/v), PEG 400 in an amount of 9% (v/v), mannitol in an amount of 8% (w/v), and the solution pH of 6.5. Through four single-factor experiments (GB adding order, preparation temperature of GB solution, adding amount, and adsorption time of activated carbon), the preparation process of GB solution was confirmed. The glass transition temperature of maximally GB freeze-concentrated solution was - 17.6°C through the electric resistance method. GB lyophilized powder began to collapse at - 14.0°C, and the fully collapsed temperature was - 13.0°C, which were determined by freeze-drying microscope. When the collapse temperature was determined, the primary drying temperature was obtained. Thereby, the freeze-drying curve of GB lyophilized powder was initially identified. The freeze-drying process was optimized by orthogonal design, the qualified product appearance and residual moisture content were the two evaluation indexes. The optimized process parameters and process were (1) shelf temperature, decreased from room temperature to - 45.0°C, at 0.5°C/min in 2 h; (2) shelf temperature increased from - 45.0 to - 25.0°C, at 0.1°C/min, maintained for 3 h, and the chamber pressure was held at 10

  8. Effects of physical parameters on the heat and mass transfer characteristics in freeze-drying processes of fruits and vegetables

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Yuming; Liu, Lijuan; Liang, Li [Shanxi Agricultural Univ. (China). Coll. of Engineering and Technology], E-mail: guoyuming99@sina.com

    2008-07-01

    Studying the effects mechanism of material physical parameters on the heat and mass transfer characteristics, the process parameters and energy consumption during freeze-drying process is of importance in improving the vacuum freeze-drying process with low energy consumption. In this paper, the sliced and mashed carrots of one variety were selected to perform the vacuum freeze-drying experiments. First, the variation laws of surface temperatures and sublimation front temperatures of the two shapes samples during the freeze-drying processes were analyzed, and it was verified that the process of sliced carrots is controlled by mass transfer, while that of the mashed ones is heat-transfer control. Second, the variations of water loss rate, energy consumption and temperature of the two shapes samples under the appropriate heating plate temperature and the different drying chamber pressure were analyzed. In addition, the effects of thermal conductivity and thermal diffusivity on freeze-drying time and process parameters were discussed by utilizing the theory of heat and mass transfer. In conclusion, under the heat transfer condition, the temperature of the heating plate should be as high as possible within the permitted range, and the drying chamber pressure should be set at optimal level. While under the mass transport-limited condition, the pressure level need to be altered in short time. (author)

  9. Cell surface damage and morphological changes in Oenococcus oeni after freeze-drying and incubation in synthetic wine.

    Science.gov (United States)

    Bravo-Ferrada, Bárbara Mercedes; Gonçalves, Sónia; Semorile, Liliana; Santos, Nuno C; Brizuela, Natalia; Elizabeth Tymczyszyn, E; Hollmann, Axel

    2018-04-28

    The aim of the present study was to evaluate the effects of freeze-drying in the presence of trehalose as a cryoprotectant, followed by incubation in synthetic wine, on surface damage, viability and l-malic acid consumption of the oenological strain Oenococcus oeni UNQOe 73.2. After freeze-drying, no significant differences were observed in the number of viable cells (for both acclimated and non-acclimated cultures) respect to the fresh culture. In contrast, loss of viability was observed after wine incubation for 24 h, being acclimated freeze-dried cells the best conditions for this. After the preservation process, small changes in cell morphology were observed by Atomic Force Microscopy (AFM). The Zeta potential and AFM showed that 24 h of wine incubation was enough to induce several cell surface modifications. Plate count data allowed us to establish that surface damage is an important factor for loss of viability, regardless of the acclimation treatment. Although the number of surviving O. oeni cells decreased dramatically after incubation in synthetic wine for 15 days, the consumption of l-malic acid was higher than 70%, with freeze-dried cells showing a better performance than fresh cultures. These results demonstrate that O. oeni freeze-dried cultures could be applied to direct wine inoculation, to conduct malolactic fermentation, maintaining its technological properties and reducing the time and costs of the winemaking process. Copyright © 2018. Published by Elsevier Inc.

  10. Freeze-Drying as a Novel Biofabrication Method for Achieving a Controlled Microarchitecture within Large, Complex Natural Biomaterial Scaffolds.

    Science.gov (United States)

    Brougham, Claire M; Levingstone, Tanya J; Shen, Nian; Cooney, Gerard M; Jockenhoevel, Stefan; Flanagan, Thomas C; O'Brien, Fergal J

    2017-11-01

    The biofabrication of large natural biomaterial scaffolds into complex 3D shapes which have a controlled microarchitecture remains a major challenge. Freeze-drying (or lyophilization) is a technique used to generate scaffolds in planar 3D geometries. Here we report the development of a new biofabrication process to form a collagen-based scaffold into a large, complex geometry which has a large height to width ratio, and a controlled porous microarchitecture. This biofabrication process is validated through the successful development of a heart valve shaped scaffold, fabricated from a collagen-glycosaminoglycan co-polymer. Notably, despite the significant challenges in using freeze-drying to create such a structure, the resultant scaffold has a uniform, homogenous pore architecture throughout. This is achieved through optimization of the freeze-drying mold and the freezing parameters. We believe this to be the first demonstration of using freeze-drying to create a large, complex scaffold geometry with a controlled, porous architecture for natural biomaterials. This study validates the potential of using freeze-drying for development of organ-specific scaffold geometries for tissue engineering applications, which up until now might not have been considered feasible. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Effects of Freeze-Dried Vegetable Products on the Technological Process and the Quality of Dry Fermented Sausages.

    Science.gov (United States)

    Eisinaite, Viktorija; Vinauskiene, Rimante; Viskelis, Pranas; Leskauskaite, Daiva

    2016-09-01

    The aim of this study was to compare the chemical composition of freeze-dried vegetable powders: celery, celery juice, parsnip and leek. The effect of different freeze-dried vegetables onto the ripening process and the properties of dry fermented sausages was also evaluated. Vegetable products significantly (p sausages. In addition, the color parameters for sausages with the added lyophilised celery products were considerable (p sausages made with lyophilised celery juice were characterised by higher lightness and lower hardness than those made with the addition of other vegetable products and control. Freeze-dried celery, celery juice, parsnip and leek have some potential for the usage as a functional ingredient or as a source for indirect addition of nitrate in the production of fermented sausages. © 2016 Institute of Food Technologists®

  12. Suitability of microwave drying for mealworms (Tenebrio molitor) as alternative to freeze drying: Impact on nutritional quality and colour.

    Science.gov (United States)

    Lenaerts, S; Van Der Borght, M; Callens, A; Van Campenhout, L

    2018-07-15

    Freeze drying represents the current practice to stabilize mealworms, even though it is an energy demanding technique. Therefore, it was examined in the present study whether microwave drying could be a proper alternative. To this end, the impact of both drying techniques on the proximate composition, vitamin B 12 content, fatty acid profile, oxidation status and colour parameters of mealworms was investigated. Furthermore, the influence of the application of vacuum during microwave drying was studied. The different drying technologies resulted in small differences in the proximate composition, while the vitamin B 12 content was only reduced by microwave drying. The fat fraction of freeze dried mealworms showed a higher oxidation status than the fat of microwave dried mealworms. Application of a vacuum during the microwave drying process did not appear to offer advantages. This research shows that for mealworms microwave drying can be a proper alternative to freeze drying. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. The Production of a Stable Infliximab Powder: The Evaluation of Spray and Freeze-Drying for Production

    Science.gov (United States)

    Kanojia, Gaurav; Have, Rimko ten; Bakker, Arjen; Wagner, Koen; Frijlink, Henderik W.; Kersten, Gideon F. A.; Amorij, Jean-Pierre

    2016-01-01

    In prospect of developing an oral dosage form of Infliximab, for treatment of Crohn’s disease and rheumatoid arthritis, freeze-drying (vial vs Lyoguard trays) and spray-drying were investigated as production method for stable powders. Dextran and inulin were used in combination with sucrose as stabilizing excipients. The drying processes did not affect Infliximab in these formulations, i.e. both the physical integrity and biological activity (TNF binding) were retained. Accelerated stability studies (1 month at 60°C) showed that the TNF binding ability of Infliximab was conserved in the freeze-dried formulations, whereas the liquid counterpart lost all TNF binding. After thermal treatment, the dried formulations showed some chemical modification of the IgG in the dextran-sucrose formulation, probably due to Maillard reaction products. This study indicates that, with the appropriate formulation, both spray-drying and freeze-drying may be useful for (bulk) powder production of Infliximab. PMID:27706175

  14. Freeze-drying of HESylated IFNα-2b: Effect of HESylation on storage stability in comparison to PEGylation.

    Science.gov (United States)

    Liebner, Robert; Bergmann, Sarah; Hey, Thomas; Winter, Gerhard; Besheer, Ahmed

    2015-11-10

    A comparison of lyophilized PEGylated and HESylated IFNα was carried out to investigate the influence of protein conjugation, lyoprotectants as well as storage temperature on protein stability. Results show that PEG tends to crystallize during freeze-drying, reducing protein stability upon storage. In contrast, HESylation(®) drastically improved the stability over PEGylation by remaining totally amorphous during lyophilization, with and without lyoprotectants while providing a high glass transition temperature of the freeze-dried cakes. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Study of modified atmosphere packaging on the quality of ozonated freeze-dried chicken meat.

    Science.gov (United States)

    Zouaghi, Ferdaous; Cantalejo, María J

    2016-09-01

    The objective of this study was to evaluate the effects of different modified atmosphere packaging (MAP) conditions on the physicochemical and sensory properties of ozonated freeze-dried chicken meat stored at 21±1°C for 28days. To this end, 14 MAP treatments were performed to obtain the most suitable packaging atmosphere. High concentrations of O2 in MAP promoted loss of redness and increased the pH values. Moreover, when the concentration of CO2 in MAP was more than 40%, high values of textural parameters and low scores of sensory hardness and chewiness were achieved. The 20%CO2/80%N2 gas combination was found to be the most effective treatment for best maintaining the physicochemical and sensory quality of ozonated dried chicken samples similar to that of raw meat. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Freeze drying-assisted synthesis of Pt@reduced graphene oxide nanocomposites as excellent hydrogen sensor

    Science.gov (United States)

    Lu, Xiaojing; Song, Xinjie; Gu, Cuiping; Ren, Haibo; Sun, Yufeng; Huang, Jiarui

    2018-05-01

    Quick and efficient detection of low concentrations of hydrogen remains a challenge because of the stability of hydrogen. A sensor based on reduced oxide graphene functionalized with Pt nanoparticles is successfully fabricated using a freeze-drying method followed by heat treatment. The structure and morphology of the Pt@rGO nanocomposites are well analyzed by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The as-prepared Pt@rGO nanocomposites show excellent hydrogen gas sensing properties at a low working temperature of 50 °C. The sensitivity toward 0.5% hydrogen is 8%. The response and recovery times of the sensor exposed to 0.5% hydrogen are 63 and 104 s, respectively. The gas-sensing mechanism of Pt@rGO sensor is also discussed.

  17. Characteristics of Vacuum Freeze Drying with Utilization of Internal Cooling and Condenser Waste Heat for Sublimation

    Directory of Open Access Journals (Sweden)

    Muhammad Alhamid

    2013-09-01

    Full Text Available Vacuum freeze drying is an excellent drying method, but it is very energy-intensive because a relatively long drying time is required. This research investigates the utilization of condenser waste heat for sublimation as a way of accelerating the drying rate. In addition, it also investigates the effect of internal cooling combined with vacuum cooling in the pressure reduction process. Jelly fish tentacles were used as the specimen, with different configurations for condenser heat waste and internal cooling valve opening. The results show that heating with condenser heat waste can accelerate the drying rate up to 0.0035 kg/m2.s. In addition, pre-freezing by internal cooling prevents evaporation until the mass of the specimen is 0.47 g and promotes transition of the specimen into the solid phase.

  18. Physical characteristics of phycocyanin from spirulina microcapsules using different coating materials with freeze drying method

    Science.gov (United States)

    Dewi, E. N.; Purnamayati, L.; Kurniasih, R. A.

    2017-02-01

    The aim of this study was to compare the physical characteristics of phycocyanin microcapsules (F) from Spirulina sp. with different coating materials, such as κ-Carrageenan (C) and Na-alginate (A) in combination with maltodextrin (M) by freeze drying method. Microcapsules were prepared in three variations of coating materials i.e. maltodextrin (FM); maltodextrin and Na-alginate (FMA); and maltodextrin and carrageenan (FMC) with concentration of each materials were 10%; 9%:1.0%; and 9%:1% (w/w), respectively. The results showed that FMA with Na-alginate 1.0% produced the highest bulk density and total soluble solid, there were 0,334 g/ml and 9,067%, respectively. Color analysis by chromameter showed that FMC produced the bluest color compared to other samples. The glass transition temperature (Tg) investigated with Differential scanning calorimeter (DSC) in all of the samples.

  19. Large scale synthesis of nanostructured zirconia-based compounds from freeze-dried precursors

    Science.gov (United States)

    Gómez, A.; Villanueva, R.; Vie, D.; Murcia-Mascaros, S.; Martínez, E.; Beltrán, A.; Sapiña, F.; Vicent, M.; Sánchez, E.

    2013-01-01

    Nanocrystalline zirconia powders have been obtained at the multigram scale by thermal decomposition of precursors resulting from the freeze-drying of aqueous acetic solutions. This technique has equally made possible to synthesize a variety of nanostructured yttria or scandia doped zirconia compositions. SEM images, as well as the analysis of the XRD patterns, show the nanoparticulated character of those solids obtained at low temperature, with typical particle size in the 10-15 nm range when prepared at 673 K. The presence of the monoclinic, the tetragonal or both phases depends on the temperature of the thermal treatment, the doping concentration and the nature of the dopant. In addition, Rietveld refinement of the XRD profiles of selected samples allows detecting the coexistence of the tetragonal and the cubic phases for high doping concentration and high thermal treatment temperatures. Raman experiments suggest the presence of both phases also at relatively low treatment temperatures.

  20. Formation of highly porous aerosol particles by atmospheric freeze-drying in ice clouds.

    Science.gov (United States)

    Adler, Gabriela; Koop, Thomas; Haspel, Carynelisa; Taraniuk, Ilya; Moise, Tamar; Koren, Ilan; Heiblum, Reuven H; Rudich, Yinon

    2013-12-17

    The cycling of atmospheric aerosols through clouds can change their chemical and physical properties and thus modify how aerosols affect cloud microphysics and, subsequently, precipitation and climate. Current knowledge about aerosol processing by clouds is rather limited to chemical reactions within water droplets in warm low-altitude clouds. However, in cold high-altitude cirrus clouds and anvils of high convective clouds in the tropics and midlatitudes, humidified aerosols freeze to form ice, which upon exposure to subsaturation conditions with respect to ice can sublimate, leaving behind residual modified aerosols. This freeze-drying process can occur in various types of clouds. Here we simulate an atmospheric freeze-drying cycle of aerosols in laboratory experiments using proxies for atmospheric aerosols. We find that aerosols that contain organic material that undergo such a process can form highly porous aerosol particles with a larger diameter and a lower density than the initial homogeneous aerosol. We attribute this morphology change to phase separation upon freezing followed by a glass transition of the organic material that can preserve a porous structure after ice sublimation. A porous structure may explain the previously observed enhancement in ice nucleation efficiency of glassy organic particles. We find that highly porous aerosol particles scatter solar light less efficiently than nonporous aerosol particles. Using a combination of satellite and radiosonde data, we show that highly porous aerosol formation can readily occur in highly convective clouds, which are widespread in the tropics and midlatitudes. These observations may have implications for subsequent cloud formation cycles and aerosol albedo near cloud edges.

  1. Evaluation of 3D-Printed Polycaprolactone Scaffolds Coated with Freeze-Dried Platelet-Rich Plasma for Bone Regeneration

    Directory of Open Access Journals (Sweden)

    Junda Li

    2017-07-01

    Full Text Available Three-dimensional printing is one of the most promising techniques for the manufacturing of scaffolds for bone tissue engineering. However, a pure scaffold is limited by its biological properties. Platelet-rich plasma (PRP has been shown to have the potential to improve the osteogenic effect. In this study, we improved the biological properties of scaffolds by coating 3D-printed polycaprolactone (PCL scaffolds with freeze-dried and traditionally prepared PRP, and we evaluated these scaffolds through in vitro and in vivo experiments. In vitro, we evaluated the interaction between dental pulp stem cells (DPSCs and the scaffolds by measuring cell proliferation, alkaline phosphatase (ALP activity, and osteogenic differentiation. The results showed that freeze-dried PRP significantly enhanced ALP activity and the mRNA expression levels of osteogenic genes (ALP, RUNX2 (runt-related gene-2, OCN (osteocalcin, OPN (osteopontin of DPSCs (p < 0.05. In vivo, 5 mm calvarial defects were created, and the PRP-PCL scaffolds were implanted. The data showed that compared with traditional PRP-PCL scaffolds or bare PCL scaffolds, the freeze-dried PRP-PCL scaffolds induced significantly greater bone formation (p < 0.05. All these data suggest that coating 3D-printed PCL scaffolds with freeze-dried PRP can promote greater osteogenic differentiation of DPSCs and induce more bone formation, which may have great potential in future clinical applications.

  2. Optimization of a cryoprotective medium to increase the viability of freeze-dried Streptococcus thermophilus by response surface methodology

    Science.gov (United States)

    Streptococcus thermophilus normally exhibits different survival rates in different bacteria medium during freeze-drying. In this study, response surface methodology (RSM) was applied on the design of experiments for optimizing the cryoprotective medium. Results showed that the most significant facto...

  3. Impact of Microscale and Pilot-Scale Freeze-Drying on Protein Secondary Structures: Sucrose Formulations of Lysozyme and Catalase.

    Science.gov (United States)

    Peters, Björn-Hendrik; Leskinen, Jari T T; Molnár, Ferdinand; Ketolainen, Jarkko

    2015-11-01

    Microscale (MS) freeze-drying offers rapid process cycles for early-stage formulation development. The effects of the MS approach on the secondary structures of two model proteins, lysozyme and catalase, were compared with pilot-scale (PS) vial freeze-drying. The secondary structures were assessed by attenuated total reflection Fourier transformed infrared spectroscopy. Formulations were made with increasing sucrose-protein ratios. Freeze-drying protocols involved regular cooling without thermal treatment and annealing with MS and PS equipment, and cooling rate variations with the MS. Principal component analysis of smoothed second-derivative amide I spectra revealed sucrose-protein ratio-dependent shifts toward α-helical structures. Transferability of sucrose-protein formulations from MS to PS vial freeze-drying was evidenced at regular cooling rates. Local differences in protein secondary structures between the bottom and top of sucrose-catalase samples could be detected at the sucrose-catalase ratios of 1 and 2, this being related to the initial filling height and ice crystal morphology. Annealing revealed temperature, protein, formulation, and sample location-dependent effects influencing surface morphology at the top, or causing protein secondary structure perturbation at the bottom. With the MS approach, protein secondary structure differences at different cooling rates could be detected for sucrose-lysozyme samples at the sucrose-lysozyme ratio of 1. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  4. Effects of different rearing and feeding systems on lipid oxidation and antioxidant capacity of freeze-dried egg yolks.

    Science.gov (United States)

    Pignoli, Giovanni; Rodriguez-Estrada, Maria Teresa; Mandrioli, Mara; Barbanti, Lorenzo; Rizzi, Laura; Lercker, Giovanni

    2009-12-23

    Lipid oxidation and antioxidant capacity of freeze-dried egg yolks produced with two rearing systems (battery cages and free-range) and two types of feedings (conventional and organic) were studied. Nine fresh egg yolks of each crossed treatment were pooled, frozen for a month, freeze-dried, vacuum-packed, and kept at -18 degrees C until analysis. No significant differences were observed in the lipid (58.0-62.1%) and total sterol contents (33.0-35.5 g/kg of lipids) of the freeze-dried egg yolks. Free rearing and conventional feeding systems resulted in significantly higher total tocopherol, alpha-tocopherol, and lutein contents, as compared to the battery cage and the organic feed, respectively. However, no significant differences were found in lipid oxidation (peroxide value = 0.7-0.9 mequiv of O(2)/kg of fat; thiobarbituric reactive substances = 1.0-1.3 mg of malonylaldehyde/kg of sample) and cholesterol oxidation (28.8-43.5 mg of cholesterol oxidation products/kg of lipids; 0.08-0.12% oxidized cholesterol) of freeze-dried egg yolks except for 7alpha-hydroxycholesterol, which was significantly lower in samples obtained with organic feed.

  5. A comparison between spray drying and spray freeze drying to produce an influenza subunit vaccine powder for inhalation

    NARCIS (Netherlands)

    Saluja, V.; Amorij, J-P.; Kapteyn, J. C.; de Boer, A. H.; Frijlink, H. W.; Hinrichs, W. L. J.

    2010-01-01

    The aim of this study was to investigate two different processes to produce a stable influenza subunit vaccine powder for pulmonary immunization i.e. spray drying (SD) and spray freeze drying (SFD). The formulations were analyzed by proteolytic assay, single radial immunodiffusion assay (SRID),

  6. Fabrication of Li{sub 2}TiO{sub 3} pebbles by a freeze drying process

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang-Jin, E-mail: lee@mokpo.ac.kr [Department of Advanced Materials Science and Engineering, Mokpo National University, Muan 534-729 (Korea, Republic of); Park, Yi-Hyun [National Fusion Research Institute, Daejeon 305-806 (Korea, Republic of); Yu, Min-Woo [Department of Advanced Materials Science and Engineering, Mokpo National University, Muan 534-729 (Korea, Republic of)

    2013-11-15

    Li{sub 2}TiO{sub 3} pebbles were successfully fabricated by using a freeze drying process. The Li{sub 2}TiO{sub 3} slurry was prepared using a commercial powder of particle size 0.5–1.5 μm and the pebble pre-form was prepared by dropping the slurry into liquid nitrogen through a syringe needle. The droplets were rapidly frozen, changing their morphology to spherical pebbles. The frozen pebbles were dried at −10 °C in vacuum. To make crack-free pebbles, some glycerin was employed in the slurry, and long drying time and a low vacuum condition were applied in the freeze drying process. In the process, the solid content in the slurry influenced the spheroidicity of the pebble green body. The dried pebbles were sintered at 1200 °C in an air atmosphere. The sintered pebbles showed almost 40% shrinkage. The sintered pebbles revealed a porous microstructure with a uniform pore distribution and the sintered pebbles were crushed under an average load of 50 N in a compressive strength test. In the present study, a freeze drying process for fabrication of spherical Li{sub 2}TiO{sub 3} pebbles is introduced. The processing parameters, such as solid content in the slurry and the conditions of freeze drying and sintering, are also examined.

  7. The choice of a suitable oligosaccharide to prevent aggregation of PEGylated nanoparticles during freeze thawing and freeze drying

    NARCIS (Netherlands)

    Hinrichs, Wouter; Manceñido, F A; Sanders, N N; Braeckmans, K; De Smedt, S C; Demeester, J; Frijlink, H W

    2006-01-01

    In a previous Study we have shown that the oligosaccharide inulin can prevent aggregation of poly(ethylene glycol) (PEG) coated plasmid DNA/cationic liposome complexes ('' PEGylated lipoplexes '') during freeze thawing and freeze drying [Hinrichs et al., 2005. J. Control. Release 103, 465]. By

  8. Freeze-drying for controlled nanoparticle distribution in Co/SiO 2 Fischer–Tropsch catalysts

    NARCIS (Netherlands)

    Eggenhuisen, T.M.; Munnik, P.; Talsma, H.; de Jongh, P.E.; de Jong, K.P.

    2013-01-01

    Controlling the nanoparticle distribution over a support is considered essential to arrive at more stable catalysts. By developing a novel freeze drying method, the nanoparticle distribution was successfully manipulated for the preparation of Co/SiO2 Fischer-Tropsch catalysts using a commercial

  9. NIR spectroscopy for the in-line monitoring of a multicomponent formulation during the entire freeze-drying process

    NARCIS (Netherlands)

    Rosas, Juan G; de Waard, Hans; De Beer, Thomas; Vervaet, Chris; Remon, Jean Paul; Hinrichs, Wouter L J; Frijlink, Henderik W; Blanco, Marcel

    2014-01-01

    Freeze drying is a complex, time consuming and thus expensive process, hence creating a need for understanding the material behaviour in the process environment and for process optimization. Near-infrared (NIR) spectroscopy offers the opportunity to monitor physicochemical changes of the formulation

  10. Inulin sugar glasses preserve the structural integrity and biological activity of influenza virosomes during freeze-drying and storage

    NARCIS (Netherlands)

    de Jonge, Jørgen; Amorij, Jean-Pierre; Hinrichs, Wouter L.J.; Wilschut, Jan; Huckriede, Anke; Frijlink, Henderik W.

    Influenza virosomes are reconstituted influenza virus envelopes that may be used as vaccines or as carrier systems for cellular delivery of therapeutic molecules. Here we present a procedure to generate influenza virosomes as a stable dry-powder formulation by freeze-drying (lyophilization) using an

  11. Fibres as carriers for Lactobacillus rhamnosus during freeze-drying and storage in apple juice and chocolate-coated breakfast cereals.

    Science.gov (United States)

    Saarela, Maria; Virkajärvi, Ilkka; Nohynek, Liisa; Vaari, Anu; Mättö, Jaana

    2006-11-01

    The capability of different fibre preparations to protect the viability and stability of Lactobacillus rhamnosus during freeze-drying, storage in freeze-dried form and after formulation into apple juice and chocolate-coated breakfast cereals was studied. In freeze-drying trials wheat dextrin and polydextrose proved to be promising carriers for the L. rhamnosus strains: both freeze-drying survival and storage stability at 37 degrees C were comparable to the control carrier (sucrose). Using apple fibre and inulin carriers resulted in powders with fairly good initial freeze-drying survival but with poor storage stability at 37 degrees C. When fresh L. rhamnosus cells were added into apple juice (pH 3.5) together with oat flour with 20% beta-glucan the survival of the cells was much better at 4 degrees C and at 20 degrees C than with sucrose, wheat dextrin and polydextrose, whereas with freeze-dried cells no protective effect of oat flour could be seen. The stability of freeze-dried L. rhamnosus cells at 20 degrees C was higher in chocolate-coated breakfast cereals compared to low pH apple juice. Similar to freeze-drying stability, wheat dextrin and polydextrose proved to be better carriers than oat flour in chocolate-coated breakfast cereals. Regardless of their differing capability to adhere to fibre preparations the two L. rhamnosus strains studied gave parallel results in the stability studies with different carriers.

  12. Controlled Crystallization of the Lipophilic Drug Fenofibrate During Freeze-Drying : Elucidation of the Mechanism by In-Line Raman Spectroscopy

    NARCIS (Netherlands)

    de Waard, Hans; De Beer, Thomas; Hinrichs, Wouter L J; Vervaet, Chris; Remon, Jean-Paul; Frijlink, Henderik W

    2010-01-01

    We developed a novel process, "controlled crystallization during freeze-drying" to produce drug nanocrystals of poorly water-soluble drugs. This process involves freeze-drying at a relatively high temperature of a drug and a matrix material from a mixture of tertiary butyl alcohol and water,

  13. First steps towards tissue engineering of small-diameter blood vessels: preparation of flat scaffolds of collagen and elastin by means of freeze drying

    NARCIS (Netherlands)

    Buttafoco, L.; Engbers-Buijtenhuijs, P.; Poot, Andreas A.; Dijkstra, Pieter J.; Daamen, W.F.; van Kuppevelt, T.H.; Vermes, I.; Feijen, Jan

    2006-01-01

    Porous scaffolds composed of collagen or collagen and elastin were prepared by freeze drying at temperatures between -18 and -196°C. All scaffolds had a porosity of 90-98% and a homogeneous distribution of pores. Freeze drying at -18°C afforded collagen and collagen/elastin matrices with average

  14. State transitions and physicochemical aspects of cryoprotection and stabilization in freeze-drying of Lactobacillus rhamnosus GG (LGG).

    Science.gov (United States)

    Pehkonen, K S; Roos, Y H; Miao, S; Ross, R P; Stanton, C

    2008-06-01

    The frozen and dehydrated state transitions of lactose and trehalose were determined and studied as factors affecting the stability of probiotic bacteria to understand physicochemical aspects of protection against freezing and dehydration of probiotic cultures. Lactobacillus rhamnosus GG was frozen (-22 or -43 degrees C), freeze-dried and stored under controlled water vapour pressure (0%, 11%, 23% and 33% relative vapour pressure) conditions. Lactose, trehalose and their mixture (1 : 1) were used as protective media. These systems were confirmed to exhibit relatively similar state transition and water plasticization behaviour in freeze-concentrated and dehydrated states as determined by differential scanning calorimetry. Ice formation and dehydrated materials were studied using cold-stage microscopy and scanning electron microscopy. Trehalose and lactose-trehalose gave the most effective protection of cell viability as observed from colony forming units after freezing, dehydration and storage. Enhanced cell viability was observed when the freezing temperature was -43 degrees C. State transitions of protective media affect ice formation and cell viability in freeze-drying and storage. Formation of a maximally freeze-concentrated matrix with entrapped microbial cells is essential in freezing prior to freeze-drying. Freeze-drying must retain a solid amorphous state of protectant matrices. Freeze-dried matrices contain cells entrapped in the protective matrices in the freezing process. The retention of viability during storage seems to be controlled by water plasticization of the protectant matrix and possibly interactions of water with the dehydrated cells. Highest cell viability was obtained in glassy protective media. This study shows that physicochemical properties of protective media affect the stability of dehydrated cultures. Trehalose and lactose may be used in combination, which is particularly important for the stabilization of probiotic bacteria in dairy

  15. Stability of buffer-free freeze-dried formulations: A feasibility study of a monoclonal antibody at high protein concentrations.

    Science.gov (United States)

    Garidel, Patrick; Pevestorf, Benjamin; Bahrenburg, Sven

    2015-11-01

    We studied the stability of freeze-dried therapeutic protein formulations over a range of initial concentrations (from 40 to 160 mg/mL) and employed a variety of formulation strategies (including buffer-free freeze dried formulations, or BF-FDF). Highly concentrated, buffer-free liquid formulations of therapeutic monoclonal antibodies (mAbs) have been shown to be a viable alternative to conventionally buffered preparations. We considered whether it is feasible to use the buffer-free strategy in freeze-dried formulations, as an answer to some of the known drawbacks of conventional buffers. We therefore conducted an accelerated stability study (24 weeks at 40 °C) to assess the feasibility of stabilizing freeze-dried formulations without "classical" buffer components. Factors monitored included pH stability, protein integrity, and protein aggregation. Because the protein solutions are inherently self-buffering, and the system's buffer capacity scales with protein concentration, we included highly concentrated buffer-free freeze-dried formulations in the study. The tested formulations ranged from "fully formulated" (containing both conventional buffer and disaccharide stabilizers) to "buffer-free" (including formulations with only disaccharide lyoprotectant stabilizers) to "excipient-free" (with neither added buffers nor stabilizers). We evaluated the impacts of varying concentrations, buffering schemes, pHs, and lyoprotectant additives. At the end of 24 weeks, no change in pH was observed in any of the buffer-free formulations. Unbuffered formulations were found to have shorter reconstitution times and lower opalescence than buffered formulations. Protein stability was assessed by visual inspection, sub-visible particle analysis, protein monomer content, charge variants analysis, and hydrophobic interaction chromatography. All of these measures found the stability of buffer-free formulations that included a disaccharide stabilizer comparable to buffer

  16. Enhancing the aqueous solubility and dissolution of olanzapine using freeze-drying

    Directory of Open Access Journals (Sweden)

    Mudit Dixit

    2011-12-01

    Full Text Available The aim of the present study was to develop an olanzapine freeze-dried tablet (FDT. The solubility and dissolution rate of poorly water-soluble olanzapine was improved by preparing a freeze-dried tablet of olanzapine using the freeze-drying technique . The FDT was prepared by dispersing the drug in an aqueous solution of highly water-soluble carrier materials consisting of gelatin, glycine, and sorbitol. The mixture was poured in to the pockets of blister packs and then was subjected to freezing and lyophilisation. The FDT was characterised by DSC, XRD and SEM and was evaluated for saturation solubility and dissolution. The samples were stored in a stability chamber to investigate their physical stability. Results obtained by DSC and X-ray were analysed and showed the crystalline state of olanzapine in FDT transformation to the amorphous state during the formation of FDT. Scanning electron microscope (SEM results suggest reduction in olanzapine particle size. The solubility of olanzapine from the FDT was observed to be nearly four and a half times greater than the pure drug. Results obtained from dissolution studies showed that olanzapine FDT significantly improved the dissolution rate of the drug compared with the physical mixture (PM and the pure drug. More than 90% of olanzapine in FDT dissolved within 5 minutes, compared to only 19.78% of olanzapine pure drug dissolved over the course of 60 minutes. In a stability test, the release profile of the FDT was unchanged, as compared to the freshly prepared FDT after 90 days of storing.O objetivo do presente estudo foi desenvolver comprimidos liofilizados de olanzapina (FDT. A solubilidade e a taxa de dissolução da olanzapina, fracamente solúvel em água, foram melhoradas com a preparação de comprimidos liofilizados de olanzapina usando a técnica de liofilização. O FDT foi preparado por dispersão do fármaco em solução aquosa de materiais altamente solúveis em água, como gelatina

  17. Size and molecular flexibility of sugars determine the storage stability of freeze-dried proteins.

    Science.gov (United States)

    Tonnis, W F; Mensink, M A; de Jager, A; van der Voort Maarschalk, K; Frijlink, H W; Hinrichs, W L J

    2015-03-02

    Protein-based biopharmaceuticals are generally produced as aqueous solutions and stored refrigerated to obtain sufficient shelf life. Alternatively, proteins may be freeze-dried in the presence of sugars to allow storage stability at ambient conditions for prolonged periods. However, to act as a stabilizer, these sugars should remain in the glassy state during storage. This requires a sufficiently high glass transition temperature (Tg). Furthermore, the sugars should be able to replace the hydrogen bonds between the protein and water during drying. Frequently used disaccharides are characterized by a relatively low Tg, rendering them sensitive to plasticizing effects of residual water, which strongly reduces the Tg values of the formulation. Larger sugars generally have higher Tgs, but it is assumed that these sugars are limited in their ability to interact with the protein due to steric hindrance. In this paper, the size and molecular flexibility of sugars was related to their ability to stabilize proteins. Four diverse proteins varying in size from 6 kDa to 540 kDa were freeze-dried in the presence of different sugars varying in size and molecular flexibility. Subsequently, the different samples were subjected to an accelerated stability test. Using protein specific assays and intrinsic fluorescence, stability of the proteins was monitored. It was found that the smallest sugar (disaccharide trehalose) best preserved the proteins, but also that the Tg of the formulations was only just high enough to maintain sufficient vitrification. When trehalose-based formulations are exposed to high relative humidities, water uptake by the product reduces the Tgs too much. In that respect, sugars with higher Tgs are desired. Addition of polysaccharide dextran 70 kDa to trehalose greatly increased the Tg of the formulation. Moreover, this combination also improved the stability of the proteins compared to dextran only formulations. The molecularly flexible oligosaccharide

  18. ALVEOLAR BONE REGENERATION AFTER DEMINERALIZED FREEZE DRIED BONE ALOGRAFT (DFDBA BONE GRAFTING

    Directory of Open Access Journals (Sweden)

    Sri Oktawati

    2006-04-01

    Full Text Available Periodontal treatment by conventional way will result in healing repair, which easily cause recurrence. Modification of treatment should be done to get an effective result, that is the regeneration of alveolar bone and to reduce inflammation. The objective of this study is to determine the alveolar bone regeneration after using DFDBA (Demineralized Freeze Dried Bone Allograft. Quasi experimental designs with pre and post test method was used in this study. From 13 patients, 26 defects got conventional or regenerative treatment. The indicator of alveolar bone regenaration in bone height in radiographic appearance and level of osteocalsin in gingival crevicular fluid (GCF were checked before and after the treatment, then the changes that occurred were analyzed. The result of the research showed that alveolar bone regeneration only occurred to the group of regenerative treatment using DFDBA. The conclusion is the effective periodontal tissue regeneration occurred at regenerative treatment by using DFDBA, and the osteocalsin in GCF can be used as indicator of bone growth.

  19. Dietary feeding of freeze-dried whole cranberry inhibits intestinal tumor development in Apcmin/+ mice

    Science.gov (United States)

    Dong, Wenxiao; Zhang, Yujie; Wang, Sinan; Xie, Runxiang; Wang, Bangmao; Cao, Hailong

    2017-01-01

    It is increasingly perceived that dietary components have been linked with the prevention of intestinal cancer. Cranberry is a rich source of phenolic constituents and non-digestible fermentable dietary fiber, which shows anti-proliferation effect in colorectal cancer cells. Herein, we investigated the efficacy of long-term cranberry diet on intestinal adenoma formation in Apcmin/+ mice. Apcmin/+ mice were fed a basal diet or a diet containing 20% (w/w) freeze-dried whole cranberry powder for 12 weeks, and the number and size of tumors were recorded after sacrifice. Our results showed that cranberry strongly prevented the growth of intestinal tumors by 33.1%. Decreased cell proliferation and increased apoptosis were observed in tumors of cranberry-fed mice. Cranberry diet reduced the expression profile of colonic inflammatory cytokines (IFN-γ, IL-1β and TNF-α) accompanied with increased levels of anti-inflammatory cytokines (IL-4 and IL-10). Moreover, the number of colonic goblet cells and MUC2 production were increased, and the intestinal barrier function was also improved. In addition, cranberry diet increased caecal short chain fatty acids concentrations, and down-regulated epidermal growth factor receptor signaling pathway. These data firstly show the efficacy and associated mechanisms of cranberry diet on intestinal tumor growth in Apcmin/+ mice, suggesting its chemopreventive potential against intestinal cancer. PMID:29228651

  20. Microencapsulation of ethanol extract propolis by maltodextrin and freeze-dried preparation

    Science.gov (United States)

    Mangiring, Getta Austin; Pratami, Diah Kartika; Hermansyah, Heri; Wijanarko, Anondho; Rohmatin, Etin; Sahlan, Muhamad

    2018-02-01

    Propolis has been known to have many benefits for human health, such as anti-cancer, anti-tumor, anti-oxidant, anti-bacterial, and anti-inflammatory. Currently in Indonesia there are quite a lot of propolis-based products, such as soap, toothpaste, skin cream, or health products in liquid form. However, there is still no propolis product in powder form. In this research, microencapsulation of propolis using maltodextrin coating with freeze drying method will be done. Propolis powder has been tested for polyphenols and it was found that crude propolis (175 ml : 75 gr) had the highest polyphenols content in powder form, 434,438 µg /mL. Soft propolis (125 ml : 125 gr) has 4.533% of moisture content, which was the lowest result in these study. And also, the soft propolis (125 ml : 125 gr) has the highest solubility in water with 69% as the result. Propolis powder that has the highest solubility can be seen morphology using Scanning Electron Mocroscope (SEM). The result of the SEM test showed that the propolised powder form did not alter the morphology of maltodextrin. This indicates the success of microencapsulation, because the form of the coating agent maltodextrin was also not uniform.

  1. DEHYDRATION OF CHEESE BY HOT AIR, MICROWAVE AND FREEZE-DRYING

    Directory of Open Access Journals (Sweden)

    ANA RITA C. PINHO

    2017-12-01

    Full Text Available The objective of this work was to study the dehydration of skim cheese through different methods, in particular by hot air, microwave and freeze-drying, in order to assess which of these methods would be more suitable for the development of a new product (cheese snack. For the three processes of dehydration, several temperatures, powers and times were used, respectively. The drying time was optimized to allow the water activity of the final product to be between 0.3 and 0.4. The color and texture of the product obtained by the three processes were evaluated, and the nutritional analysis (protein, lipids, ash of the product dried by hot air at 52 ºC and by microwave at 750 W and 850 W was performed. The sensory analysis of the microwave dehydrated products was also carried out. The results obtained revealed that the temperature played a relevant role in the drying time and the hardness of the product. In the dehydration by microwave, the power of 850 W resulted in a lower drying time and a better color preservation, but in a high hardness of the samples. Among the three processes studied, the microwave drying was the fastest for the water removal from the cheese.

  2. Use of soft sensors to monitor a pharmaceuticals freeze-drying process in vials.

    Science.gov (United States)

    Bosca, Serena; Barresi, Antonello A; Fissore, Davide

    2014-03-01

    This paper presents a soft sensor that can be effectively used for in-line monitoring of the primary drying step of a pharmaceuticals freeze-drying process in vials. Process modeling and product temperature measurements are used to estimate the residual amount of ice in the vial and the heat transfer coefficient from the shelf to the product in the vial. The resistance of the dried cake to vapor flow is determined through the heat balance equation at the interface of sublimation. Mathematical simulation and experimental tests have been carried out to validate the estimations provided by the soft sensor. Accurate estimations of the dynamics of the product until the end of primary drying are obtained, as well as of the heat and mass transfer coefficients, even in the case of a highly non-uniform batch. The reduction in the number of variables directly estimated by the soft sensor allows increasing the robustness of the tool with respect to other sensors presented in the literature. The proposed soft sensor is thus effective for process monitoring and it allows using model-based tools for cycle development in lab-scale units, where thermocouples are usually available, and for process monitoring in industrial-scale freeze-dryers, in case wireless sensors are used.

  3. Preparation and characterization of freeze-dried 2-methoxyestradiol nanoparticle powders.

    Science.gov (United States)

    Du, Bin; Li, Xiao-Tian; Zhao, Ya; A, You-Mei; Zhang, Zhen-Zhong

    2010-07-01

    Poorly water-soluble compounds are difficult to develop as drug products using conventional formulation techniques and are frequently abandoned early in discovery. In the present study, a nanoprecipitation-high-frequency ultrasonication technique was adapted to produce drug nanosuspensions. The formulation of 2-methoxyestradiol (2-ME) as nanosuspension, either in the form of lyophilized powder or granules, was very successful in enhancing dissolution rate, more 45 times than bulk 2-ME being dissolved in the first 10 min. The increase in vitro dissolution rate may favourably affect bioavailability. The nanosuspension produced was then characterized using particle size determination, zeta potential measurement, scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and X-ray analysis. Results showed that freeze-dried nanosuspension composed of amorphous particles with a mean particle size of 244 +/- 10.6 nm (polydispersity index of 0.21 +/- 0.02) was obtained. Physical stability studies showed that 2-ME nanosuspension remained homogeneous with slight increase in mean particle size and polydispersity index over a 3-month period.

  4. Stability of freeze-dried vaginal Lactobacillus strains in the presence of different lyoprotectors.

    Science.gov (United States)

    Juárez Tomás, María Silvina; Bru, Elena; Martos, Gladys; Nader-Macías, María Elena

    2009-05-01

    The industrial use of lactic acid bacteria as probiotic cultures depends on the preservation techniques employed, which are required to guarantee stable cultures in terms of viability and functional activity. The aim of this study was to evaluate the effects of 12% lactose and 12% sucrose suspended in water or reconstituted skim milk on the survival and expression of beneficial characteristics during freeze-drying and subsequent storage of 6 vaginal lactobacilli strains. A cubic polynomial model was also used for the first time to evaluate the effects of different protectors on survival behavior during storage. Different survival patterns were observed among the strains considered. The presence of both lactose and sucrose in water or in 6% skim milk as the suspension medium proved to be effective in maintaining a high degree of survival and expression of potentially probiotic characteristics (production of antimicrobial substances or auto-aggregation capabilities) of most strains after lyophilization and long-term storage. This study constitutes a valuable step to obtain concentrated cultures with the highest stability of microorganisms for pharmaceutical purposes.

  5. Clinical uses of radiosterilized freeze-dried human bone: its application in buccomaxillary surgery

    International Nuclear Information System (INIS)

    Wolfsohn, B.; Taramasso, F.; Godoy, J.; Wodowoz, O.; Saldias, M.; Silva, W.; Machin, D.; Sanchez, G.; Alvarez, I.

    2008-01-01

    Full text: The objective of this paper is to evaluate the uses of different human bone tissue allografts in bucomaxillary surgery between 2005 and 2007. Presentation of our experience using single freeze dried bone allografts and associated to bovine collagen membranes (commercial registered). Twenty patients were treated with cortical struts, cancellous chips, morsellized and morsellized demineralized bone. All the grafts were processed at the INDT multi tissue bank from cardiac arrest and brain death cadaveric donors. All the tissues were radiosterilized by Gamma radiation. Bone allografts were used: 1) to optimize bone support increasing maxillar or mandible bone before implant surgery. 2) in dehiscences and fissures during the implant surgery. 3) to stimulate bone regeneration in alveolar cavity, post-apicectomies, and cystectomies as well as for bone defects. The patients were periodically evaluated using standardized protocols. All the cases were successful showing clinic and radiologically osseointegration after 6 and 12 months. Results were evaluated considering surgical technique and patients bucomaxillary rehabilitation. Clinical uses of bone allografts confirm in our experience, as scientific literature outcomes shows, are useful in patients that refuses autografts ablation. (Author)

  6. Solidification drug nanosuspensions into nanocrystals by freeze-drying: a case study with ursodeoxycholic acid.

    Science.gov (United States)

    Ma, Yue-Qin; Zhang, Zeng-Zhu; Li, Gang; Zhang, Jing; Xiao, Han-Yang; Li, Xian-Fei

    2016-03-01

    To elucidate the effect of solidification processes on the redispersibility of drug nanocrystals (NC) during freeze-drying, ursodeoxycholic acid (UDCA) nanosuspensions were transformed into UDCA-NC via different solidification process included freezing and lyophilization. The effect of different concentrations of stabilizers and cryoprotectants on redispersibility of UDCA-NC was investigated, respectively. The results showed that the redispersibility of UDCA-NC was RDI-20 °C lyophilization. The hydroxypropylmethylcellulose and PVPK30 were effective to protect UDCA-NC from damage during lyophilization, which could homogeneously adsorb into the surface of NC to prevent from agglomerates. The sucrose and glucose achieved excellent performance that protected UDCA-NC from crystal growth during lyophilization, respectively. It was concluded that UDCA-NC was subjected to agglomeration during solidification transformation, and the degree of agglomeration suffered varied with the type and the amounts of stabilizers used, as well as different solidification conditions. The PVPK30-sucrose system was more effective to protect UDCA-NC from the damage during solidification process.

  7. Multi-scale mechanical response of freeze-dried collagen scaffolds for tissue engineering applications.

    Science.gov (United States)

    Offeddu, Giovanni S; Ashworth, Jennifer C; Cameron, Ruth E; Oyen, Michelle L

    2015-02-01

    Tissue engineering has grown in the past two decades as a promising solution to unresolved clinical problems such as osteoarthritis. The mechanical response of tissue engineering scaffolds is one of the factors determining their use in applications such as cartilage and bone repair. The relationship between the structural and intrinsic mechanical properties of the scaffolds was the object of this study, with the ultimate aim of understanding the stiffness of the substrate that adhered cells experience, and its link to the bulk mechanical properties. Freeze-dried type I collagen porous scaffolds made with varying slurry concentrations and pore sizes were tested in a viscoelastic framework by macroindentation. Membranes made up of stacks of pore walls were indented using colloidal probe atomic force microscopy. It was found that the bulk scaffold mechanical response varied with collagen concentration in the slurry consistent with previous studies on these materials. Hydration of the scaffolds resulted in a more compliant response, yet lesser viscoelastic relaxation. Indentation of the membranes suggested that the material making up the pore walls remains unchanged between conditions, so that the stiffness of the scaffolds at the scale of seeded cells is unchanged; rather, it is suggested that thicker pore walls or more of these result in the increased moduli for the greater slurry concentration conditions. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Sample preservation for determination of organic compounds: microwave versus freeze-drying

    International Nuclear Information System (INIS)

    Popp, M.; Lied, W.; Meyer, A.J.; Richter, A.; Schiller, P.; Schwitte, H.

    1996-01-01

    In search of a reliable drying method, which might be used even under field conditions, microwave drying was compared to freeze-drying of plant material. Leaves of Ananas comosus and Avicennia germinans as well as buds and phloem of Acer pseudoplatanus were used and checked for one or more of the following substances: sugars, sugar alcohols, organic and amino acids, total nitrogen, and glycinebetaine. With most samples good agreement was achieved between the two drying methods. Only in the case of the Ananas comosus leaves, which exhibited low pH and high water content, did appreciable differences occur in organic and amino acids. Besides that, sucrose was the compound most susceptible to alterations, which was especially evident when leaves of Sambucus nigra were dried in the two different compartments (condenser compartment, drying bell jar) of the freeze-dryer in use. For Ananas comosus leaf samples it was shown that microwaving can also be used prior to extraction of tissue sap. (author)

  9. Measurement of final container residual moisture in freeze-dried biological products.

    Science.gov (United States)

    May, J C; Wheeler, R M; Etz, N; Del Grosso, A

    1992-01-01

    The Center for Biologics Evaluation and Research has changed its regulations pertaining to residual moisture in freeze-dried biological products as published in Title 21 of the Code of Federal Regulations for Food and Drugs. The new regulation requires that each lot of dried product be tested for residual moisture and meet and not exceed established limits as specified by an approved method on file in the product license application. The gravimetric or loss-on-drying method is no longer listed as the required method; the 1.0% moisture limit is no longer specifically stated in the regulation. These revisions were made to bring the regulation into line with changes in residual moisture testing methods and the results obtained when new testing methods were applied to the determination of residual moisture. This is illustrated with data for Measles Virus Vaccine Live and Haemophilus b Polysaccharide Vaccine using final container residual moisture test results obtained by the gravimetric, coulometric Karl Fischer, thermogravimetric and thermogravimetric/mass spectrometric methods. Guidelines for the determination of residual moisture in dried biological products have been issued to describe residual moisture test methods and procedures used to set product residual moisture limits. For most products levels of residual moisture should be low, usually from less than 1.0% to 3.0%, so that the viability, immunologic potency and therefore the stability of the product is not compromised over time.

  10. Freeze dried chitosan/ poly-(glutamic acid) microparticles for intestinal delivery of lansoprazole.

    Science.gov (United States)

    Singh, Mangla Nand; Yadav, Hemant K S; Ram, Munshi; Shivakumar, H G

    2012-01-01

    Lansoprazole sodium is a proton pump inhibitor used in treating gastroesophageal reflux disease (GERD). It is highly acid-labile and presents many formulation challenges. Therefore, this drug needs to be protected from the harsh environment in the stomach. In order to achieve this, a pH-sensitive microparticle system composed of chitosan and γ- poly-(glutamic acid) was prepared and loaded with Lansoprazole. The prepared microparticles were not stable in gastric pH. To overcome this problem microparticles were freez-dried and filled in an enteric-coated capsule. Upon oral administration, the enteric-coated capsule remained intact in the acidic environment of the stomach, but dissolved rapidly in the distal segment of the GIT. Consequently, all the microparticles loaded in the capsule were brought into the intestine, thus enhancing the intestinal absorption of drug. Drug encapsulation efficiency of formulation F3 was found to be 82.82 % and in vitro release of prepared formulation F3 was found to be 94% after 8 h of dissolution in 7.4 pH phosphate buffer. FTIR and DSC studies showed no interaction between the drug and polymer. The formulation showed good swelling property. SEM photographs showed that microparticles are spherical and lies in size range of 300-400 μm. From the above, it can be concluded that the prepared chitosan/ γ-poly-(glutamic acid) microparticles can be used as carriers for the intestinal delivery of acid liable drugs such as lansoprazole.

  11. Spray Freeze-drying - The Process of Choice for Low Water Soluble Drugs?

    International Nuclear Information System (INIS)

    Leuenberger, H.

    2002-01-01

    Most of the novel highly potent drugs, developed on the basis of modern molecular medicine, taking into account cell surface recognition techniques, show poor water solubility. A chemical modification of the drug substance enhancing the solubility often decreases the pharmacological activity. Thus, as an alternative an increase of the solubility can be obtained by the reduction of the size of the drug particles. Unfortunately, it is often difficult to obtain micro or nanosized drug particles by classical or more advanced crystallization using supercritical gases or by milling techniques. In addition, nanosized particles are often not physically stable and need to be stabilized in an appropriate matrix. Thus, it may be of interest to manufacture directly nanosized drug particles stabilized in an inert hydrophilic matrix, i.e. nanostructured and nanocomposite systems. Solid solutions and solid dispersions represent nanostructured and nanocomposite systems. In this context, the use of the vacuum-fluidized-bed technique for the spray-drying of a low water soluble drug cosolubilized with a hydrophilic excipient in a polar organic solvent is discussed. In order to avoid the use of organic solvents, a special spray-freeze-drying technique working at atmospheric pressure is presented. This process is very suitable for temperature and otherwise sensitive drugs such as pharmaproteins

  12. Acetabular reconstruction with human and bovine freeze-dried bone grafts and a reinforcement device

    Directory of Open Access Journals (Sweden)

    Ricardo Rosito

    2008-01-01

    Full Text Available BACKGROUND: This is a cohort trial (1997-2005 of 49 patients submitted to an acetabular component revision of a total hip arthroplasty, using impacted human and bovine freeze-dried cancellous bone grafts (H&FDBG and a reinforcement device. OBJECTIVE: To compare clinical/radiographic graft incorporation capability between cancellous bone grafts. PATIENTS/METHODS: There were two groups: I (n=26 receiving human grafts and II (n=25 receiving bovine grafts. The average follow-up times were 55 and 49 months, respectively. Clinical analysis was based on the Merle d'Aubigné and Postel score, and the radiographic analysis involved an established score based on Conn's et al. criteria for radiographic bone incorporation. RESULTS: No clinical/radiographic differences were found between the groups and both showed an overall rate of 88.5% and 76% of graft incorporation (p=0.424. CONCLUSION: The results presented here are comparable to those in the literature with the use of deep-FG. Therefore, cancellous bone grafts can be safely and adequately used in acetabular component revision in total hip arthroplasty.

  13. On the Design of a Fuzzy Logic-Based Control System for Freeze-Drying Processes.

    Science.gov (United States)

    Fissore, Davide

    2016-12-01

    This article is focused on the design of a fuzzy logic-based control system to optimize a drug freeze-drying process. The goal of the system is to keep product temperature as close as possible to the threshold value of the formulation being processed, without trespassing it, in such a way that product quality is not jeopardized and the sublimation flux is maximized. The method involves the measurement of product temperature and a set of rules that have been obtained through process simulation with the goal to obtain a unique set of rules for products with very different characteristics. Input variables are the difference between the temperature of the product and the threshold value, the difference between the temperature of the heating fluid and that of the product, and the rate of change of product temperature. The output variables are the variation of the temperature of the heating fluid and the pressure in the drying chamber. The effect of the starting value of the input variables and of the control interval has been investigated, thus resulting in the optimal configuration of the control system. Experimental investigation carried out in a pilot-scale freeze-dryer has been carried out to validate the proposed system. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  14. Comparative proteomic analysis of the sun- and freeze-dried earthworm Eisenia fetida with differentially thrombolytic activities.

    Science.gov (United States)

    Fu, Zhirong; Zhang, Lin; Liu, Xiaobao; Zhang, Yanzhen; Zhang, Qianlan; Li, Ximin; Zheng, Wen; Sun, Lianli; Tian, Jingkui

    2013-05-27

    The dried earthworm is a traditional thrombolytic medicine in East Asia. Its thrombolytic mechanism has been extensively studied. However, the effects of drying process on thrombolysis were rarely investigated. Herein, we compared the thrombolytic activity of earthworm Eisenia fetida processed by sun-drying to that by freeze-drying. Fibrin plate and blood clot lysis assays showed that freeze-dried earthworms gave dramatically higher fibrinolytic and thrombolytic activities than the sun-dried earthworms. To address the thrombolytic difference, comparative proteomic analysis was carried out using fibrin zymography and two-dimensional gel electrophoresis (2-DE). The freeze- and sun-dried earthworms generated remarkably different 2-DE protein spot patterns. A total of 126 differential protein spots were detected, 83 of them were identified by matrix-assisted laser desorption/ionization-tandem time-of-flight mass spectrometry and database searching with 13 quantitative changes and 70 qualitative changes. Five of these differential proteins were identified as fibrinolytic proteases (lumbrokinases), responsible for dissolving fibrin, the main protein component of thrombus. The total abundance of these fibrinolytic proteases in the freeze-dried earthworms was significantly higher, consistent with the results of fibrin zymography. Therefore, the higher concentration of fibrinolytic enzymes along with their broad substrate specificity explained the stronger fibrinolytic and thrombolytic activities of the freeze-dried earthworms. This study suggests that freeze-drying represents an improved processing method for earthworm as the thrombolytic therapy in the future. Thrombosis has become one of the biggest concerns all over the world. The dried earthworms have been intensively used as thrombolytic agents. Its thrombotic mechanism has been studied by the modern pharmacological researches. However, the drying procedure of the earthworm and its effects on the thrombolysis were

  15. Freeze-Drying of L-Arginine/Sucrose-Based Protein Formulations, Part 2: Optimization of Formulation Design and Freeze-Drying Process Conditions for an L-Arginine Chloride-Based Protein Formulation System.

    Science.gov (United States)

    Stärtzel, Peter; Gieseler, Henning; Gieseler, Margit; Abdul-Fattah, Ahmad M; Adler, Michael; Mahler, Hanns-Christian; Goldbach, Pierre

    2015-12-01

    We recently reported that the presence of chloride counter ions in freeze-dried l-arginine/sucrose formulations provided the greatest protein stability, but led to low collapse temperatures and glass transition temperatures of the freeze concentrates. The objectives of this study were to identify l-arginine chloride-based formulations and optimize freeze-drying process conditions to deliver a freeze-dried product with good physical quality attributes (including cake appearance, residual moisture, and reconstitution time). Additional properties were tested such as thermal properties, cake microstructure, and protein physical stability. Excipient concentrations were varied with and without a model protein (bovine serum albumin, BSA). Formulations were frozen with and without annealing or with and without controlled nucleation. Primary drying was conducted at high and low shelf temperature. Cakes with least defects and optimum physical attributes were achieved when protein to excipient ratios were high. Controlled nucleation led to elegant cakes for most systems at a low shelf temperature. Replacing BSA by a monoclonal antibody showed that protein (physical) stability was slightly improved under stress storage temperature (i.e., 40°C) in the presence of a low concentration of l-arginine in a sucrose-based formulation. At higher l-arginine concentrations, cake defects increased. Using optimized formulation design, addition of l-arginine chloride to a sucrose-based formulation provided elegant cakes and benefits for protein stability. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  16. Effect of freeze-drying on viability and in vitro probiotic properties of a mixture of lactic acid bacteria and yeasts isolated from kefir.

    Science.gov (United States)

    Bolla, Patricia A; Serradell, María de los Angeles; de Urraza, Patricio J; De Antoni, Graciela L

    2011-02-01

    The effect of freeze-drying on viability and probiotic properties of a microbial mixture containing selected bacterial and yeast strains isolated from kefir grains (Lactobacillus kefir, Lactobacillus plantarum, Lactococcus lactis, Saccharomyces cerevisiae and Kluyveromyces marxianus) was studied. The microorganisms were selected according to their potentially probiotic properties in vitro already reported. Two types of formulations were performed, a microbial mixture (MM) suspended in milk and a milk product fermented with MM (FMM). To test the effect of storage on viability of microorganisms, MM and FMM were freeze-dried and maintained at 4°C for six months. After 180 days of storage at 4°C, freeze-dried MM showed better survival rates for each strain than freeze-dried FMM. The addition of sugars (trehalose or sucrose) did not improve the survival rates of any of the microorganisms after freeze-drying. Freeze-drying did not affect the capacity of MM to inhibit growth of Shigella sonnei in vitro, since the co-incubation of this pathogen with freeze-dried MM produced a decrease of 2 log in Shigella viability. The safety of freeze-dried MM was tested in mice and non-translocation of microorganisms to liver or spleen was observed in BALB/c mice feed ad libitum during 7 or 20 days. To our knowledge, this is the first report about the effect of freeze-drying on viability, in vitro probiotic properties and microbial translocation of a mixture containing different strains of both bacteria and yeasts isolated from kefir.

  17. Effect of ultrasound and blanching pretreatments on polyacetylene and carotenoid content of hot air and freeze dried carrot discs.

    Science.gov (United States)

    Rawson, A; Tiwari, B K; Tuohy, M G; O'Donnell, C P; Brunton, N

    2011-09-01

    The effect of ultrasound and blanching pretreatments on polyacetylene (falcarinol, falcarindiol and falcarindiol-3-acetate) and carotenoid compounds of hot air and freeze dried carrot discs was investigated. Ultrasound pretreatment followed by hot air drying (UPHD) at the highest amplitude and treatment time investigated resulted in higher retention of polyacetylenes and carotenoids in dried carrot discs than blanching followed by hot air drying. Freeze dried samples had a higher retention of polyacetylene and carotenoid compounds compared to hot air dried samples. Color parameters were strongly correlated with carotenoids (p<0.05). This study shows that ultrasound pretreatment is a potential alternative to conventional blanching treatment in the drying of carrots. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Freeze-Drying Above the Glass Transition Temperature in Amorphous Protein Formulations While Maintaining Product Quality and Improving Process Efficiency.

    Science.gov (United States)

    Depaz, Roberto A; Pansare, Swapnil; Patel, Sajal Manubhai

    2016-01-01

    This study explored the ability to conduct primary drying during lyophilization at product temperatures above the glass transition temperature of the maximally freeze-concentrated solution (Tg′) in amorphous formulations for four proteins from three different classes. Drying above Tg′ resulted in significant reductions in lyophilization cycle time. At higher protein concentrations, formulations freeze dried above Tg′ but below the collapse temperature yielded pharmaceutically acceptable cakes. However, using an immunoglobulin G type 4 monoclonal antibody as an example, we found that as protein concentration decreased, minor extents of collapse were observed in formulations dried at higher temperatures. No other impacts to product quality, physical stability, or chemical stability were observed in this study among the different drying conditions for the different proteins. Drying amorphous formulations above Tg′, particularly high protein concentration formulations, is a viable means to achieve significant time and cost savings in freeze-drying processes.

  19. Safety assessment of freeze-dried powdered Cassiae Semen: evaluation of chronic toxicity (26-week in Sprague-Dawley rats

    Directory of Open Access Journals (Sweden)

    Yanyu Pei

    Full Text Available There is a lack of safety assessment data regarding the long-term consumption of Cassiae Semen (Leguminosae, the seeds of Cassia obtusifolia L. and Cassia tora L.. Thus, we evaluated the toxicity of freeze-dried powdered Cassiae Semen in male and female Sprague-Dawley rats. Rats were intragastrically administered freeze-dried powdered Cassiae Semen at a dose of 0.5, 2.2, or 10.0 g/kg body weight/day for 26 weeks; several variables were assessed after 13 and 26 weeks as well as after a 4-week recovery period. No mortality was observed in the treated animals, and body weight increased in a dose-dependent manner. The total bilirubin (TBIL levels also displayed a dose-dependent relationship. In males, at 26 weeks, there were significant increases in relative kidney weights in the 2.2 and 10.0 g/kg groups compared with that in the negative control group (p < 0.05 or p < 0.01. Pigment deposition in the epithelial cells of the renal proximal convoluted tubules and atrophy or regeneration of renal tubules were observed in the 10.0 g/kg group after 26 weeks, and these changes were not fully reversed after the 4-week recovery period. Under the studied conditions, the primary toxicity organs for freeze-dried powdered Cassiae Semen in the 10.0 g/kg group were the kidneys. Keywords: Cassiae Semen, Freeze-dried powder, Chronic toxicity, Toxicity organs

  20. Biophysical evaluation of aminoclay as an effective protectant for protein stabilization during freeze-drying and storage

    Directory of Open Access Journals (Sweden)

    Song JG

    2016-12-01

    Full Text Available Jae Geun Song, Sang Hoon Lee, Hyo-Kyung Han College of Pharmacy, Dongguk University, Goyang, South Korea Abstract: This study aimed to evaluate aminoclay (3-aminopropyl-functionalized magnesium phyllosilicate as an effective protectant for the stabilization of protein formulation in freeze-drying. Bovine serum albumin (BSA, as a model protein, was freeze-dried with aminoclay at various concentrations, and the effects of aminoclay on the structural stability of proteins were compared with those of the conventional stabilizers. The structural characteristics of the protein were determined by size exclusion chromatography (SEC, circular dichroism (CD, and Fourier transform infrared (FTIR spectroscopy. Furthermore, physicochemical and morphological characteristics were examined by X-ray powder diffraction (XRPD, differential scanning calorimetry (DSC, and scanning electron microscopy (SEM. XRPD and DSC patterns indicated that the glass transition temperature (Tg of the amorphous formulation of aminoclay mixed with proteins was gradually elevated as the concentration of aminoclay increased. FTIR and CD spectral analysis suggested that the protein structure was well maintained with aminoclay during the freeze-drying process and 3 months of storage at 4°C and 40°C. Furthermore, aminoclay conferred the greatest protection against aggregation and retained the monomer content of BSA even at a high temperature. The morphological characteristics of lyophilized proteins were also well conserved during the storage with aminoclay. These results suggested that aminoclay may be useful as an alternative stabilizer for maintaining the structural stability of protein formulations. Keywords: aminoclay, cryoprotectant, lyoprotectant, freeze-drying, protein, stability

  1. Evaluation of 3D-Printed Polycaprolactone Scaffolds Coated with Freeze-Dried Platelet-Rich Plasma for Bone Regeneration

    OpenAIRE

    Li, Junda; Chen, Meilin; Wei, Xiaoying; Hao, Yishan; Wang, Jinming

    2017-01-01

    Three-dimensional printing is one of the most promising techniques for the manufacturing of scaffolds for bone tissue engineering. However, a pure scaffold is limited by its biological properties. Platelet-rich plasma (PRP) has been shown to have the potential to improve the osteogenic effect. In this study, we improved the biological properties of scaffolds by coating 3D-printed polycaprolactone (PCL) scaffolds with freeze-dried and traditionally prepared PRP, and we evaluated these scaffold...

  2. Stabilization of protein by freeze-drying in the presence of trehalose: a case study of tubulin

    Czech Academy of Sciences Publication Activity Database

    Dráber, Pavel; Sulimenko, Vadym; Sulimenko, Tetyana; Dráberová, Eduarda

    2014-01-01

    Roč. 1129, February (2014), s. 443-458 ISSN 1064-3745 R&D Projects: GA MŠk LH12050; GA AV ČR M200521203; GA ČR GAP302/10/1701; GA ČR GPP302/11/P709 Institutional support: RVO:68378050 Keywords : Freeze-drying * Microtubules * Stability * Trehalose * Tubulin Subject RIV: EB - Genetics ; Molecular Biology

  3. Encapsulation and subsequent freeze-drying of Lactobacillus reuteri CRL 1324 for its potential inclusion in vaginal probiotic formulations.

    Science.gov (United States)

    Juárez Tomás, María Silvina; De Gregorio, Priscilla Romina; Leccese Terraf, María Cecilia; Nader-Macías, María Elena Fátima

    2015-11-15

    Probiotic formulations must include a high number of viable and active microorganisms. In this work, the survival of human vaginal Lactobacillus reuteri CRL 1324 during encapsulation, lyophilization and storage, and the activity of encapsulated and/or freeze-dried bacterial cells were evaluated. Extrusion-ionic gelation technique was applied to encapsulate L. reuteri CRL 1324, using xanthan and gellan. Encapsulated and free bacterial cells were freeze-dried with or without lactose and skim milk as lyoprotectors. The different systems obtained were stored at room temperature and at 4°C for 150days. The following determinations were performed: L. reuteri CRL 1324 viability, microorganism released from capsules, survival in a medium simulating the vaginal fluid and maintenance of beneficial properties (growth inhibition of opportunistic pathogenic Streptococcus agalactiae NH 17 and biofilm formation). L. reuteri CRL 1324 encapsulation was efficient, allowing the recovery of a high number of entrapped lactobacilli. The survival of encapsulated L. reuteri during lyophilization and storage was significantly higher in the presence of lyoprotectors. At the end of storage, the highest numbers of viable cells were obtained in free or encapsulated cells freeze-dried with lyoprotectors, stored at 4°C. Encapsulated and/or lyophilized L. reuteri cells maintained their viability in simulated vaginal fluid as well as the ability to inhibit S. agalactiae NH 17 growth and to form biofilm. Encapsulated and freeze-dried L. reuteri CRL 1324 can be included in a suitable pharmaceutical form for vaginal application to prevent or treat urogenital infections in women. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Validation of a multipoint near-infrared spectroscopy method for in-line moisture content analysis during freeze-drying.

    Science.gov (United States)

    Kauppinen, Ari; Toiviainen, Maunu; Lehtonen, Marko; Järvinen, Kristiina; Paaso, Janne; Juuti, Mikko; Ketolainen, Jarkko

    2014-07-01

    This study assessed the validity of a multipoint near-infrared (NIR) spectroscopy method for in-line moisture content analysis during a freeze-drying process. It is known that the moisture content affects the stability of a freeze-dried product and hence it is a major critical quality attribute. Therefore assessment of the validity of an analytical method for moisture content determination is vital to ensure the quality of the final product. An aqueous sucrose solution was used as the model formulation of the study. The NIR spectra were calibrated to the moisture content using partial least squares (PLS) regression with coulometric Karl Fischer (KF) titration as the reference method. Different spectral preprocessing methods were compared for the PLS models. A calibration model transfer protocol was established to enable the use of the method in the multipoint mode. The accuracy profile was used as a decision tool to determine the validity of the method. The final PLS model, in which NIR spectra were preprocessed with standard normal variate transformation (SNV), resulted in low root mean square error of prediction value of 0.04%-m/v, i.e. evidence of sufficient overall accuracy of the model. The validation results revealed that the accuracy of the model was acceptable within the moisture content range 0.16-0.70%-m/v that is specific for the latter stages of the freeze-drying process. In addition, the results demonstrated the method's reliable in-process performance and robustness. Thus, the multipoint NIR spectroscopy method was proved capable of providing in-line evaluation of moisture content and it is readily available for use in laboratory scale freeze-drying research and development. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Preparation of a ceramic superconductor from ultrafine particles by freeze-dry process in Ba-Y-Cu-O system

    International Nuclear Information System (INIS)

    Chen Zuyao; Qian Yitai; Wan Yanjian; Rong Jingfang; Zhang Han; Pan Guoqiang; Zhao Yong; Zhang Qirui

    1989-01-01

    Freeze-dry technique is first reported for preparing ceramic ultrafines. The single-phase complex oxide Ba 2 YCu 3 O/sub 9-δ/, a poly-crystallized compound, and ceramic superconductor have been synthesized successfully. The experimental results show that not only is the ceramic superconductor obtained uniform with fine particles and excellent superconductivity, but the conditions for solid reactions are relatively limited

  6. Quantitative risk assessment via uncertainty analysis in combination with error propagation for the determination of the dynamic Design Space of the primary drying step during freeze-drying

    DEFF Research Database (Denmark)

    Van Bockstal, Pieter Jan; Mortier, Séverine Thérèse F.C.; Corver, Jos

    2017-01-01

    Traditional pharmaceutical freeze-drying is an inefficient batch process often applied to improve the stability of biopharmaceutical drug products. The freeze-drying process is regulated by the (dynamic) settings of the adaptable process parameters shelf temperature Ts and chamber pressure Pc...... of a freeze-drying process, allowing to quantitatively estimate and control the risk of cake collapse (i.e., the Risk of Failure (RoF)). The propagation of the error on the estimation of the thickness of the dried layer Ldried as function of primary drying time was included in the uncertainty analysis...

  7. Effects of sugar alcohol and proteins on the survival of Lactobacillus bulgaricus LB6 during freeze drying.

    Science.gov (United States)

    Chen, He; Chen, Shiwei; Chen, Hongli; Wu, Yanyan; Shu, Guowei

    2015-01-01

    Lactobacillus bulgaricus LB6 is a bacterium which was selected in the commercial yoghurt with high angiotensin converting enzyme (ACE) inhibitory activity. Preparation of concentrated starter cultures via freeze drying is of practical importance to dairy and food industries. We optimized the optimal sugar alcohol and proteins for Lactobacillus bulgaricus LB6 during the process of freeze drying using a Plackett-Burman design. In our initial tests survival rate and the number of viable cells were associated with the type of lyoprotectant used and so our optimization protocol focused on increasing survival rate. Substances that had previously had a protective effect during freeze drying were investigated, for example: mannitol, sorbitol, xylitol, meso-erythritol, lactitol, whey protein isolate 90, bovine serum albumin, and whey protein concentrate 80 and soy protein isolate 70. We found that the optimum sugar alcohol and proteins for survival of Lactobacillus bulgaricus LB6 were whey protein concentrate (p = 0.0040 for survival rate), xylitol (p = 0.0067 for survival rate) and sorbitol (p = 0.0073 for survival rate), they showed positive effect (whey protein concentrate and sorbitol) or negative effect (xylitol). The effectiveness of three chosen sugar alcohols and protein implied that they could be used as lyoprotectant for Lactobacillus bulgaricus LB6 in the further research, the optimal composition of sugar alcohol and protein for the lyoprotectant use must be established.

  8. Coupled fluid-thermal analysis of low-pressure sublimation and condensation with application to freeze-drying

    Science.gov (United States)

    Ganguly, Arnab

    Freeze-drying is a low-pressure, low-temperature condensation pumping process widely used in the manufacture of bio-pharmaceuticals for removal of solvents by sublimation. The goal of the process is to provide a stable dosage form by removing the solvent in such a way that the sensitive molecular structure of the active substance is least disturbed. The vacuum environment presents unique challenges for understanding and controlling heat and mass transfer in the process. As a result, the design of equipment and associated processes has been largely empirical, slow and inefficient. A comprehensive simulation framework to predict both, process and equipment performance is critical to improve current practice. A part of the dissertation is aimed at performing coupled fluid-thermal analysis of low-pressure sublimation-condensation processes typical of freeze-drying technologies. Both, experimental and computational models are used to first understand the key heat transfer modes during the process. A modeling and computational framework, validated with experiments for analysis of sublimation, water-vapor flow and condensation in application to pharmaceutical freeze-drying is developed. Augmented with computational fluid dynamics modeling, the simulation framework presented here allows to predict for the first time, dynamic product/process conditions taking into consideration specifics of equipment design. Moreover, by applying the modeling framework to process design based on a design-space approach, it has demonstrated that there is a viable alternative to empiricism.

  9. Microencapsulation of purified amylase enzyme from pitaya (Hylocereus polyrhizus) peel in Arabic gum-chitosan using freeze drying.

    Science.gov (United States)

    Amid, Mehrnoush; Manap, Yazid; Zohdi, Nor Khanani

    2014-03-24

    Amylase is one of the most important enzymes in the world due to its wide application in various industries and biotechnological processes. In this study, amylase enzyme from Hylocereus polyrhizus was encapsulated for the first time in an Arabic gum-chitosan matrix using freeze drying. The encapsulated amylase retained complete biocatalytic activity and exhibited a shift in the optimum temperature and considerable increase in the pH and temperature stabilities compared to the free enzyme. Encapsulation of the enzyme protected the activity in the presence of ionic and non-ionic surfactants and oxidizing agents (H₂O₂) and enhanced the shelf life. The storage stability of amylase is found to markedly increase after immobilization and the freeze dried amylase exhibited maximum encapsulation efficiency value (96.2%) after the encapsulation process. Therefore, the present study demonstrated that the encapsulation of the enzyme in a coating agent using freeze drying is an efficient method to keep the enzyme active and stable until required in industry.

  10. Solidification of liposomes by freeze-drying: the importance of incorporating gelatin as interior support on enhanced physical stability.

    Science.gov (United States)

    Guan, Peipei; Lu, Yi; Qi, Jianping; Niu, Mengmeng; Lian, Ruyue; Wu, Wei

    2015-01-30

    The main purpose of this study was to investigate the effect of gelatin as interior support on the physical stability of freeze-dried liposomes. Anticancer agent paclitaxel (PTX) was selected as a model drug. Freeze-dried liposomes containing interior gelatin support (GLs) were prepared by thin-film dispersion/freeze-drying method. Several properties of the GLs, including entrapment efficiency, particle size and gelation temperature, were extensively characterized. Encapsulation efficiency of conventional liposomes (CLs) and liposomes containing lyoprotectants as interior support dropped to lower than 20% after reconstitution, while GLs still maintained an entrapment efficiency of over 84%. Scanning electron microscopy revealed well preserved liposomal structure of GLs after reconstitution. Meanwhile, the particle size and entrapment efficiency of GLs were also well preserved after reconstitution. In contrary, deformation of CLs and recrystallization of PTX were observed, as well as significant changes in particle size and entrapment efficiency. Taken together, interior gelatin support obviously enhanced the physical stability of liposomes against the lyophilization stress. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Effect of Chemical Stabilizers on the Thermostability and Infectivity of a Representative Panel of Freeze Dried Viruses

    Science.gov (United States)

    Gould, Ernest A.; Charrel, Remi N.; de Lamballerie, Xavier

    2015-01-01

    As a partner of the European Virus Archive (EVA) FP7 project, our laboratory maintains a large collection of freeze-dried viruses. The distribution of these viruses to academic researchers, public health organizations and industry is one major aim of the EVA consortium. It is known that lyophilization requires appropriate stabilizers to prevent inactivation of the virus. However, few studies have investigated the influence of different stabilizers and lyophilization protocols on the thermostability of different viruses. In order to identify optimal lyophilization conditions that will deliver maximum retention of viral infectivity titre, different stabilizer formulations containing trehalose, sorbitol, sucrose or foetal bovine serum were evaluated for their efficacy in stabilizing a representative panel of freeze dried viruses at different storage temperatures (-20°C, +4°C and +20°C) for one week, the two latter mimicking suboptimal shipping conditions. The Tissue Culture Infectious Dose 50% (TCID50) assay was used to compare the titres of infectious virus. The results obtained using four relevant and model viruses (enveloped/non enveloped RNA/DNA viruses) still serve to improve the freeze drying conditions needed for the development and the distribution of a large virus collection. PMID:25923434

  12. Comparative Evaluation of Commercially Available Freeze Dried Powdered Probiotics on Mutans Streptococci Count: A Randomized, Double Blind, Clinical Study

    Directory of Open Access Journals (Sweden)

    Asif Yousuf

    2016-03-01

    Full Text Available Objectives: Probiotic approaches are being considered to eliminate pathogenic microorganisms and are an alternative and promising way to combat infections by using harmless bacteria to displace pathogenic microorganisms. The aim of this study was to evaluate the effectiveness of commercially available freeze dried powdered probiotics on mutans streptococci count among 12-15 year-old Indian schoolchildren. Materials and Methods: The study was conducted in two phases of in-vitro (phase I and in-vivo (phase II study, which was a double blind, randomized and placebo controlled clinical trial. A total of 33 schoolchildren between 12-15 years were included in the study. They were randomly allocated to three groups. Group A included 11 children using freeze dried Lactobacillus acidophilus, Bifidobacterium longum, Bifidobacterium bifidum and Bifidobacterium lactis. Group B included 11 children using freeze dried lactic acid bacillus only. Group C included 11 children using placebo powder. The study was conducted over a period of three weeks and examination and sampling of the subjects were done on days 0 (baseline, seven, 14 and 21. Results: For both the intervention groups A and B, statistically significant reduction (P<0.05 in salivary mutans streptococci counts was recorded up to the second week.Conclusion: Oral administration of probiotics showed a short-term effect on reduction of mutans streptococci count and showed a preventive role in caries development.Key words: Probiotics; Viridans Streptococci; Dental Caries.

  13. PD-PK evaluation of freeze-dried atorvastatin calcium-loaded poly-ε-caprolactone nanoparticles.

    Science.gov (United States)

    Ahmed, Iman S; El-Hosary, Rania; Shalaby, Samia; Abd-Rabo, Marwa M; Elkhateeb, Dalia G; Nour, Samia

    2016-05-17

    In this work lyophilized poly-ε-caprolactone nanoparticles (NPs) loaded with atorvastatin calcium (AC) were developed in an attempt to improve the in-vivo performance of AC following oral administration. The individual and combined effects of several formulation variables were previously investigated using step-wise full factorial designs in order to produce optimized AC-NPs with predetermined characteristics including particle size, drug loading capacity, drug release profile and physical stability. Four optimized formulations were further subjected in this work to lyophilization to promote their long-term physical stability and were fully characterized. The pharmacodynamics (PD)/pharmacokinetics (PK) properties of two optimized freeze-dried AC-NPs formulations showing acceptable long-term stability were determined and compared to a marketed AC immediate release tablet (Lipitor(®)) in albino rats. PD results revealed that the two tested formulations were equally effective in reducing low density lipoproteins (LDL) and triglycerides (TG) levels when given in reduced doses compared to Lipitor(®) and showed no adverse effects. PK results, on the other hand, revealed that the two freeze-dried AC-NPs formulations were of significantly lower bioavailability compared to Lipitor(®). Taken together the PD and PK results demonstrate that the improved efficacy obtained at reduced doses from the freeze-dried AC-NPs could be due to increased concentration of AC in the liver rather than in the plasma. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. A novel collagen film with micro-rough surface structure for corneal epithelial repair fabricated by freeze drying technique

    International Nuclear Information System (INIS)

    Liu, Yang; Ren, Li; Wang, Yingjun

    2014-01-01

    Highlights: • Collagen film with micro-rough surface is fabricated by freeze drying technique. • The film has suitable water uptake capability and toughness performance. • The film has good optical performance. • Human corneal epithelial cells studies confirmed the biocompatibility of the film. - Abstract: Corneal epithelial defect is a common disease and keratoplasty is a common treatment method. A collagen film with micro-rough surface was fabricated through a simple freeze drying technique in this study. Compared with the air-dried collagen film (AD-Col), this freeze-dried collagen film (FD-Col) has a more suitable water uptake capability (about 85.5%) and toughness performance. Both of the two films have good optical properties and the luminousness of them is higher than 80%. Besides, the adhesion and proliferation rate of human corneal epithelial cells on the micro-rough surface of FD-Col film is higher than that on the smooth surface of AD-Col film. The results indicate that this FD-Col film may have potential applications for corneal epithelial repair

  15. Effect of chemical stabilizers on the thermostability and infectivity of a representative panel of freeze dried viruses.

    Directory of Open Access Journals (Sweden)

    Boris Pastorino

    Full Text Available As a partner of the European Virus Archive (EVA FP7 project, our laboratory maintains a large collection of freeze-dried viruses. The distribution of these viruses to academic researchers, public health organizations and industry is one major aim of the EVA consortium. It is known that lyophilization requires appropriate stabilizers to prevent inactivation of the virus. However, few studies have investigated the influence of different stabilizers and lyophilization protocols on the thermostability of different viruses. In order to identify optimal lyophilization conditions that will deliver maximum retention of viral infectivity titre, different stabilizer formulations containing trehalose, sorbitol, sucrose or foetal bovine serum were evaluated for their efficacy in stabilizing a representative panel of freeze dried viruses at different storage temperatures (-20°C, +4°C and +20°C for one week, the two latter mimicking suboptimal shipping conditions. The Tissue Culture Infectious Dose 50% (TCID50 assay was used to compare the titres of infectious virus. The results obtained using four relevant and model viruses (enveloped/non enveloped RNA/DNA viruses still serve to improve the freeze drying conditions needed for the development and the distribution of a large virus collection.

  16. A novel collagen film with micro-rough surface structure for corneal epithelial repair fabricated by freeze drying technique

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yang [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 (China); Ren, Li, E-mail: psliren@scut.edu.cn [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 (China); Wang, Yingjun, E-mail: imwangyj@163.com [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 (China)

    2014-05-01

    Highlights: • Collagen film with micro-rough surface is fabricated by freeze drying technique. • The film has suitable water uptake capability and toughness performance. • The film has good optical performance. • Human corneal epithelial cells studies confirmed the biocompatibility of the film. - Abstract: Corneal epithelial defect is a common disease and keratoplasty is a common treatment method. A collagen film with micro-rough surface was fabricated through a simple freeze drying technique in this study. Compared with the air-dried collagen film (AD-Col), this freeze-dried collagen film (FD-Col) has a more suitable water uptake capability (about 85.5%) and toughness performance. Both of the two films have good optical properties and the luminousness of them is higher than 80%. Besides, the adhesion and proliferation rate of human corneal epithelial cells on the micro-rough surface of FD-Col film is higher than that on the smooth surface of AD-Col film. The results indicate that this FD-Col film may have potential applications for corneal epithelial repair.

  17. Response Surface Optimization of Lyoprotectant from Amino Acids and Salts for Bifidobacterium Bifidum During Vacuum Freeze-Drying

    Directory of Open Access Journals (Sweden)

    Qi Kangru

    2017-12-01

    Full Text Available High quality probiotic powder can lay the foundation for the commercial production of functional dairy products. The freeze-drying method was used for the preservation of microorganisms, having a deleterious effect on the microorganisms viability. In order to reduce the damage to probiotics and to improve the survival rate of probiotics during freeze-drying, the Response Surface Methodology (RSM was adopted in this research to optimize lyoprotectant composed of amino acids (glycine, arginine and salts (NaHCO3 and ascorbic acid. Probiotic used was Bifidobacterium bifidum BB01. The regression model (p<0.05 was obtained by Box–Behnken experiment design, indicating this model can evaluate the freeze-drying survival rate of B. bifidum BB01 under different lyoprotectants. The results indicated these concentrations as optimal (in W/V: glycine 4.5%, arginine 5.5%, NaHCO3 0.8% and ascorbic acid 2.3%, respectively. Under these optimal conditions, the survival rate of lyophilized powder of B. bifidum BB01 was significantly increased by 80.9% compared to the control group (6.9±0.62%, the results were agreement with the model prediction value (88.7%.

  18. Microencapsulation of Purified Amylase Enzyme from Pitaya (Hylocereus polyrhizus Peel in Arabic Gum-Chitosan using Freeze Drying

    Directory of Open Access Journals (Sweden)

    Mehrnoush Amid

    2014-03-01

    Full Text Available Amylase is one of the most important enzymes in the world due to its wide application in various industries and biotechnological processes. In this study, amylase enzyme from Hylocereus polyrhizus was encapsulated for the first time in an Arabic gum-chitosan matrix using freeze drying. The encapsulated amylase retained complete biocatalytic activity and exhibited a shift in the optimum temperature and considerable increase in the pH and temperature stabilities compared to the free enzyme. Encapsulation of the enzyme protected the activity in the presence of ionic and non-ionic surfactants and oxidizing agents (H2O2 and enhanced the shelf life. The storage stability of amylase is found to markedly increase after immobilization and the freeze dried amylase exhibited maximum encapsulation efficiency value (96.2% after the encapsulation process. Therefore, the present study demonstrated that the encapsulation of the enzyme in a coating agent using freeze drying is an efficient method to keep the enzyme active and stable until required in industry.

  19. Aerodynamic Droplet Stream Expansion for the Production of Spray Freeze-Dried Powders.

    Science.gov (United States)

    Wanning, Stefan; Süverkrüp, Richard; Lamprecht, Alf

    2017-07-01

    In spray freeze-srying (SFD), a solution is sprayed into a refrigerant medium, frozen, and subsequently sublimation dried, which allows the production of flowable lyophilized powders. SFD allows commonly freeze-dried active pharmaceutical ingredients (e.g., proteins and peptides) to be delivered using new applications such as needle-free injection and nasal or pulmonary drug delivery. In this study, a droplet stream was injected into a vortex of cold gas in order to reduce the risk of droplet collisions and therefore droplet growth before congelation, which adversely affects the particle size distribution. Droplets with initial diameters of about 40-50 μm were frozen quickly in a swirl tube at temperatures around -75°C and volumetric gas flow rates between 17 and 34 L/min. Preliminary studies that were focused on the evaluation of spray cone footprints were performed prior to SFD. A 2 3 factorial design with a model solution of mannitol (1.5% m/V) and maltodextrin (1.5% m/V) was used to create flowable, low density (0.01-0.03 g/cm 3 ) spherical lyophilisate powders. Mean particle diameter sizes of the highly porous particles ranged between 49.8 ± 6.6 and 88.3 ± 5.5 μm. Under optimal conditions, the mean particle size was reduced from 160 to 50 μm (decrease of volume by 96%) compared to non-expanded streams, whereas the SPAN value did not change significantly. This method is suitable for the production of lyophilized powders with small particle sizes and narrow particle size distributions, which is highly interesting for needle-free injection or nasal delivery of proteins and peptides.

  20. The effects of freeze-dried Ganoderma lucidum mycelia on a recurrent oral ulceration rat model.

    Science.gov (United States)

    Xie, Ling; Zhong, Xiaohong; Liu, Dongbo; Liu, Lin; Xia, Zhilan

    2017-12-01

    Conventional scientific studies had supported the use of polysaccharides and β-glucans from a number of fungi, including Ganoderma lucidum for the treatment of recurrent oral ulceration (ROU). Our aim of the present study was to evaluate whether freeze-dried powder from G. lucidum mycelia (FDPGLM) prevents ROU in rats. A Sprague-Dawley (SD) rat model with ROU was established by autoantigen injection. The ROU rats were treated with three different dosages of FDPGLM and prednisone acetate (PA), and their effects were evaluated according to the clinical therapeutic evaluation indices of ROU. High-dose FDPGLM induced significantly prolonged total intervals and a reduction in the number of ulcers and ulcer areas, thereby indicating that the treatment was effective in preventing ROU. Enzyme-linked immunosorbent assay (ELISA) showed that high-dose FDPGLM significantly enhanced the serum transforming growth factor-β1 (TGF-β1) levels, whereas reduced those of interleukin-6 (IL-6) and interleukin-17 (IL-17). Flow cytometry (FCM) showed that the proportion of CD4 + CD25 + Foxp3 + (forkhead box P3) regulatory T cells (Tregs) significantly increased by 1.5-fold in the high-dose FDPGLM group compared to that in the rat model group (P < 0.01). The application of middle- and high-dose FDPGLM also resulted in the upregulation of Foxp3 and downregulation of retinoid-related orphan receptor gamma t(RORγt) mRNA. High-dose FDPGLM possibly plays a role in ROU by promoting CD4 + CD25 + Foxp3 + Treg and inhibiting T helper cell 17 differentiation. This study also shows that FDPGLM may be potentially used as a complementary and alternative medicine treatment scheme for ROU.

  1. Freeze-dried bone allografts sterilized with gamma radiation and the clinical use in harelip

    International Nuclear Information System (INIS)

    Luna Z, D.; Reyes F, M. L.; Diaz M, I.; Cruz A, L. C.; Vazquez R, M. A.

    2010-10-01

    Bone for transplant is part of the musculoskeletal tissue join with fascia lat, tendon, ligament and cartilage. Bone is formed by cells (osteocytes, osteoblasts and osteoclasts) and extracellular matrix formed mainly by collagen and hydroxyapatite, which gives strength and elasticity to the bone. The bone function in the body is to move, support, organs protection, production of blood cells and store minerals. The musculoskeletal tissue is processed in specialized tissue banks using gamma radiation of cobalt-60 for sterilization at 25 kGy doses at very low temperature or at room temperature, getting tissues with high quality for clinical applications in injured patients. The process of the bone for transplants varies depend on the size and the surgeon likes, nevertheless in general the large ones are preserved at low temperature (-80 C), meanwhile the short ones are freeze-dried preserved. The musculoskeletal diseases represent the most common physical incapacity, which affect million of people around the world. Due to the human body has 206 bones, during a bone injury each bone can be replaced or repaired with several devices, in general the surgeon goes to a specialized tissue banks, to get the bone, due to the high bone quantity on the body and the number of bone injuries and diseases, the bone is the most transplanted around the world only behind the blood. The bone can be processed in several sizes and shapes, one of these is bone powder from allograft, which is used over all for bone filling, this can be take advantage for cleft lip and palate defects, which is a birth defect, this can affect the way the child's face looks, it can also lead to problems with eating, talking and ear infections. The description of the bone powder process is presented and the clinical use of this powder in several pediatric patients for cleft lip and palate defects is described. (Author)

  2. Freeze-dried bone allografts sterilized with gamma radiation and the clinical use in harelip

    Energy Technology Data Exchange (ETDEWEB)

    Luna Z, D.; Reyes F, M. L. [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico); Diaz M, I.; Cruz A, L. C. [Centro Estatal de Trasplantes del Estado de Mexico, Pablo Sidar No. 602, Col. Universidad, Toluca 50130, Estado de Mexico (Mexico); Vazquez R, M. A., E-mail: daniel.luna@inin.gob.m [Centro de Especialidades Odontologicas, Instituto Materno Infantil del Estado de Mexico, Paseo Colon esquina Felipe Angeles s/n, Col. Villa Hogar, Toluca 50170, Estado de Mexico (Mexico)

    2010-10-15

    Bone for transplant is part of the musculoskeletal tissue join with fascia lat, tendon, ligament and cartilage. Bone is formed by cells (osteocytes, osteoblasts and osteoclasts) and extracellular matrix formed mainly by collagen and hydroxyapatite, which gives strength and elasticity to the bone. The bone function in the body is to move, support, organs protection, production of blood cells and store minerals. The musculoskeletal tissue is processed in specialized tissue banks using gamma radiation of cobalt-60 for sterilization at 25 kGy doses at very low temperature or at room temperature, getting tissues with high quality for clinical applications in injured patients. The process of the bone for transplants varies depend on the size and the surgeon likes, nevertheless in general the large ones are preserved at low temperature (-80 C), meanwhile the short ones are freeze-dried preserved. The musculoskeletal diseases represent the most common physical incapacity, which affect million of people around the world. Due to the human body has 206 bones, during a bone injury each bone can be replaced or repaired with several devices, in general the surgeon goes to a specialized tissue banks, to get the bone, due to the high bone quantity on the body and the number of bone injuries and diseases, the bone is the most transplanted around the world only behind the blood. The bone can be processed in several sizes and shapes, one of these is bone powder from allograft, which is used over all for bone filling, this can be take advantage for cleft lip and palate defects, which is a birth defect, this can affect the way the child's face looks, it can also lead to problems with eating, talking and ear infections. The description of the bone powder process is presented and the clinical use of this powder in several pediatric patients for cleft lip and palate defects is described. (Author)

  3. Controlled ice nucleation using freeze-dried Pseudomonas syringae encapsulated in alginate beads.

    Science.gov (United States)

    Weng, Lindong; Tessier, Shannon N; Swei, Anisa; Stott, Shannon L; Toner, Mehmet

    2017-04-01

    The control of ice nucleation is of fundamental significance in many process technologies related to food and pharmaceutical science and cryobiology. Mechanical perturbation, electromagnetic fields and ice-nucleating agents (INAs) have been known to induce ice nucleation in a controlled manner. But these ice-nucleating methods may suffer from cumbersome manual operations, safety concerns of external fields, and biocompatibility and recovery issues of INA particles, especially when used in living systems. Given the automatic ice-seeding nature of INAs, a promising solution to overcome some of the above limitations is to engineer a biocomposite that accommodates the INA particles but minimizes their interactions with biologics, as well as enabling the recovery of used particles. In this study, freeze-dried Pseudomonas syringae, a model ice-nucleating agent, was encapsulated into microliter-sized alginate beads. We evaluated the performance of the bacterial hydrogel beads to initiate ice nucleation in water and aqueous glycerol solution by investigating factors including the size and number of the beads and the local concentration of INA particles. In the aqueous sample of a fixed volume, the total mass of the INA particles (m) was found to be the governing parameter that is solely responsible for determining the ice nucleation performance of the bacterial hydrogel beads. The freezing temperature has a strong positive linear correlation with log 10 m. The findings in this study provide an effective, predictable approach to control ice nucleation, which can improve the outcome and standardization of many ice-assisted process technologies. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Sterilization of freeze dried manila clam (Ruditapea philippinarum) porridge for immuno-compromised patients

    Energy Technology Data Exchange (ETDEWEB)

    Song, Beom Seok; Park, Jae Nam [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2017-02-15

    This study was conducted to evaluate the combined effect of gamma irradiation and different conditions (vacuum packaging, antioxidant and freezing) on the microbiological and sensory characteristics of freeze dried Manila clam porridge (MCP) for immuno-compromised patient food. McP can be sterilized at 1 kGy to 10 kGy. the initial counts of total aerobic bacteria and yeast molds in the non-irradiated MCP were 2.4±0.5 and 1.2±0.3 log CFU g{sup -}'1, respectively, but gamma irradiation significantly decreased the total aerobic bacteria to below the detection limit (1 log CFU g{sup -1}) (5 kGy). Moreover, gamma irradiation effectively eliminated yeasts/molds at dose below than 1 kGy. However, gamma irradiation accelerated the increase of lipid oxidation and therefore, decreased the sensory characteristics of MCP as irradiation dose increased. to improve the sensory qualities of gamma irradiated MCP, combination treatment (vacuum packaging, 0.1% vitamin c) were applied. there was no significant difference in the overall acceptance scores between the combined-treatment sample (5.6 points) and the non-irradiated samples (6.0). the results indicate that combination treatment (vacuum packaging, 0.1% vitamin c) may help to maintain the quality of MCP. therefore, it considered that irradiation of MCP with combined treatment and this is an effective method for the consumption as a special purpose food such as for space travel or immuno-compromised patients.

  5. Preparation of Chitosan Nanocompositeswith a Macroporous Structure by Unidirectional Freezing and Subsequent Freeze-Drying

    Directory of Open Access Journals (Sweden)

    Inmaculada Aranaz

    2014-11-01

    Full Text Available Chitosan is the N-deacetylated derivative of chitin, a naturally abundant mucopolysaccharide that consists of 2-acetamido-2-deoxy-β-d-glucose through a β (1→4 linkage and is found in nature as the supporting material of crustaceans, insects, etc. Chitosan has been strongly recommended as a suitable functional material because of its excellent biocompatibility, biodegradability, non-toxicity, and adsorption properties. Boosting all these excellent properties to obtain unprecedented performances requires the core competences of materials chemists to design and develop novel processing strategies that ultimately allow tailoring the structure and/or the composition of the resulting chitosan-based materials. For instance, the preparation of macroporous materials is challenging in catalysis, biocatalysis and biomedicine, because the resulting materials will offer a desirable combination of high internal reactive surface area and straightforward molecular transport through broad “highways” leading to such a surface. Moreover, chitosan-based composites made of two or more distinct components will produce structural or functional properties not present in materials composed of one single component. Our group has been working lately on cryogenic processes based on the unidirectional freezing of water slurries and/or hydrogels, the subsequent freeze-drying of which produce macroporous materials with a well-patterned structure. We have applied this process to different gels and colloidal suspensions of inorganic, organic, and hybrid materials. In this review, we will describe the application of the process to chitosan solutions and gels typically containing a second component (e.g., metal and ceramic nanoparticles, or carbon nanotubes for the formation of chitosan nanocomposites with a macroporous structure. We will also discuss the role played by this tailored composition and structure in the ultimate performance of these materials.

  6. Retention of metabolized antimony, cobalt, iodine, mercury, selenium and zinc in various tissues of the rat following freeze-drying and oven-drying at different temperatures

    International Nuclear Information System (INIS)

    Iyengar, G.V.; Kasperek, K.; Feinendegen, L.E.

    1977-01-01

    Loss of Sb, Co, I, Hg, Se, and Zn during freeze-drying and oven-drying at 80 0 C, 105 0 C, and 120 0 C were studied in rat tissues that contained metabolized radioactive isotopes. No loss was observed for any of the 6 elements on freeze-drying. However, tissue-specific differences were observed in many cases for the elements Hg, Se, I, and Sb on oven-drying. Although the losses were statistically significant, they remained in most cases between 2 and 10%, with the exception of Hg at 120 0 C, where the losses in some of the tissues were unpredictable. With respect to urine, freeze-drying and oven-drying at 80 0 C were found to be relatively safe for the elements Hg and I. At 105 0 C and above, serious loss of Hg was observed. For Se only freeze-drying was found to be safe

  7. The impact of freeze-drying infant fecal samples on measures of their bacterial community profiles and milk-derived oligosaccharide content.

    Science.gov (United States)

    Lewis, Zachery T; Davis, Jasmine C C; Smilowitz, Jennifer T; German, J Bruce; Lebrilla, Carlito B; Mills, David A

    2016-01-01

    Infant fecal samples are commonly studied to investigate the impacts of breastfeeding on the development of the microbiota and subsequent health effects. Comparisons of infants living in different geographic regions and environmental contexts are needed to aid our understanding of evolutionarily-selected milk adaptations. However, the preservation of fecal samples from individuals in remote locales until they can be processed can be a challenge. Freeze-drying (lyophilization) offers a cost-effective way to preserve some biological samples for transport and analysis at a later date. Currently, it is unknown what, if any, biases are introduced into various analyses by the freeze-drying process. Here, we investigated how freeze-drying affected analysis of two relevant and intertwined aspects of infant fecal samples, marker gene amplicon sequencing of the bacterial community and the fecal oligosaccharide profile (undigested human milk oligosaccharides). No differences were discovered between the fecal oligosaccharide profiles of wet and freeze-dried samples. The marker gene sequencing data showed an increase in proportional representation of Bacteriodes and a decrease in detection of bifidobacteria and members of class Bacilli after freeze-drying. This sample treatment bias may possibly be related to the cell morphology of these different taxa (Gram status). However, these effects did not overwhelm the natural variation among individuals, as the community data still strongly grouped by subject and not by freeze-drying status. We also found that compensating for sample concentration during freeze-drying, while not necessary, was also not detrimental. Freeze-drying may therefore be an acceptable method of sample preservation and mass reduction for some studies of microbial ecology and milk glycan analysis.

  8. Bulk Freeze-Drying Milling: a Versatile Method of Developing Highly Porous Cushioning Excipients for Compacted Multiple-Unit Pellet Systems (MUPS).

    Science.gov (United States)

    Siow, Carin Ru Shan; Heng, Paul Wan Sia; Chan, Lai Wah

    2018-02-01

    The compaction of multiple-unit pellet system (MUPS) is a challenging process due to the ease of coat damage under high compression pressure, thereby altering drug release rates. To overcome this, cushioning excipients are added to the tablet formulation. Excipients can be processed into pellets/granules and freeze-dried to increase their porosity and cushioning performance. However, successful formation of pellets/granules has specific requirements that limit formulation flexibility. In this study, a novel top-down approach that harnessed bulk freeze-drying milling was explored to avoid the challenges of pelletization/granulation. Aqueous dispersions containing 20%, w/w hydroxypropyl methylcellulose (HPMC), partially pregelatinised starch or polyvinylpyrrolidone alone, and with lactose (Lac) in 1:1 ratio, were freeze-dried and then milled to obtain particulate excipients for characterization and evaluation of their cushioning performance. This study demonstrated that bulk freeze-drying milling is a versatile method for developing excipients that are porous and directly compressible. The freeze-drying process modified the materials in a unique manner which could impart cushioning properties. Compared to unprocessed excipients, the freeze-dried products generally exhibited better cushioning effects. The drug release profile of drug-loaded pellets compacted with freeze-dried Lac-HPMC excipients was similar to that of the uncompacted drug-loaded pellets (f 2 value = 51.7), indicating excellent cushioning effects. It was proposed that the specific balance of brittle and plastic nature of the freeze-dried Lac-HPMC composite conferred greater protective effect to the drug-loaded pellets, making it advantageous as a cushioning excipient.

  9. The impact of freeze-drying infant fecal samples on measures of their bacterial community profiles and milk-derived oligosaccharide content

    Directory of Open Access Journals (Sweden)

    Zachery T. Lewis

    2016-01-01

    Full Text Available Infant fecal samples are commonly studied to investigate the impacts of breastfeeding on the development of the microbiota and subsequent health effects. Comparisons of infants living in different geographic regions and environmental contexts are needed to aid our understanding of evolutionarily-selected milk adaptations. However, the preservation of fecal samples from individuals in remote locales until they can be processed can be a challenge. Freeze-drying (lyophilization offers a cost-effective way to preserve some biological samples for transport and analysis at a later date. Currently, it is unknown what, if any, biases are introduced into various analyses by the freeze-drying process. Here, we investigated how freeze-drying affected analysis of two relevant and intertwined aspects of infant fecal samples, marker gene amplicon sequencing of the bacterial community and the fecal oligosaccharide profile (undigested human milk oligosaccharides. No differences were discovered between the fecal oligosaccharide profiles of wet and freeze-dried samples. The marker gene sequencing data showed an increase in proportional representation of Bacteriodes and a decrease in detection of bifidobacteria and members of class Bacilli after freeze-drying. This sample treatment bias may possibly be related to the cell morphology of these different taxa (Gram status. However, these effects did not overwhelm the natural variation among individuals, as the community data still strongly grouped by subject and not by freeze-drying status. We also found that compensating for sample concentration during freeze-drying, while not necessary, was also not detrimental. Freeze-drying may therefore be an acceptable method of sample preservation and mass reduction for some studies of microbial ecology and milk glycan analysis.

  10. Particle characterization of poorly water-soluble drugs using a spray freeze drying technique.

    Science.gov (United States)

    Kondo, Masahiro; Niwa, Toshiyuki; Okamoto, Hirokazu; Danjo, Kazumi

    2009-07-01

    A spray freeze drying (SFD) method was developed to prepare the composite particles of poorly water-soluble drug. The aqueous solution dissolved drug and the functional polymer was sprayed directly into liquid nitrogen. Then, the iced droplets were lyophilized with freeze-dryer to prepare solid particles. Tolbutamide (TBM) and hydroxypropylmethylcellulose (HPMC) were used as a model drug and water-soluble polymeric carrier in this study, respectively. The morphological observation of particles revealed that the spherical particles having porous structure could be obtained by optimizing the loading amount of drug and polymer in the spray solution. Especially, SFD method was characterized that the prepared particles had significantly larger specific surface area comparing with those prepared by the standard spray drying technique. The physicochemical properties of the resultant particles were found to be dependent on the concentration of spray solution. When the solution with high content of drug and polymer was used, the particle size of the resulting composite particles increased and they became spherical. The specific surface area of the particles also increased as a result of higher concentration of solution. The evaluation of spray solution indicated that these results were dependent on the viscosity of spray solution. In addition, when composite particles of TBM were prepared using the SFD method with HPMC as a carrier, the crystallinity of TBM decreased as the proportion of HPMC increased. When the TBM : HPMC ratio reached 1 : 5, the crystallinity of the particles completely disappeared. The dissolution tests showed that the release profiles of poorly water-soluble TBM from SFD composite particles were drastically improved compared to bulk TBM. The 70% release time T(70) of composite particles prepared by the SFD method in a solution of pH 1.2 was quite smaller than that of bulk TBM, while in a solution of pH 6.8, it was slightly lower. In addition, the

  11. Immunisation of Sheep with Bovine Viral Diarrhoea Virus, E2 Protein Using a Freeze-Dried Hollow Silica Mesoporous Nanoparticle Formulation.

    Directory of Open Access Journals (Sweden)

    Donna Mahony

    Full Text Available Bovine viral diarrhoea virus 1 (BVDV-1 is arguably the most important viral disease of cattle. It is associated with reproductive, respiratory and chronic diseases in cattle across the world. In this study we have investigated the capacity of the major immunological determinant of BVDV-1, the E2 protein combined with hollow type mesoporous silica nanoparticles with surface amino functionalisation (HMSA, to stimulate immune responses in sheep. The current work also investigated the immunogenicity of the E2 nanoformulation before and after freeze-drying processes. The optimal excipient formulation for freeze-drying of the E2 nanoformulation was determined to be 5% trehalose and 1% glycine. This excipient formulation preserved both the E2 protein integrity and HMSA particle structure. Sheep were immunised three times at three week intervals by subcutaneous injection with 500 μg E2 adsorbed to 6.2 mg HMSA as either a non-freeze-dried or freeze-dried nanoformulation. The capacity of both nanovaccine formulations to generate humoral (antibody and cell-mediated responses in sheep were compared to the responses in sheep immunisation with Opti-E2 (500 μg together with the conventional adjuvant Quil-A (1 mg, a saponin from the Molina tree (Quillaja saponira. The level of the antibody responses detected to both the non-freeze-dried and freeze-dried Opti-E2/HMSA nanoformulations were similar to those obtained for Opti-E2 plus Quil-A, demonstrating the E2 nanoformulations were immunogenic in a large animal, and freeze-drying did not affect the immunogenicity of the E2 antigen. Importantly, it was demonstrated that the long term cell-mediated immune responses were detectable up to four months after immunisation. The cell-mediated immune responses were consistently high in all sheep immunised with the freeze-dried Opti-E2/HMSA nanovaccine formulation (>2,290 SFU/million cells compared to the non-freeze-dried nanovaccine formulation (213-500 SFU/million cells

  12. Fabrication and electrical characterization of 15% yttrium-doped barium zirconate-nitrate freeze drying method combined with vacuum heating

    International Nuclear Information System (INIS)

    Imashuku, Susumu; Uda, Tetsuya; Nose, Yoshitaro; Awakura, Yasuhiro

    2011-01-01

    Research highlights: → Very fine 15% yttrium-doped barium zirconate powder of particle size about 30 nm was obtained by synthesizing at 500 deg. C in vacuum from powder mixed by the nitrate freeze-drying method. → Large and homogeneous grains of 15% yttrium-doped barium zirconate were easily obtained using the synthesized powder. → Grain boundary resistance was not inversely proportional to the grain size as theoretically expected. → Specific grain boundary conductivity varies with samples because impurities and/or evaporation loss of barium oxide might affect the grain-boundary resistance in 15% yttrium-doped barium zirconate. - Abstract: We applied a nitrate freeze-drying method to obtain a fine synthesized powder of 15% yttrium-doped barium zirconate. Fine 15% yttrium-doped barium zirconate powder of particle size about 30 nm was obtained by synthesizing at 500 deg. C in vacuum from a powder mixed by the nitrate freeze-drying method. However, we could not obtain such fine powder by synthesizing in air. Using the powder synthesized in vacuum, large and homogeneous grains of 15% yttrium-doped barium zirconate were easily obtained after sintering. Then, the bulk and grain boundary resistance were evaluated by AC 2-terminal measurement of sample in the form of bar and pellet and DC 4-terminal measurement of bar-shape sample. The grain boundary resistance was not inversely proportional to the grain size as theoretically expected. We concluded that specific grain boundary conductivity varies with samples. Some impurities, evaporation loss of barium oxide and/or other unexpected reasons might affect the grain boundary resistance in 15% yttrium-doped barium zirconate.

  13. Comparative Effectiveness of Bone Grafting Using Xenograft Freeze-Dried Cortical Bovine, Allograft Freeze-Dried Cortical New Zealand White Rabbit, Xenograft Hydroxyapatite Bovine, and Xenograft Demineralized Bone Matrix Bovine in Bone Defect of Femoral Diaphysis of White Rabbit: Experimental Study In Vivo

    Directory of Open Access Journals (Sweden)

    Ferdiansyah Mahyudin

    2017-01-01

    Full Text Available Autogenous bone graft is gold standard in treating bone defects, but it might have difficulty in corporation and rejection reaction. This study is to compare the effectiveness among freeze-dried xenograft, freeze-dried allograft, hydroxyapatite xenograft, and demineralized bone matrix xenograft as bone graft to fill bone defect in femoral diaphysis of white rabbit. Thirty male New Zealand white rabbits were distributed into five groups. Bone defect was filled correspondingly with xenograft freeze-dried cortical bovine, allograft freeze-dried cortical New Zealand white rabbit, xenograft hydroxyapatite bovine, and xenograft demineralized bone matrix bovine. No graft was used in control group. VEGF, osteoblast, and woven bone were higher in allograft freeze-dried cortical New Zealand white rabbit (mean 5.6625 (p<0.05 and xenograft demineralized bone matrix bovine (mean 5.2475 (p<0.05 with calcification of woven bone was already seen in week 2 in the latter group. There was a decrease of woven bone (mean 4.685 (p<0.05 fibrous tissue (mean 41.07 (p<0.05 in xenograft demineralized bone matrix bovine. The Immunoglobulin-G was elevated in control and all study groups but not significantly (p=0.07855. Bone healing process in xenograft demineralized bone matrix bovine is more effective than in xenograft hydroxyapatite bovine, allograft freeze-dried New Zealand white rabbit, xenograft freeze-dried cortical bovine, and control.

  14. Optimization of a pharmaceutical freeze-dried product and its process using an experimental design approach and innovative process analyzers.

    Science.gov (United States)

    De Beer, T R M; Wiggenhorn, M; Hawe, A; Kasper, J C; Almeida, A; Quinten, T; Friess, W; Winter, G; Vervaet, C; Remon, J P

    2011-02-15

    The aim of the present study was to examine the possibilities/advantages of using recently introduced in-line spectroscopic process analyzers (Raman, NIR and plasma emission spectroscopy), within well-designed experiments, for the optimization of a pharmaceutical formulation and its freeze-drying process. The formulation under investigation was a mannitol (crystalline bulking agent)-sucrose (lyo- and cryoprotector) excipient system. The effects of two formulation variables (mannitol/sucrose ratio and amount of NaCl) and three process variables (freezing rate, annealing temperature and secondary drying temperature) upon several critical process and product responses (onset and duration of ice crystallization, onset and duration of mannitol crystallization, duration of primary drying, residual moisture content and amount of mannitol hemi-hydrate in end product) were examined using a design of experiments (DOE) methodology. A 2-level fractional factorial design (2(5-1)=16 experiments+3 center points=19 experiments) was employed. All experiments were monitored in-line using Raman, NIR and plasma emission spectroscopy, which supply continuous process and product information during freeze-drying. Off-line X-ray powder diffraction analysis and Karl-Fisher titration were performed to determine the morphology and residual moisture content of the end product, respectively. In first instance, the results showed that - besides the previous described findings in De Beer et al., Anal. Chem. 81 (2009) 7639-7649 - Raman and NIR spectroscopy are able to monitor the product behavior throughout the complete annealing step during freeze-drying. The DOE approach allowed predicting the optimum combination of process and formulation parameters leading to the desired responses. Applying a mannitol/sucrose ratio of 4, without adding NaCl and processing the formulation without an annealing step, using a freezing rate of 0.9°C/min and a secondary drying temperature of 40°C resulted in

  15. NaCl stress impact on the key enzymes in glycolysis from Lactobacillus bulgaricus during freeze-drying.

    Science.gov (United States)

    Li, Chun; Sun, Jinwei; Qi, Xiaoxi; Liu, Libo

    2015-01-01

    The viability of Lactobacillus bulgaricus in freeze-drying is of significant commercial interest to dairy industries. In the study, L.bulgaricus demonstrated a significantly improved (p bulgaricus, the activities and corresponding genes of key enzymes in glycolysis during 2% NaCl stress were studied. NaCl stress significantly enhanced (p bulgaricus under NaCl stress might be due to changes in only the activity or translation level of these enzymes in different environmental conditions but have no relation to their mRNA transcription level.

  16. Freeze drying of red blood cells: the use of directional freezing and a new radio frequency lyophilization device.

    Science.gov (United States)

    Arav, Amir; Natan, Dity

    2012-08-01

    Red blood cell (RBC) units are administered routinely into patients expressing a wide range of acute and chronic conditions (e.g., anemia, traumatic bleeding, chronic diseases, and surgery). The modern blood banking system has been designed to answer this need and assure a continuous, high quality blood supply to patients. However, RBCs units can be stored under hypothermic conditions for only up to 42 days, which leads to periodic shortages. Cryopreservation can solve these shortages, but current freezing methods employ high glycerol concentrations, which need to be removed and the cells washed prior to transfusion, resulting in a long (more than 1 hour) and cumbersome washing step. Thus, frozen RBCs have limited use in acute and trauma situations. In addition, transportation of frozen samples is complicated and costly. Freeze drying (lyophilization) of RBCs has been suggested as a solution for these problems, since it will allow for a low weight sample to be stored at room temperature, but reaching this goal is not a simple task. We studied the effect of different solutions (IMT2 and IMT3) containing trehalose and antioxidants or trehalose and human serum albumin, respectively, on freezing/thawing and freeze drying of RBCs. In addition, we evaluated the effect of cells concentrations and cooling rates on the post thaw and post rehydration recoveries of the RBCs. Finally, we developed a new radio frequency (RF) lyophilization device for a more rapid and homogeneous sublimation process of the frozen RBCs samples. Recovery and free Hb were measured as well as oxygen association/dissociation and cell's deformability. We found that IMT3 (0.3 M trehalose and 10% HSA) solution that was directionally frozen at a rapid interface velocity of 1 mm/sec (resulting in a cooling rate of 150°C/min) yielded the best results (better than IMT2 solution and slow interface velocity). Freeze thawing gave 100% survival, while freeze drying followed by rehydration with 20% dextran-40k

  17. Viability of L. casei during fermentation in soymilk and freeze-dried soymilk; effect of cryoprotectant, rehydration and storage temperature

    Directory of Open Access Journals (Sweden)

    Kristina Mladenovska

    2005-12-01

    Full Text Available The aim of the work was to investigate the behaviour of L. casei and the effect of sorbitol on its viability during fermentation in soymilk drink. Values for pH, ranging from 6.82 to 3.42 in the soymilk drink without sorbitol and from 6.74 to 3.41 in the drink with sorbitol were noted during 72 h of fermentation at 25oC. The corresponding values for titratable acidity ranged from 0.071% to 0.758% and from 0.073% to 0.761%, respectively. Soymilk was found to support the growth of L. casei with improvement in viability for 0.24 log at the end of fermentation when sorbitol was added. Survival of L. casei and the effectiveness of sorbitol in improving viability during freeze-drying, subsequent rehydration and during a 5-week period of storage under different temperatures were also investigated. After freeze-drying, L. casei exhibited a survival percent of approximately 46%. Sorbitol improved the viability of L. casei by 0.51 log immediately after freeze-drying and by 1.30 log and 0.47 log during five weeks of storage at 25oC and 4oC, respectively. Further study revealed that the freeze-dried fermented soymilk rehydrated at 45oC was optimum for the recovery of L. casei with improvement in recovery for 0.68 log when sorbitol was added. A higher percent of survival was noted when the dried soymilk was stored at 4oC than at 25oC with improved viability at the end of 5 weeks storage for approximately 6 log for drinks with and without sorbitol. Fermented dried soymilk with sorbitol afforded significant tolerance of L. casei to acid stress. Generally, a stable probiotic diary product was prepared in which the concentration of L. casei remained above therapeutic level of 107 cfu/ml.

  18. Factors affecting the stability and biodistribution of 99m Tc labelled Sn-pyrophosphate freeze dried kits in normal mice

    International Nuclear Information System (INIS)

    Elkolaly, M.T.; Elwatery, A.S.; Elghany, E.A.

    1995-01-01

    The present study has shown that about 5% of Sn (II) in 99m Tc labelled Sn-pyrophosphate (Sn-PYP) freeze dried kit was oxidized during kit formulation. Also, γ-irradiation doses of 25 and 50 KGy led to Sn (II) losses of about 9.8 and 27.7%, respectively. In-vitro stability and radiochemical purity were biologically confirmed in mice and a high quality scan was achieved on waiting for 3 hours after injection. 3 figs., 6 tabs

  19. Impact of fermentation pH and temperature on freeze-drying survival and membrane lipid composition of Lactobacillus coryniformis Si3.

    Science.gov (United States)

    Schoug, Asa; Fischer, Janett; Heipieper, Hermann J; Schnürer, Johan; Håkansson, Sebastian

    2008-03-01

    During the industrial stabilization process, lactic acid bacteria are subjected to several stressful conditions. Tolerance to dehydration differs among lactic acid bacteria and the determining factors remain largely unknown. Lactobacillus coryniformis Si3 prevents spoilage by mold due to production of acids and specific antifungal compounds. This strain could be added as a biopreservative in feed systems, e.g. silage. We studied the survival of Lb. coryniformis Si3 after freeze-drying in a 10% skim milk and 5% sucrose formulation following different fermentation pH values and temperatures. Initially, a response surface methodology was employed to optimize final cell density and growth rate. At optimal pH and temperature (pH 5.5 and 34 degrees C), the freeze-drying survival of Lb. coryniformis Si3 was 67% (+/-6%). The influence of temperature or pH stress in late logarithmic phase was dependent upon the nature of the stress applied. Heat stress (42 degrees C) did not influence freeze-drying survival, whereas mild cold- (26 degrees C), base- (pH 6.5), and acid- (pH 4.5) stress significantly reduced survival. Freeze-drying survival rates varied fourfold, with the lowest survival following mild cold stress (26 degrees C) prior to freeze-drying and the highest survival after optimal growth or after mild heat (42 degrees C) stress. Levels of different membrane fatty acids were analyzed to determine the adaptive response in this strain. Fatty acids changed with altered fermentation conditions and the degree of membrane lipid saturation decreased when the cells were subjected to stress. This study shows the importance of selecting appropriate fermentation conditions to maximize freeze-drying viability of Lb. coryniformis as well as the effects of various unfavorable conditions during growth on freeze-drying survival.

  20. Application of the Quality by Design Approach to the Freezing Step of Freeze-Drying: Building the Design Space.

    Science.gov (United States)

    Arsiccio, Andrea; Pisano, Roberto

    2018-02-09

    The present work shows a rational method for the development of the freezing step of a freeze-drying cycle. The current approach to the selection of freezing conditions is still empirical and non-systematic, thus resulting in poor robustness of control strategy. The final aim of this work is to fill this gap, describing a rational procedure, based on mathematical modelling, for properly choosing the freezing conditions. Mechanistic models are used for the prediction of temperature profiles during freezing and dimension of ice crystals being formed. Mathematical description of the drying phase of freeze-drying is also coupled with results obtained by freezing models, thus providing a comprehensive characterization of the lyophilization process. In this framework, deep understanding of the phenomena involved is required, and, according to the Quality by Design approach, this knowledge can be used to build the design space. The step by step procedure for building the design space for freezing is thus described and examples of applications are provided. The calculated design space is validated upon experimental data and we show that it allows easy control of the freezing process and fast selection of appropriate operating conditions. Copyright © 2018. Published by Elsevier Inc.

  1. Novel Budesonide Particles for Dry Powder Inhalation Prepared Using a Microfluidic Reactor Coupled With Ultrasonic Spray Freeze Drying.

    Science.gov (United States)

    Saboti, Denis; Maver, Uroš; Chan, Hak-Kim; Planinšek, Odon

    2017-07-01

    Budesonide (BDS) is a potent active pharmaceutical ingredient, often administered using respiratory devices such as metered dose inhalers, nebulizers, and dry powder inhalers. Inhalable drug particles are conventionally produced by crystallization followed by milling. This approach tends to generate partially amorphous materials that require post-processing to improve the formulations' stability. Other methods involve homogenization or precipitation and often require the use of stabilizers, mostly surfactants. The purpose of this study was therefore to develop a novel method for preparation of fine BDS particles using a microfluidic reactor coupled with ultrasonic spray freeze drying, and hence avoiding the need of additional homogenization or stabilizer use. A T-junction microfluidic reactor was employed to produce particle suspension (using an ethanol-water, methanol-water, and an acetone-water system), which was directly fed into an ultrasonic atomization probe, followed by direct feeding to liquid nitrogen. Freeze drying was the final preparation step. The result was fine crystalline BDS powders which, when blended with lactose and dispersed in an Aerolizer at 100 L/min, generated fine particle fraction in the range 47.6% ± 2.8% to 54.9% ± 1.8%, thus exhibiting a good aerosol performance. Subsequent sample analysis confirmed the suitability of the developed method to produce inhalable drug particles without additional homogenization or stabilizers. The developed method provides a viable solution for particle isolation in microfluidics in general. Copyright © 2017 American Pharmacists Association®. All rights reserved.

  2. Bioactivity of freeze-dried platelet-rich plasma in an adsorbed form on a biodegradable polymer material.

    Science.gov (United States)

    Nakajima, Yu; Kawase, Tomoyuki; Kobayashi, Mito; Okuda, Kazuhiro; Wolff, Larry F; Yoshie, Hiromasa

    2012-01-01

    Owing to the necessity for the immediate preparation from patients' blood, autologous platelet-rich plasma (PRP) limits its clinical applicability. To address this concern and respond to emergency care and other unpredictable uses, we have developed a freeze-dried PRP in an adsorbed form on a biodegradable polymer material (Polyglactin 910). On the polymer filaments of PRP mesh, which was prepared by coating the polymer mesh with human fresh PRP and subsequent freeze-drying, platelets were incorporated, and related growth factors were preserved at high levels. This new PRP mesh preparation significantly and reproducibly stimulated the proliferation of human periodontal ligament cells in vitro and neovascularization in a chorioallantoic membrane assay. A full-thickness skin defect model in a diabetic mouse demonstrated the PRP mesh, although prepared from human blood, substantially facilitated angiogenesis, granulation tissue formation, and re-epithelialization without inducing severe inflammation in vivo. These data demonstrate that our new PRP mesh preparation functions as a bioactive material to facilitate tissue repair/regeneration. Therefore, we suggest that this bioactive material, composed of allogeneic PRP, could be clinically used as a promising alternative in emergency care or at times when autologous PRP is not prepared immediately before application.

  3. Quality by design in formulation and process development for a freeze-dried, small molecule parenteral product: a case study.

    Science.gov (United States)

    Mockus, Linas N; Paul, Timothy W; Pease, Nathan A; Harper, Nancy J; Basu, Prabir K; Oslos, Elizabeth A; Sacha, Gregory A; Kuu, Wei Y; Hardwick, Lisa M; Karty, Jacquelyn J; Pikal, Michael J; Hee, Eun; Khan, Mansoor A; Nail, Steven L

    2011-01-01

    A case study has been developed to illustrate one way of incorporating a Quality by Design approach into formulation and process development for a small molecule, freeze-dried parenteral product. Sodium ethacrynate was chosen as the model compound. Principal degradation products of sodium ethacrynate result from hydrolysis of the unsaturated ketone in aqueous solution, and dimer formation from a Diels-Alder condensation in the freeze-dried solid state. When the drug crystallizes in a frozen solution, the eutectic melting temperature is above -5°C. Crystallization in the frozen system is affected by pH in the range of pH 6-8 and buffer concentration in the range of 5-50 mM, where higher pH and lower buffer concentration favor crystallization. Physical state of the drug is critical to solid state stability, given the relative instability of amorphous drug. Stability was shown to vary considerably over the ranges of pH and buffer concentration examined, and vial-to-vial variability in degree of crystallinity is a potential concern. The formulation design space was constructed in terms of pH and drug concentration, and assuming a constant 5 mM concentration of buffer. The process design space is constructed to take into account limitations on the process imposed by the product and by equipment capability.

  4. Effect of physical properties on the stability of Lactobacillus bulgaricus in a freeze-dried galacto-oligosaccharides matrix.

    Science.gov (United States)

    Tymczyszyn, E Elizabeth; Sosa, Natalia; Gerbino, Esteban; Hugo, Ayelen; Gómez-Zavaglia, Andrea; Schebor, Carolina

    2012-04-16

    The ability of galacto-oligosaccharides (GOS) to protect Lactobacillus delbrueckii subsp. bulgaricus upon freeze drying was analyzed on the basis of their capacity to form glassy structures. Glass transition temperatures (T(g)) of a GOS matrix at various relative humidities (RH) were determined by DSC. Survival of L. bulgaricus in a glassy GOS matrix was investigated after freezing, freeze drying, equilibration at different RHs and storage at different temperatures. At 32 °C, a drastic viability loss was observed. At 20 °C, the survival was affected by the water content, having the samples stored at lower RHs, the highest survival percentages. At 4°C, no decay in the cells count was observed after 45 days of storage. The correlation between molecular mobility [as measured by Proton nuclear magnetic resonance (¹H NMR)] and loss of viability explained the efficiency of GOS as cryoprotectants. The preservation of microorganisms was improved at low molecular mobility and this condition was obtained at low water contents and low storage temperatures. These results are important in the developing of new functional foods containing pre and probiotics. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Biofilm-like Lactobacillus rhamnosus probiotics encapsulated in alginate and carrageenan microcapsules exhibiting enhanced thermotolerance and freeze-drying resistance.

    Science.gov (United States)

    Cheow, Wean Sin; Hadinoto, Kunn

    2013-09-09

    Microcapsules containing high-density biofilm-like Lactobacillus rhamnosus probiotics, in place of planktonic cells, are developed in order to enhance the cell viability upon exposures to stresses commonly encountered during food lifecycle (i.e., heating, freeze-drying, refrigerated storage, and acid). The high-density (HD) capsules are prepared by in situ cultivation of the planktonic cells in the confined space of polysaccharide-based capsules (i.e., chitosan-coated alginate and carrageenan capsules). Compared to their planktonic counterparts, the HD capsules exhibit higher freeze-drying resistance (~40×) and higher thermotolerance upon prolonged wet heat exposures at 60 and 70 °C (~12-8000×), but not at higher temperatures even for short exposures (i.e., 80 and 100 °C). The enhanced viability of the HD capsules, however, is not observed during the refrigerated storage and exposure to the simulated gastric juice. The alginate capsules are superior to carrageenan owed to their better cell release profile in the simulated intestinal juice and storage viability.

  6. Effect of amino acids on the stability of spray freeze-dried immunoglobulin G in sugar-based matrices.

    Science.gov (United States)

    Emami, Fakhrossadat; Vatanara, Alireza; Najafabadi, Abdolhosein Rouholamini; Kim, Yejin; Park, Eun Ji; Sardari, Soroush; Na, Dong Hee

    2018-04-09

    The purpose of this study was to prepare spray freeze-dried particles of immunoglobulin G (IgG) using various combinations of trehalose and different amino acids (leucine, phenylalanine, arginine, cysteine, and glycine), and investigate the effect of the amino acids on the stability of IgG during the spray freeze-drying (SFD) process and storage. The morphology and structural integrity of the processed particles were evaluated by physical and spectroscopic techniques. SFD-processed IgG without any excipient resulted in the formation of aggregates corresponding to approximately 14% of IgG. In contrast, IgG formulations stabilized using an optimal level of leucine, phenylalanine, or glycine in the presence of trehalose displayed aggregates <2.2%. In particular, phenylalanine combined with trehalose was most effective in stabilizing IgG against shear, freezing, and dehydration stresses during SFD. Arginine and cysteine were destabilizers displaying aggregation and fragmentation of IgG, respectively. Aggregation and fragmentation were evaluated by dynamic light scattering, ultraviolet spectrophotometry, size-exclusion chromatography, and microchip capillary gel electrophoresis. The IgG formulations prepared with leucine, phenylalanine, or glycine in the presence of trehalose showed good stability after storage at 40 °C and 75% relative humidity for 2 months. Thus, a combination of the excipients trehalose and uncharged, nonpolar amino acids appears effective for production of stable SFD IgG formulations. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Use of a soft sensor for the fast estimation of dried cake resistance during a freeze-drying cycle.

    Science.gov (United States)

    Bosca, Serena; Barresi, Antonello A; Fissore, Davide

    2013-07-15

    This paper deals with the determination of dried cake resistance in a freeze-drying process using the Smart Soft Sensor, a process analytical technology recently proposed by the authors to monitor the primary drying stage of a freeze-drying process. This sensor uses the measurement of product temperature, a mathematical model of the process, and the Kalman filter algorithm to estimate the residual amount of ice in the vial as a function of time, as well as the coefficient of heat transfer between the shelf and the product and the resistance of the dried cake to vapor flow. It does not require expensive (additional) hardware in a freeze-dryer, provided that thermocouples are available. At first, the effect of the insertion of the thermocouple in a vial on the structure of the product is investigated by means of experimental tests, comparing both sublimation rate and cake structure in vials with and without thermocouple. This is required to assess that the temperature measured by the thermocouple is the same of the product in the non-monitored vials, at least in a non-GMP environment, or when controlled nucleation methods are used. Then, results about cake resistance obtained in an extended experimental campaign with aqueous solutions containing different excipients (sucrose, mannitol and polyvinylpyrrolidone), processed in various operating conditions, are presented, with the goal to point out the accuracy of the proposed methodology. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Fast freeze-drying cycle design and optimization using a PAT based on the measurement of product temperature.

    Science.gov (United States)

    Bosca, Serena; Barresi, Antonello A; Fissore, Davide

    2013-10-01

    This paper is focused on the use of an innovative Process Analytical Technology for the fast design and optimization of freeze-drying cycles for pharmaceuticals. The tool is based on a soft-sensor, a device that uses the experimental measure of product temperature during freeze-drying, a mathematical model of the process, and the Extended Kalman Filter algorithm to estimate the sublimation flux, the residual amount of ice in the vial, and some model parameters (heat and mass transfer coefficients). The accuracy of the estimations provided by the soft-sensor has been shown using as test case aqueous solutions containing different excipients (sucrose, polyvinylpyrrolidone), processed at various operating conditions, pointing out that the soft-sensor allows a fast estimation of model parameters and product dynamics without involving expensive hardware or time consuming analysis. The possibility of using the soft-sensor to calculate in-line (or off-line) the design space of the primary drying phase is here presented and discussed. Results evidences that by this way, it is possible to identify the values of the heating fluid temperature that maintain product temperature below the limit value, as well as the operating conditions that maximize the sublimation flux. Various experiments have been carried out to test the effectiveness of the proposed approach for a fast design of the cycle, evidencing that drying time can be significantly reduced, without impairing product quality. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Stability and microstructure of freeze-dried guava pulp (Psidium guajava L.) with added sucrose and pectin.

    Science.gov (United States)

    Conceição, Márcia Cavalcante; Fernandes, Tatiana Nunes; de Resende, Jaime Vilela

    2016-06-01

    Freeze-dried guava pulp powders, formulated with the addition of sucrose (0-20 g/100 g pulp) and pectin (0-1.0 g/100 g pulp), were obtained, and their stability was evaluated with respect to the water adsorption isotherms, thermal analysis and microstructure. The GAB (Guggenheim-Anderson-de Boer), Peleg and BET (Brunauer-Emmett-Teller) models were used to evaluate the water adsorption. The microstructure was examined using optical microscopy with polarized light and scanning electron microscopy (SEM). The GAB and BET parameters showed that the moisture content of the monolayer (Xm) increases with increasing pectin concentration in the adsorption isotherms. Optical microscopy micrographs showed that the pulp consisting of sucrose showed crystalline structures present in a higher amount and size, and this behavior is enhanced with increasing relative moisture. SEM showed that the increase in sucrose and pectin concentrations produced powders with lower porosity, providing greater stability to the product. The glass transition temperature increased slightly with increasing pectin concentration and decreased with increasing moisture content in the guava pulp powder. The kinetic curves, ratio of the increase of the water content against the storage time, of the guava pulp treated with 20 g sucrose per 100 g pulp and higher pectin concentration (0.5 or 1.0 g pectin per 100 g pulp) showed reduced adsorption and yielded freeze-dried pulps that were more stable.

  10. Effect of freeze dried powdered probiotics on gingival status and plaque inhibition: A randomized, double-blind, parallel study

    Directory of Open Access Journals (Sweden)

    Asif Yousuf

    2017-01-01

    Full Text Available Objective: The study aimed to evaluate the effectiveness of freeze dried powdered probiotics on gingival status and plaque inhibition among 12–15-year-old schoolchildren. Materials and Methods: This randomized controlled trial was conducted among 12–15-year-old schoolchildren in Jaipur. Commercially available freeze dried probiotics containing Lactobacillus acidophilus, Bifidobacterium longum, Bifidobacterium bifidum and Bifidobacterium lactis (Prowel, Alkem Laboratories, lactic acid bacillus only (Sporolac, Sangyo, and a placebo powder calcium carbonate 250 g (Calcium Sandoz, Novartis were assigned to two intervention groups and a placebo group each comprising 11 schoolchildren. All subjects were instructed to mix the powder in 30 ml of water and swish once daily for 3 min, for 3 weeks. Periodontal clinical parameters were assessed by examining the subjects for Turesky-Gilmore-Glickman plaque index (PI (Modification of Quigley-Hein PI and gingival index at baseline, 7th day, 14th day, and 21st day. Results: For both the probiotic groups, a statistically significant reduction (P < 0.05 in gingival status and plaque inhibition was recorded up to 2nd week of probiotic ingestion. However, no significant difference was observed in the placebo group. Conclusion: The use of probiotic mouth rinses improves the oral health in children by significantly reducing the plaque and gingival scores. Further studies are warranted to prove or refute the long-term effects, means of administering probiotics and the dosages needed to achieve different preventive or therapeutic purposes.

  11. Application of near infrared spectroscopy in monitoring the moisture content in freeze-drying process of human coagulation factor VIII

    Directory of Open Access Journals (Sweden)

    Fei Wang

    2015-11-01

    Full Text Available As an important process analysis tool, near infrared spectroscopy (NIRS has been widely used in process monitoring. In the present work, the feasibility of NIRS for monitoring the moisture content of human coagulation factor VIII (FVIII in freeze-drying process was investigated. A partial least squares regression (PLS-R model for moisture content determination was built with 88 samples. Different pre-processing methods were explored, and the best method found was standard normal variate (SNV transformation combined with 1st derivation with Savitzky–Golay (SG 15 point smoothing. Then, four different variable selection methods, including uninformative variable elimination (UVE, interval partial least squares regression (iPLS, competitive adaptive reweighted sampling (CARS and manual method, were compared for eliminating irrelevant variables, and iPLS was chosen as the best variable selection method. The correlation coefficient (R, correlation coefficient of calibration set (Rcal, correlation coefficient of validation set (Rval, root mean square errors of cross-validation (RMSECV and root mean square errors of prediction (RMSEP of PLS model were 0.9284, 0.9463, 0.8890, 0.4986% and 0.4514%, respectively. The results showed that the model for moisture content determination has a wide range, good linearity, accuracy and precision. The developed approach was demonstrated to be a potential for monitoring the moisture content of FVIII in freeze-drying process.

  12. Evaluation of Genotoxicity and 28-day Oral Dose Toxicity on Freeze-dried Powder of Tenebrio molitor Larvae (Yellow Mealworm)

    Science.gov (United States)

    Han, So-Ri; Yun, Eun-Young; Kim, Ji-Young; Hwang, Jae Sam; Jeong, Eun Ju

    2014-01-01

    The larval form of Tenebrio molitor (T. molitor) has been eaten in many countries and provides benefits as a new food source of protein for humans. However, no information exists regarding its safety for humans. The objective of the present study was to evaluate the genotoxicity and repeated dose oral toxicity of the freeze-dried powder of T. molitor larvae. The genotoxic potential was evaluated by a standard battery testing: bacterial reverse mutation test, in vitro chromosome aberration test, and in vivo micronucleus test. To assess the repeated dose toxicity, the powder was administered once daily by oral gavage to Sprague-Dawley (SD) rats at dose levels of 0, 300, 1000 and 3000 mg/kg/day for 28 days. The parameters which were applied to the study were mortality, clinical signs, body and organ weights, food consumption, ophthalmology, urinalysis, hematology, serum chemistry, gross findings and histopathologic examination. The freezedried powder of T. molitor larvae was not mutagenic or clastogenic based on results of in vitro and in vivo genotoxicity assays. Furthermore, no treatment-related changes or findings were observed in any parameters in rats after 28 days oral administration. In conclusion, the freeze-dried powder of T. molitor larvae was considered to be non-genotoxic and the NOAEL (No Observed Adverse Effect Level) was determined to be 3000 mg/kg/day in both sexes of SD rats under our experimental conditions. PMID:25071922

  13. Evaluation of Genotoxicity and 28-day Oral Dose Toxicity on Freeze-dried Powder of Tenebrio molitor Larvae (Yellow Mealworm).

    Science.gov (United States)

    Han, So-Ri; Yun, Eun-Young; Kim, Ji-Young; Hwang, Jae Sam; Jeong, Eun Ju; Moon, Kyoung-Sik

    2014-06-01

    The larval form of Tenebrio molitor (T. molitor) has been eaten in many countries and provides benefits as a new food source of protein for humans. However, no information exists regarding its safety for humans. The objective of the present study was to evaluate the genotoxicity and repeated dose oral toxicity of the freeze-dried powder of T. molitor larvae. The genotoxic potential was evaluated by a standard battery testing: bacterial reverse mutation test, in vitro chromosome aberration test, and in vivo micronucleus test. To assess the repeated dose toxicity, the powder was administered once daily by oral gavage to Sprague-Dawley (SD) rats at dose levels of 0, 300, 1000 and 3000 mg/kg/day for 28 days. The parameters which were applied to the study were mortality, clinical signs, body and organ weights, food consumption, ophthalmology, urinalysis, hematology, serum chemistry, gross findings and histopathologic examination. The freezedried powder of T. molitor larvae was not mutagenic or clastogenic based on results of in vitro and in vivo genotoxicity assays. Furthermore, no treatment-related changes or findings were observed in any parameters in rats after 28 days oral administration. In conclusion, the freeze-dried powder of T. molitor larvae was considered to be non-genotoxic and the NOAEL (No Observed Adverse Effect Level) was determined to be 3000 mg/kg/day in both sexes of SD rats under our experimental conditions.

  14. Freeze-drying for sustainable synthesis of nitrogen doped porous carbon cryogel with enhanced supercapacitor and lithium ion storage performance

    International Nuclear Information System (INIS)

    Ling, Zheng; Yu, Chang; Fan, Xiaoming; Liu, Shaohong; Yang, Juan; Zhang, Mengdi; Wang, Gang; Xiao, Nan; Qiu, Jieshan

    2015-01-01

    A chitosan (CS) based nitrogen doped carbon cryogel with a high specific surface area (SSA) has been directly synthesized via a combined process of freeze-drying and high-temperature carbonization without adding any activation agents. The as-made carbon cryogel demonstrates an SSA up to 1025 m 2 g −1 and a high nitrogen content of 5.98 wt%, while its counterpart derived from CS powder only shows an SSA of 26 m 2 g −1 . Freeze-drying is a determining factor for the formation of carbon cryogel with a high SSA, where the CS powder with a size of ca. 200 μm is transformed into the sheet-shaped cryogel with a thickness of 5–8 μm. The as-made carbon cryogel keeps the sheet-shaped structure and the abundant pores are formed in situ and decorated inside the sheets during carbonization. The carbon cryogel shows significantly enhanced performance as supercapacitor and lithium ion battery electrodes in terms of capacity and rate capability due to its quasi two-dimensional (2D) structure with reduced thickness. The proposed method may provide a simple approach to configure 2D biomass-derived advanced carbon materials for energy storage devices. (paper)

  15. Dielectric properties of a BaTiO3 ceramic prepared by using the freeze drying method

    International Nuclear Information System (INIS)

    Al-Shakarchi, Emad K.

    2010-01-01

    A modified catecholate process has been developed to synthesize high-purity barium titanate by using a freeze drying method to produce ultra-fine powders from a barium titanium catechol complex, Ba[Ti(C 6 H 4 O 2 ) 3 ]. The complex prepared from TiCl 4 , C 6 H 4 (OH) 2 and BaCO 3 . The freeze drying of the complex Ba[Ti(C 6 H 4 O 2 ) 3 ] under a primary vacuum at a freezing temperature of -50 .deg. C for a long time 24 hrs is necessary to transfer the complex Ba[Ti(C 6 H 4 O 2 ) 3 ] from a liquid phase to a solid phase. A subsequent calcination of the complex for 12 hrs at a temperature of 700 .deg. C was very important to remove the acetates from the mixture. Finally, a sintering process was required for the pellets so that high density samples could be investigated. The dielectric properties, the structural phase, and the particle size of the sintered pellets have investigated as functions of frequency and temperature in order to determine the critical temperature for the phase transition. X-ray diffraction was used to investigate the structural properties and the particle size. The tetragonal phase of BaTiO 3 with the lattice constants a = b = 3.9734 A, and c = 4.012 A was successfully obtained.

  16. Optimisation of phenolic extraction from Averrhoa carambola pomace by response surface methodology and its microencapsulation by spray and freeze drying.

    Science.gov (United States)

    Saikia, Sangeeta; Mahnot, Nikhil Kumar; Mahanta, Charu Lata

    2015-03-15

    Optimised of the extraction of polyphenol from star fruit (Averrhoa carambola) pomace using response surface methodology was carried out. Two variables viz. temperature (°C) and ethanol concentration (%) with 5 levels (-1.414, -1, 0, +1 and +1.414) were used to design the optimisation model using central composite rotatable design where, -1.414 and +1.414 refer to axial values, -1 and +1 mean factorial points and 0 refers to centre point of the design. The two variables, temperature of 40°C and ethanol concentration of 65% were the optimised conditions for the response variables of total phenolic content, ferric reducing antioxidant capacity and 2,2-diphenyl-1-picrylhydrazyl scavenging activity. The reverse phase-high pressure liquid chromatography chromatogram of the polyphenol extract showed eight phenolic acids and ascorbic acid. The extract was then encapsulated with maltodextrin (⩽ DE 20) by spray and freeze drying methods at three different concentrations. Highest encapsulating efficiency was obtained in freeze dried encapsulates (78-97%). The obtained optimised model could be used for polyphenol extraction from star fruit pomace and microencapsulates can be incorporated in different food systems to enhance their antioxidant property. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Screening of freeze-dried protective agents for the formulation of biocontrol strains, Bacillus cereus AR156, Burkholderia vietnamiensis B418 and Pantoea agglomerans 2Re40.

    Science.gov (United States)

    Zhan, Y; Xu, Q; Yang, M-M; Yang, H-T; Liu, H-X; Wang, Y-P; Guo, J-H

    2012-01-01

    The effects of different freeze-drying protective agents on the viabilities of biocontrol strains Bacillus cereus AR156, Burkholderia vietnamiensis B418 and Pantoea agglomerans 2Re40 were investigated. Several concentrations of protective and rehydration media were tested to improve the survival of biocontrol agents after freeze-drying. The subsequent survival rates during storage and rehydration media of freeze-dried biocontrol strains were also examined. The results indicated that cellobiose (5%) and d-galactose (5%) gave maximum viability of strains Bu. vietnamiensis B418 and P. agglomerans 2Re40 (98 and 54·3% respectively) while the perfect one (100%) of strain B. cereus AR156 was obtained with sucrose (5%) during freeze-drying, and the highest survival of the three strains was reached when they were rehydrated with 10% nonfat skim milk. In the following storage, the survival rates showed that B. cereus AR156 could still reach 50% after 12 months. This study showed that freeze-drying could be used to stabilize cells of these three biocontrol strains. Further studies should focus on the scale-up possibilities and formulation development. © Nanjing Agricultural University. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

  18. Rapid formation of the 110 K phase in Bi-Pb-Sr-Ca-Cu-O through freeze-drying powder processing

    International Nuclear Information System (INIS)

    Song, K.H.; Liu, H.K.; Dou, S.X.; Sorrell, C.C.

    1990-01-01

    This paper reports three techniques for processing Bi-Pb-Sr-Ca-Cu-O (BPSCCO) powders investigated: dry-mixing, sol-gel formation, and freeze-drying. It was found that sintering for 120 h at 850 degrees C is required to form nearly single-phase (Bi,Pb) 2 Sr 2 Ca 2 Cu 3 O 10-y by dry-mixing, whereas sintering for 30 h at 840 degrees C was sufficient to form the 110 K (2223) phase when freeze-drying was used. The sol-gel route was found to be intermediate in efficiency between these two techniques. Freeze-drying provided highly reactive, intimately mixed, and carbon-free precursors. The presence of carbonates in the uncalcined powders was the major cause of phase segregation and sluggishness of the 110 K phase formation

  19. The performance of five fruit-derived and freeze-dried potentially probiotic Lactobacillus strains in apple, orange and grape juices.

    Science.gov (United States)

    Garcia, Estefânia Fernandes; de Oliveira Araújo, Amanda; Luciano, Winnie Alencar; de Albuquerque, Thatyane Mariano Rodrigues; de Oliveira Arcanjo, Narciza Maria; Madruga, Marta Suely; Dos Santos Lima, Marcos; Magnani, Marciane; Saarela, Maria; de Souza, Evandro Leite

    2018-03-30

    This study assessed the survival of the fruit-derived and freeze-dried L. plantarum 49, L. brevis 59, L. paracasei 108, L. fermentum 111 and L. pentosus 129 strains during frozen storage and when incorporated into apple, orange and grape juice stored under refrigeration. Physicochemical parameters of juices containing the freeze-dried Lactobacillus strains and the survival of the test strains in the fruit juices during in vitro digestion were also evaluated. No decreases in survival rates (log N/log N0) of the freeze-dried cells were observed up to 1 month of storage. The survival rates of the freeze-dried strains L. plantarum 49 and L. paracasei 108 were >0.75 up to 4 months of storage. All freeze-dried strains exhibited survival rates of >0.75 up to 2 weeks of storage in apple juice; only L. plantarum 49 and L. paracasei 108 showed similar survival rates in orange and grape juices up to 2 weeks of storage. The contents of the monitored organic acids or sugars during storage varied depending on the added strain and the type of fruit juice. At the end of the in vitro digestion, L. brevis 59, L. paracasei 108 and L. fermentum 111 showed survival rates of >0.80 in apple juice. Apple juice was as the best substrate to the survival of the tested freeze-dried Lactobacillus strains over time. L. paracasei 108 and L. plantarum 49 as the strains presenting the best performance for incorporation in potentially probiotic fruit juices. This article is protected by copyright. All rights reserved.

  20. Cyclopropanation of unsaturated fatty acids and membrane rigidification improve the freeze-drying resistance of Lactococcus lactis subsp. lactis TOMSC161.

    Science.gov (United States)

    Velly, H; Bouix, M; Passot, S; Penicaud, C; Beinsteiner, H; Ghorbal, S; Lieben, P; Fonseca, F

    2015-01-01

    This work aimed at characterizing the biochemical and biophysical properties of the membrane of Lactococcus lactis TOMSC161 cells during fermentation at different temperatures, in relation to their freeze-drying and storage resistance. Cells were cultivated at two different temperatures (22 and 30 °C) and were harvested at different growth phases (from the middle exponential phase to the late stationary phase). Bacterial membranes were characterized by determining the fatty acid composition, the lipid phase transition, and the membrane fluidity. Cultivability and acidification activity losses of L. lactis were quantified after freezing, drying, and 3 months of storage. The direct measurement of membrane fluidity by fluorescence anisotropy was linked to lipid composition, and it was established that the cyclopropanation of unsaturated fatty acids with concomitant membrane rigidification during growth led to an increase in the freeze-drying and storage resistance of L. lactis. As expected, cultivating cells at a lower fermentation temperature than the optimum growth temperature induced a homeoviscous adaptation that was demonstrated by a lowered lipid phase transition temperature but that was not related to any improvement in freeze-drying resistance. L. lactis TOMSC161 was therefore able to develop a combined biochemical and biophysical response at the membrane level during fermentation. The ratio of cyclic fatty acids to unsaturated fatty acids (CFA/UFA) appeared to be the most relevant parameter associated with membrane rigidification and cell resistance to freeze-drying and storage. This study increased our knowledge about the physiological mechanisms that explain the resistance of lactic acid bacteria (LAB) to freeze-drying and storage stresses and demonstrated the relevance of complementary methods of membrane characterization.

  1. Effect of acid whey and freeze-dried cranberries on lipid oxidation and fatty acid composition of nitrite-/nitrate-free fermented sausage made from deer meat

    Directory of Open Access Journals (Sweden)

    Małgorzata Karwowska

    2017-01-01

    Full Text Available Objective This study evaluated the effect of acid whey and freeze-dried cranberries on the physicochemical characteristics, lipid oxidation and fatty acid composition of nitrite-free fermented sausage made from deer meat and pork fat. Antioxidant interactions between acid whey and cranberry compounds were also explored. Methods Four formulations of fermented venison sausage were prepared: F1 (control, F2 (with 5% liquid acid whey, F3 (with 0.06% of freeze-dried cranberries, and F4 (with 5% liquid acid whey and 0.06% of freeze-dried cranberries. Each sample was analyzed for pH, water activity (aw, heme iron content, 2-thiobarbituric acid reactive substances (TBARS value and conjugated dienes at the end of the manufacturing process and at 30 and 90 days of refrigerated storage. Fatty acid composition was measured once at the end of the manufacturing process. Results At the end of ripening, all samples presented statistically different values for a pH range of 4.47 to pH 4.59. The sum of the unsaturated fatty acids was higher, while the conjugated diene and the TBARS values were lower in sausages with freeze-dried cranberries as compared to the control sausage. The highest content of heme iron (21.52 mg/kg at day 90 was found in the sausage formulation with the addition of freeze-dried cranberries, which suggests that the addition of cranberries stabilized the porphyrin ring of the heme molecule during storage and thereby reduced the release of iron. The use of liquid acid whey in combination with cranberries appears to not be justified in view of the oxidative stability of the obtained products. Conclusion The results suggest that the application of freeze-dried cranberries can lower the intensity of oxidative changes during the storage of nitrite-free fermented sausage made from deer meat.

  2. Measurement of water-holding capacity in raw and freeze-dried broiler breast meat with visible and near-infrared spectroscopy.

    Science.gov (United States)

    Bowker, B; Hawkins, S; Zhuang, H

    2014-07-01

    The feasibility of using visible/near-infrared spectroscopy (vis/NIR) to segregate broiler breast fillets by water-holding capacity (WHC) was determined. Broiler breast fillets (n = 72) were selected from a commercial deboning line based on visual color assessment. Meat color (L*a*b*), pH (2 and 24 h), drip loss, and salt-induced water uptake were measured. Reflectance measurements were recorded from 400 to 2,500 nm in both raw and freeze-dried breast meat samples. Raw and freeze-dried samples had similar spectra in the visible region (400-750 nm), but the freeze-dried samples exhibited numerous bands in the NIR region (750-2,500 nm) corresponding to muscle proteins and lipids that were not observed in the NIR spectra of the raw samples. Linear discriminate analyses were used to classify fillets as high-WHC or low-WHC according to predicted meat quality characteristics. Using the visible spectra (400-750 nm), fillets could be correctly classified into high-WHC and low-WHC groups based on drip loss and salt-induced water uptake with 88 to 92% accuracy in raw samples and 79 to 86% accuracy in freeze-dried samples. Using the NIR spectra (750-2,500 nm), fillets could be correctly classified into high-WHC and low-WHC groups with 74 to 76% accuracy in raw samples and 85 to 86% accuracy in freeze-dried samples. Thus, freeze-drying enhanced the accuracy of WHC classification using the NIR portion of the spectra. Data from this study demonstrate the potential for utilizing vis/NIR spectroscopy as a method for classifying broiler breast meat according to WHC. © 2014 Poultry Science Association Inc.

  3. The influence of lysozyme on mannitol polymorphism in freeze-dried and spray-dried formulations depends on the selection of the drying process

    DEFF Research Database (Denmark)

    Grohganz, Holger; Lee, Yan-Ying; Rantanen, Jukka

    2013-01-01

    Freeze-drying and spray-drying are often applied drying techniques for biopharmaceutical formulations. The formation of different solid forms upon drying is often dependent on the complex interplay between excipient selection and process parameters. The purpose of this study was to investigate......-dried formulations an increase in protein concentration resulted in a shift from ß-mannitol to a-mannitol. An increase in final drying temperature of the freeze-drying process towards the temperature of the spray-drying process did not lead to significant changes. It can thus be concluded that it is the drying...

  4. Preparation and optical spectroscopy of Eu3+-doped GaN luminescent semiconductor from freeze-dried precursors

    International Nuclear Information System (INIS)

    El-Himri, Abdelouahad; Perez-Coll, Domingo; Nun-tilde ez, Pedro; Martin, Inocencio R.; Lavin, Victor; Rodriguez, Vicente D.

    2004-01-01

    Pure and 0.5% and 5mol% Eu 3+ doped GaN nanoparticles have been prepared by ammonolysis of the corresponding freeze-dried precursors. A single hexagonal phase with the wurtzite structure was obtained as determined by X-ray Powder Diffraction. The crystallite size determined by XRD was lower than 10nm. From optical spectroscopy characterization, it is found that the Eu 2 O 3 formation is avoided by using nitrates as starting reagent. Fluorescence line narrowing spectra show excitation wavelength dependence, which is indicative that the Eu 3+ ions are well dispersed in the prepared samples. The environment distribution occupied by the Eu 3+ ions has been analyzed by crystal-field calculation and the results are compared with those for other materials

  5. Bilateral maxillary sinus floor augmentation with tissue-engineered autologous osteoblasts and demineralized freeze-dried bone

    Directory of Open Access Journals (Sweden)

    Aashish Deshmukh

    2015-01-01

    Full Text Available The pneumatization of the maxillary sinus often results in a lack of sufficient alveolar bone for implant placement. In the last decades, maxillary sinus lift has become a very popular procedure with predictable results. Sinus floor augmentation procedures are generally carried out using autologous bone grafts, bone substitutes, or composites of bone and bone substitutes. However, the inherent limitations associated with each of these, have directed the attention of investigators to new technologies like bone tissue engineering. Bone marrow stromal cells have been regarded as multi-potent cells residing in bone marrow. These cells can be harvested from a person, multiplied outside his body using bioengineering principles and technologies and later introduced into a tissue defect. We present a case where tissue-engineered autologous osteoblasts were used along with demineralized freeze-dried bone for sinus floor augmentation.

  6. Fabrication of highly porous keratin sponges by freeze-drying in the presence of calcium alginate beads

    International Nuclear Information System (INIS)

    Hamasaki, Shinichi; Tachibana, Akira; Tada, Daisuke; Yamauchi, Kiyoshi; Tanabe, Toshizumi

    2008-01-01

    Novel fabrication method of highly porous and flexible keratin sponges was developed by combining a particulate-leaching method and a freeze-drying method. Reduced keratin aqueous solution was mixed with dried calcium alginate beads and was lyophilized to give keratin/calcium alginate complex, which was subsequently treated with EDTA solution to leach out calcium alginate beads. The resultant keratin sponge was flexible enough to handle even in dried state because of its quite high porosity (98.9 ± 0.1%), which was brought about by the large and small pores formed by the elimination of calcium alginate beads and water. The sponge supported the attachment and the proliferation of mouse fibroblast cells. Thus, the keratin sponge given by the present fabrication method afforded one alternative as a cell scaffold for tissue engineering

  7. Freeze drying synthesis of LiNi0.5Mn0.5O2 cathode materials

    International Nuclear Information System (INIS)

    Shlyakhtin, O.A.; Yoon, Young Soo; Choi, Sun Hee; Oh, Young-Jei

    2004-01-01

    The influence of several processing conditions on the phase formation and electrochemical performance of LiNi 0.5 Mn 0.5 O 2 powders, obtained by freeze drying method, is studied. Thermal processing in pellets at maximum heating rate promotes better crystallographic ordering of hexagonal LiNi 0.5 Mn 0.5 O 2 and maximum capacity values irrespectively of chemical composition of the precursor. Instead, intense mechanical processing of precursors exerts considerable negative effect on the electrochemical performance. Cathode materials containing superstoichiometric amount of lithium (Li 1.3 Mn 0.5 Ni 0.5 O 2+δ ) demonstrate reversible capacity values up to 190 mAh/g between 2.5 and 4.6 V

  8. Process Analytical Technology in Freeze-Drying: Detection of the Secondary Solute + Water Crystallization with Heat Flux Sensors.

    Science.gov (United States)

    Wang, Qiming; Shalaev, Evgenyi

    2017-11-03

    In situ and non-invasive detection of solute crystallization during freeze-drying would facilitate cycle optimization and scale-up from the laboratory to commercial manufacturing scale. The objective of the study is to evaluate heat flux sensor (HFS) as a tool for monitoring solute crystallization and other first-order phase transitions (e.g., onset of freezing). HFS is a thin-film differential thermopile, which acts as a transducer to generate an electrical signal proportional to the total heat applied to its surface. In this study, HFS is used to detect both primary (ice formation) and secondary (also known as eutectic) solute + water crystallization during cooling and heating of solutions in a freeze-dryer. Binary water-solute mixtures with typical excipients concentrations (e.g., 0.9% of NaCl and 5% mannitol) and fill volumes (1 to 3 ml/vial) are studied. Secondary crystallization is detected by the HFS during cooling in all experiments with NaCl solutions, whereas timing of mannitol crystallization depends on the cooling conditions. In particular, mannitol crystallization takes place during cooling, if the cooling rate is lower than the critical value. On the other hand, if the cooling rate exceeds the critical cooling rate, mannitol crystallization during cooling is prevented, and crystallization occurs during subsequent warming or annealing. It is also observed that, while controlled ice nucleation allows initiation of the primary freezing event in different vials simultaneously, there is a noticeable vial-to-vial difference in the timing of secondary crystallization. The HFS could be a valuable process monitoring tool for non-invasive detection of various crystallization events during freeze-drying manufacturing.

  9. Elemental distribution and sample integrity comparison of freeze-dried and frozen-hydrated biological tissue samples with nuclear microprobe

    Energy Technology Data Exchange (ETDEWEB)

    Vavpetič, P., E-mail: primoz.vavpetic@ijs.si [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Vogel-Mikuš, K. [Biotechnical Faculty, Department of Biology, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana (Slovenia); Jeromel, L. [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Ogrinc Potočnik, N. [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); FOM-Institute AMOLF, Science Park 104, 1098 XG Amsterdam (Netherlands); Pongrac, P. [Biotechnical Faculty, Department of Biology, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana (Slovenia); Department of Plant Physiology, University of Bayreuth, Universitätstr. 30, 95447 Bayreuth (Germany); Drobne, D.; Pipan Tkalec, Ž.; Novak, S.; Kos, M.; Koren, Š.; Regvar, M. [Biotechnical Faculty, Department of Biology, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana (Slovenia); Pelicon, P. [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia)

    2015-04-01

    The analysis of biological samples in frozen-hydrated state with micro-PIXE technique at Jožef Stefan Institute (JSI) nuclear microprobe has matured to a point that enables us to measure and examine frozen tissue samples routinely as a standard research method. Cryotome-cut slice of frozen-hydrated biological sample is mounted between two thin foils and positioned on the sample holder. The temperature of the cold stage in the measuring chamber is kept below 130 K throughout the insertion of the samples and the proton beam exposure. Matrix composition of frozen-hydrated tissue is consisted mostly of ice. Sample deterioration during proton beam exposure is monitored during the experiment, as both Elastic Backscattering Spectrometry (EBS) and Scanning Transmission Ion Microscopy (STIM) in on–off axis geometry are recorded together with the events in two PIXE detectors and backscattered ions from the chopper in a single list-mode file. The aim of this experiment was to determine differences and similarities between two kinds of biological sample preparation techniques for micro-PIXE analysis, namely freeze-drying and frozen-hydrated sample preparation in order to evaluate the improvements in the elemental localisation of the latter technique if any. In the presented work, a standard micro-PIXE configuration for tissue mapping at JSI was used with five detection systems operating in parallel, with proton beam cross section of 1.0 × 1.0 μm{sup 2} and a beam current of 100 pA. The comparison of the resulting elemental distributions measured at the biological tissue prepared in the frozen-hydrated and in the freeze-dried state revealed differences in elemental distribution of particular elements at the cellular level due to the morphology alteration in particular tissue compartments induced either by water removal in the lyophilisation process or by unsatisfactory preparation of samples for cutting and mounting during the shock-freezing phase of sample preparation.

  10. Preparation of freeze dried kit of sodium citrate labeled with Tc-99m used as a new kidney functional agent

    International Nuclear Information System (INIS)

    Merzah, K. S.; Abdulkrim, H. M.; Resen, H. M.; Badi, J. M.

    2012-12-01

    A new freeze-dried kit of sodium citrate complex has been prepared, to be labeled with technetium-99m can be used for diagnosis of kidney function. The labeling conditions of Tc-99m citrate complex using stannous chloride as a reducing agent for pertechnetate have been described. The GCS method reveals that the labeling efficiency of Tc-99m citrate complex is promoted by raisinng the pH of the preparation to (pH=4) using 1 N NaOH. The optimal amounts of the reactants in the preparation to obtain labeled and stable complex with high kidney uptake were found to be not less than (1 mg) sodium citrate and not more than (100μg) SnCI 2 2HO. The results show that high labeling yield (≥95%) for the labeled complex (Tc-99 Sn- citrate) can be perform due to the suitable reactant materials. The data of biodistribution experiments in the laboratory animals (Mice), clear high radioactivity accumulation labeled complex in kidney at 5 minutes post injection. The results of the radiochemical purity and biodistribution studies of the lyophilized kit approved that it was stable for about more than seven moths under normal conditions (2-8 o C ). The results of biodistribution of labeled kit have shown a good biological behavior with low radioactivity accumulation in the non-target organs (blood, liver and other organs). the aim of this study was to evaluate the potential of Tc-99-citrate complex as a new kidney functional agents and the efficiency of the freeze dried kit in the diagnosis of kidney function. (Author)

  11. Optimization of packaging and storage conditions of a freeze-dried Pantoea agglomerans formulation for controlling postharvest diseases in fruit.

    Science.gov (United States)

    Torres, R; Solsona, C; Viñas, I; Usall, J; Plaza, P; Teixidó, N

    2014-07-01

    This study aimed to evaluate different packaging strategies to extend the shelf life of a freeze-dried formulation of the biocontrol agent Pantoea agglomerans strain CPA-2. Different materials and atmosphere packaging conditions (vacuum and air) were analysed on formulated P. agglomerans cells stored at 25, 5 and -20°C. Results showed the viability of CPA-2 cells stored at 5 or -20°C was significantly higher than when stored at 25°C. The highest viabilities were observed with the plastic material designated as Bottle 1, in nonvacuum packaging in all storage temperatures: 50% after 3 months at 25°C, 100% after 8 months at 5°C and 100 and 74% after 12 and 18 months, respectively, at -20°C; the final concentration was 10(12) CFU g(-1), a good concentration for a commercial product. The efficacy to control blue and green mould on apples and oranges, respectively, of these packed and stored cells was similar to fresh CPA-2 cells. This work showed a suitable packaging strategy for a freeze-dried formulation of the CPA-2, providing a good shelf life and efficacy against the major postharvest diseases of apples and citrus based on a plastic bottle stored at cold or frozen storage conditions. The last phase of the commercial development process for biocontrol agents is presented in this work. A bacterium-based product that ensures the efficacy, stability and easy application of the antagonist to control postharvest fungal diseases on fruit was successfully obtained. © 2014 The Society for Applied Microbiology.

  12. Elemental distribution and sample integrity comparison of freeze-dried and frozen-hydrated biological tissue samples with nuclear microprobe

    International Nuclear Information System (INIS)

    Vavpetič, P.; Vogel-Mikuš, K.; Jeromel, L.; Ogrinc Potočnik, N.; Pongrac, P.; Drobne, D.; Pipan Tkalec, Ž.; Novak, S.; Kos, M.; Koren, Š.; Regvar, M.; Pelicon, P.

    2015-01-01

    The analysis of biological samples in frozen-hydrated state with micro-PIXE technique at Jožef Stefan Institute (JSI) nuclear microprobe has matured to a point that enables us to measure and examine frozen tissue samples routinely as a standard research method. Cryotome-cut slice of frozen-hydrated biological sample is mounted between two thin foils and positioned on the sample holder. The temperature of the cold stage in the measuring chamber is kept below 130 K throughout the insertion of the samples and the proton beam exposure. Matrix composition of frozen-hydrated tissue is consisted mostly of ice. Sample deterioration during proton beam exposure is monitored during the experiment, as both Elastic Backscattering Spectrometry (EBS) and Scanning Transmission Ion Microscopy (STIM) in on–off axis geometry are recorded together with the events in two PIXE detectors and backscattered ions from the chopper in a single list-mode file. The aim of this experiment was to determine differences and similarities between two kinds of biological sample preparation techniques for micro-PIXE analysis, namely freeze-drying and frozen-hydrated sample preparation in order to evaluate the improvements in the elemental localisation of the latter technique if any. In the presented work, a standard micro-PIXE configuration for tissue mapping at JSI was used with five detection systems operating in parallel, with proton beam cross section of 1.0 × 1.0 μm 2 and a beam current of 100 pA. The comparison of the resulting elemental distributions measured at the biological tissue prepared in the frozen-hydrated and in the freeze-dried state revealed differences in elemental distribution of particular elements at the cellular level due to the morphology alteration in particular tissue compartments induced either by water removal in the lyophilisation process or by unsatisfactory preparation of samples for cutting and mounting during the shock-freezing phase of sample preparation

  13. Community dynamics drive punctuated engraftment of the fecal microbiome following transplantation using freeze-dried, encapsulated fecal microbiota.

    Science.gov (United States)

    Staley, Christopher; Vaughn, Byron P; Graiziger, Carolyn T; Singroy, Stephanie; Hamilton, Matthew J; Yao, Dan; Chen, Chi; Khoruts, Alexander; Sadowsky, Michael J

    2017-05-04

    Fecal microbiota transplantation (FMT) is a highly effective treatment of recurrent and recalcitrant Clostridium difficile infection (rCDI). In a recent study oral-delivery of encapsulated, freeze-dried donor material, resulted in comparable rates of cure to colonoscopic approaches. Here we characterize shifts in the fecal bacterial community structure of patients treated for rCDI using encapsulated donor material. Prior to FMT, patient fecal samples showed declines in diversity and abundance of Firmicutes and Bacteroidetes, with concurrent increases in members of the Proteobacteria, specifically Enterobacteriaceae. Moreover, patients who experienced recurrence of CDI within the 2-month clinical follow-up had greater abundances of Enterobacteriaceae and did not show resolution of dysbioses. Despite resolution of rCDI following oral-administration of encapsulated fecal microbiota, community composition was slow to return to a normal donor-like assemblage. Post-FMT taxa within the Firmicutes showed rapid increases in relative abundance and did not vary significantly over time. Conversely, Bacteroidetes taxa only showed significant increases in abundance after one month post-FMT, corresponding to significant increases in the community attributable to the donors. Changes in the associations among dominant OTUs were observed at days, weeks, and months post-FMT, suggesting shifts in community dynamics may be related to the timing of increases in abundance of specific taxa. Administration of encapsulated, freeze-dried, fecal microbiota to rCDI patients resulted in restoration of bacterial diversity and resolution of dysbiosis. However, shifts in the fecal microbiome were incremental rather than immediate, and may be driven by changes in community dynamics reflecting changes in the host environment.

  14. Pore architecture and cell viability on freeze dried 3D recombinant human collagen-peptide (RHC)–chitosan scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jing; Zhou, Aimei; Deng, Aipeng [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Yang, Yang [Faculty of Engineering, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Gao, Lihu; Zhong, Zhaocai [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Yang, Shulin, E-mail: yshulin@njust.edu.cn [School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2015-04-01

    Pore architecture of 3D scaffolds used in tissue engineering plays a critical role in the maintenance of cell survival, proliferation and further promotion of tissue regeneration. We investigated the pore size and structure, porosity, swelling as well as cell viability of a series of recombinant human collagen-peptide–chitosan (RHCC) scaffolds fabricated by lyophilization. In this paper, freezing regime containing a final temperature of freezing (T{sub f}) and cooling rates was applied to obtain scaffolds with pore size ranging from 100 μm to 120 μm. Other protocols of RHC/chitosan suspension concentration and ratio modification were studied to produce more homogenous and appropriate structural scaffolds. The mean pore size decreased along with the decline of T{sub f} at a slow cooling rate of 0.7 °C/min; a more rapid cooling rate under 5 °C/min resulted to a smaller pore size and more homogenous microstructure. High concentration could reduce pore size and lead to thick well of scaffold, while improved the ratio of RHC, lamellar and fiber structure coexisted with cellular pores. Human umbilical vein endothelial cells (HUVECs) were seeded on these manufactured scaffolds, the cell viability represented a negative correlation to the pore size. This study provides an alternative method to fabricate 3D RHC–chitosan scaffolds with appropriate pores for potential tissue engineering. - Highlights: • Fabrication of recombinant human collagen-chitosan scaffolds by freezing drying • Influence of freeze drying protocols on lyophilized scaffolds • Pore size, microstructure, porosity, swelling and cell viability were compared. • The optimized porous scaffold is suitable for cell (HUVEC) seeding.

  15. Effect of whey protein isolate and β-cyclodextrin wall systems on stability of microencapsulated vanillin by spray-freeze drying method.

    Science.gov (United States)

    Hundre, Swetank Y; Karthik, P; Anandharamakrishnan, C

    2015-05-01

    Vanillin flavour is highly volatile in nature and due to that application in food incorporation is limited; hence microencapsulation of vanillin is an ideal technique to increase its stability and functionality. In this study, vanillin was microencapsulated for the first time by non-thermal spray-freeze-drying (SFD) technique and its stability was compared with other conventional techniques such as spray drying (SD) and freeze-drying (FD). Different wall materials like β-cyclodextrin (β-cyd), whey protein isolate (WPI) and combinations of these wall materials (β-cyd + WPI) were used to encapsulate vanillin. SFD microencapsulated vanillin with WPI showed spherical shape with numerous fine pores on the surface, which in turn exhibited good rehydration ability. On the other hand, SD powder depicted spherical shape without pores and FD encapsulated powder yielded larger particle sizes with flaky structure. FTIR analysis confirmed that there was no interaction between vanillin and wall materials. Moreover, spray-freeze-dried vanillin + WPI sample exhibited better thermal stability than spray dried and freeze-dried microencapsulated samples. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Rational design of an influenza subunit vaccine powder with sugar glass technology : preventing conformational changes of haemagglutinin during freezing and freeze-drying

    NARCIS (Netherlands)

    Amorij, J-P; Meulenaar, J; Hinrichs, W L J; Stegmann, T; Huckriede, A; Coenen, F; Frijlink, H W

    2007-01-01

    The development of a stable influenza subunit vaccine in the dry state was investigated. The influence of various carbohydrates, buffer types and freezing rates on the integrity of haemagglutinin after freeze-thawing or freeze-drying was investigated with a range of analytical and immunological

  17. On adaptive time stepping for large-scale parabolic problems: Computer simulation of heat and mass transfer in vacuum freeze-drying

    Czech Academy of Sciences Publication Activity Database

    Georgiev, K.; Kosturski, N.; Margenov, S.; Starý, Jiří

    2009-01-01

    Roč. 226, č. 2 (2009), s. 268-274 ISSN 0377-0427 Institutional research plan: CEZ:AV0Z30860518 Keywords : Vacuum freeze drying * Zeolites * Heat and mass transfer * Finite element method * MIC(0) preconditioning Subject RIV: BA - General Mathematics Impact factor: 1.292, year: 2009 http://apps.isiknowledge.com

  18. PREPARATION, CHARACTERIZATION, AND PHARMACEUTICAL APPLICATION OF LINEAR DEXTRINS .2. COMPLEXATION AND DISPERSION OF DRUGS WITH AMYLODEXTRIN BY FREEZE-DRYING AND KNEADING

    NARCIS (Netherlands)

    WIERIK, GHPT; EISSENS, AC; BESEMER, AC; LERK, CF

    The ability of amylodextrin (a linear dextrin) to act as a complexing agent or as a carrier for solid dispersion was evaluated. Blends of amylodextrin with diazepam or prednisolone were freeze-dried and kneaded at elevated temperatures, respectively. The products were analyzed by DSC, X-ray

  19. Freeze drying of nanosuspensions, 2: the role of the critical formulation temperature on stability of drug nanosuspensions and its practical implication on process design.

    Science.gov (United States)

    Beirowski, Jakob; Inghelbrecht, Sabine; Arien, Albertina; Gieseler, Henning

    2011-10-01

    The present study investigates whether controlling the product temperature below the critical formulation temperature (CFT) during primary drying in a freeze drying cycle is a prerequisite for the stabilization of drug nanoparticles. For that purpose, the CFT of four drug nanosuspensions stabilized with different types (amorphous and crystalline) and concentrations of steric stabilizers and either of the disaccharides, trehalose and sucrose, was determined by differential scanning calorimetry and freeze-dry microscopy. Freeze-drying experiments were performed such that product temperatures during primary drying remained either below or well above the CFT of individual mixtures. It was found that glass formation did not influence the stability of the nanoparticles, suggesting that an adequate type of steric stabilizer and lyoprotectant concentration is present. Freeze drying could also be performed above the eutectic temperature without compromising on the final product quality profile, such as nanoparticle size and structural preservation of the lyophilized cake. The high concentration of solid drug nanoparticles provided additional cake stability. The results of this study confirm for the first time that primary drying for drug nanosuspensions can be greatly shortened because induced viscous flow or even meltback is not a limitation for nanoparticle stability and cake elegancy. Copyright © 2011 Wiley-Liss, Inc.

  20. Optimization of a protective medium for enhancing the viability of freeze-dried Bacillus amyloliquefaciens B1408 based on response surface methodology.

    Science.gov (United States)

    Han, Lingjuan; Pu, Taixun; Wang, Xi; Liu, Beiling; Wang, Yonghong; Feng, Juntao; Zhang, Xing

    2018-02-16

    Response surface methodology (RSM) is a commonly used system to optimize cryoprotectants of biocontrol strains when they are subjected to preparations. Various kinds of cryoprotectants and centrifugal conditions were tested to improve the survival of biocontrol agents after freeze-drying. To determine the optimum levels of incorporation of three cryoprotectants (glucose, trehalose and xylitol) in the freeze-drying process of strain Bacillus amyloliquefaciens B1408, a range of experiments based on Box-Behnken Design (BBD) were conducted. The results indicated that the suitable centrifugation conditions were 5000 r/min,10 min and the optimum concentrations of cryoprotectants were glucose 1.00%, trehalose 4.74% and xylitol 1.45%. The proven survival rate of cells after freeze-drying was 91.24%. These results convincingly demonstrated that freeze-drying could be used to preparation of biocontrol strain B1408. This study provides a theoretical basis for commercial possibilities and formulation development. Copyright © 2018. Published by Elsevier Inc.

  1. Global Sensitivity Analysis as Good Modelling Practices tool for the identification of the most influential process parameters of the primary drying step during freeze-drying

    DEFF Research Database (Denmark)

    Van Bockstal, Pieter-Jan; Mortier, Séverine Thérèse F.C.; Corver, Jos

    2018-01-01

    Pharmaceutical batch freeze-drying is commonly used to improve the stability of biological therapeutics. The primary drying step is regulated by the dynamic settings of the adaptable process variables, shelf temperature Ts and chamber pressure Pc. Mechanistic modelling of the primary drying step...

  2. Influence of different sugar cryoprotectants on the stability and physico-chemical characteristics of freeze-dried 5-fluorouracil plurilamellar vesicles

    Directory of Open Access Journals (Sweden)

    Mohamed Mahmoud Nounou

    2005-07-01

    Full Text Available Lyophilization increases the shelf-life of liposomes by preserving it in a dry form as lyophilized cake to be reconstituted with water immediately prior to administration. Aiming at increasing stability and availability of 5-Fluorouracil liposomal products, 5-Fluorouacil Stable Plurilamellar Vesicles were prepared. Freeze dried liposomal dispersions were prepared with or without cryoprotectants. The cryoprotectants used were glucose, mannitol or trehalose in 1, 2 and 4 grams per gram phospholipids. The results showed that lyophilized cake of liposomes without cryoprotectants was compact and difficult to reconstitute, in comparison with fluffy cakes which reconstituted easily and quickly when using cryoprotectants. The percentage of 5-Fluorouracil retained in liposomes freeze-dried without cryoprotectants was 18.29% ± 0.96% and the percentage of 5-Fluorouracil retained in stable plurilamellar vesicles was 31.22% ± 0.62% using 4 grams trehalose as cryoprotectant per gram of lipid. Physico-chemical and release stability studies showed superior potentials of the lyophilized product after reconstitution in comparison to dispersion product. It may be concluded that all tested sugars have cryoprotectant effects that stabilized liposomes in the freeze dried state, where trehalose offered the most superior cryoprotectant effect for freeze dried 5-fluorouracil liposomes.

  3. Phosphatidylcholine: cholesterol phase diagrams.

    Science.gov (United States)

    Thewalt, J L; Bloom, M

    1992-10-01

    Two mono-cis-unsaturated phosphatidylcholine (PC) lipid molecules, having very different gel-liquid crystalline phase transition temperatures as a consequence of the relative positions of the double bond, exhibit PC:cholesterol phase diagrams that are very similar to each other and to that obtained previously for a fully saturated PC:cholesterol mixture (Vist, M. R., and J. H. Davis. 1990. Biochemistry 29:451-464). This leads to the conjecture that PC:cholesterol membrane phase diagrams have a universal form which is relatively independent of the precise chemical structure of the PC molecule. One feature of this phase diagram is the observation over a wide temperature range of a fluid but highly conformationally ordered phase at bilayer concentrations of more than approximately 25 mol% cholesterol. This ;liquid ordered' phase is postulated to be the relevant physical state for many biological membranes, such as the plasma membrane of eukaryotic cells, that contain substantial amounts of cholesterol or equivalent sterols.

  4. [Application of small freeze-drying allogeneic bone plots mixed with autologous bone graft in spinal fusion].

    Science.gov (United States)

    Tian, Changqing; Li, Zhenyu; Zhou, Wenyu; Zeng, Tenghui; Sun, Shiquan; Li, Baoxing

    2009-05-01

    To investigate the osteoblasts effect, complications and influencing factors in the application of small freeze-drying allogeneic bone plots mixed autologous bone fragments in spinal surgery, and to compare with autogenous bone graft. From January 2003 to January 2007, 515 cases of spinal injuries were treated. A total of 324 cases were treated with small freeze-drying allogeneic bone plots mixed with autologous bone grafts (group A), including 211 males and 113 females with an average age of 36 years (18-83 years). There were 182 cases of thoracolumbar vertebra fracture, 68 cases of lumbar spondylolisthesis, 47 cases of lumbar vertebral canal stenosis, 17 cases of cervical disc herniation, 5 cases of cervical spine fracture-dislocation and 5 cases of thoracolumbar vertebra tumor. The weight of bone graft was 10-60 g (mean 30 g). A total of 191 cases were treated with autogenous bone grafting (group B), including 135 males and 56 females with an average age of 32 years (23-78 years). There were 109 cases of thoracolumbar vertebra fracture, 23 cases of lumbar spondylolisthesis, 17 cases of lumbar vertebral canal stenosis, 19 cases of cervical disc herniation, and 23 cases of cervical spine fracture-dislocation. The weight of bone graft was 10-50 g (mean 25 g). In group A, effusion of wound increased in 4 cases and the result of bacterial culture was negative; effusion was absorbed after 2 weeks of local irrigation, drainage and cortin management. In group B, no obvious effusion was observed. The follow-up time was 10-36 months (mean 17.4 months) in group A and 8-36 months (mean 16.8 months) in group B. The bone healing was achieved in 308 cases within 4-10 months (mean 8.1 months) and in 184 cases within 4-10 months (mean 5.8 months), and the bone fusion rates were 95.06% and 96.34% in groups A and B, respectively. There was no significant difference in bone fusion rate between groups (P > 0.05). According to Mankin and Komender evaluation standard, the response

  5. Screening Quality Evaluation Factors of Freeze-Dried Peach (Prunus Persica L. Batsch Powders from Different Ripening Time Cultivars

    Directory of Open Access Journals (Sweden)

    Chun-ju Liu

    2017-01-01

    Full Text Available The quality evaluation of processed products is complex. To simplify the quality evaluation process and improve the efficiency, fourteen evaluation factors of freeze-dried powders of seventeen cultivars of peach at different ripening times were analyzed. The most important evaluation indicators and criteria were obtained by analysis of variance (ANOVA, correlation analysis (CA, principal component analysis (PCA, system cluster analysis (SCA, and analytic hierarchy process (AHP. Results showed that the peach powders had the significant differences in quality (P<0.05, and some processing factors were related with some physicochemical and nutritional factors. Five principle components were extracted by PCA and the cumulative contribution achieved was 84.46%. Through the score plot of the first two principal components, a clear differentiation among ripening times was found and three distinct groups were separated according to ripening time. Five characteristic factors were obtained as titratable acid, browning index, hemicellulose, hygroscopicity, and vitamin C by SCA. Their weights of 0.1249, 0.3007, 0.0514, 0.4916, and 0.0315 were obtained by AHP, respectively. The peach cultivars were divided into four evaluation grades by the comprehensive quality score.

  6. Changes in physical and gelling properties of freeze-dried egg white as a result of temperature and relative humidity.

    Science.gov (United States)

    Katekhong, Wattinee; Charoenrein, Sanguansri

    2016-10-01

    The quality of dried egg white with respect to functional properties can be affected by storage conditions. The effect of temperature and relative humidity (RH) on changes in colour and gelling properties in freeze-dried egg white (FDEW) during storage was investigated. The glass transition temperature (Tg ) of FDEW decreased with increasing % RH. The colour of FDEW stored at 60 °C was darker yellow than those at 40 and 25 °C, particularly at high % RH. RH had no effect on hardness and water-holding capacity (WHC) of gels made from FDEW stored at 25 °C for 1 week. However, hardness and WHC of gels from FDEW stored at higher temperatures; 40 °C, 48% RH and 60 °C, 11% RH dramatically increased. These results related to the differential scanning calorimeter thermograms which showed a broadening peak with lower enthalpy of protein denaturation. Moreover, the protein's SDS-PAGE pattern in the samples stored at high temperatures or RH levels showed protein aggregation. Storage of FDEW at high temperature and RH levels induced protein conformation changes. These have contributed to protein aggregation which affected the gelling properties of FDEW. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  7. Socket preservation using freeze-dried bone allograft with and without plasma rich in growth factors in dogs

    Directory of Open Access Journals (Sweden)

    Mohammad Hasan Samandari

    2016-01-01

    Full Text Available Background: Plasma rich in growth factors (PRGF and freeze-dried bone allograft (FDBA are shown to promote bone healing. This study was aimed to histologically and histomorphometrically investigate the effect of combined use of PRGF and FDBA on bone formation, and compare it to FDBA alone and control group. Materials and Methods: The distal roots of the lower premolars were extracted bilaterally in four female dogs. Sockets were randomly divided into FDBA + PRGF, FDBA, and control groups. Two dogs were sacrificed after 2 weeks and two dogs were sacrificed after 4 weeks. Sockets were assessed histologically and histomorphometrically. Data were analyzed by Kruskal-Wallis test followed by Mann-Whitney U-tests utilizing the SPSS software version 20. P < 0.05 was considered statistically significant. Results: While the difference in density of fibrous tissue in three groups was not statistically significant (P = 0.343, the bone density in grafted groups was significantly higher than the control group (P = 0.021. The least decrease in all socket dimensions was observed in the FDBA group. However, these differences were only significant in coronal portion at week 4. Regarding socket dimensions and bone density, the difference between FDBA and FDBA+PRGF groups was not significant in middle and apical portions. Conclusion: The superiority of PRGF+FDBA overFDBA in socket preservation cannot be concluded from this experiment.

  8. Breads Fortified with Freeze-Dried Vegetables: Quality and Nutritional Attributes. Part II: Breads Not Containing Oil as an Ingredient

    Directory of Open Access Journals (Sweden)

    Viren Ranawana

    2016-09-01

    Full Text Available The present article describes the second part of a study investigating the effect of adding vegetables on the nutritional, physico-chemical, and oxidative properties of wheat bread, and specifically focuses on bread that does not contain oil as an added ingredient. Wheat flour breads fortified with freeze-dried carrot, tomato, beetroot or broccoli were developed and assessed for their nutritional composition, antioxidant potential, oxidative stability, and storage properties. Using a simulated in vitro model, the study also examined the impact of vegetable addition on the oxidative stability of macronutrients during gastro-intestinal digestion. Adding vegetables improved the nutritional and functional attributes of the oil-free breads. However, they demonstrated a lower antioxidant potential compared to their oil-containing counterparts. Similarly, the textural and storage properties of the oil-free vegetable breads were poorer compared to the oil-containing breads. As expected, in the absence of oil the oil-free breads were associated with lower lipid oxidation both in their fresh form and during gastro-intestinal digestion. Adding vegetables reduced protein oxidation in the fresh oil-free breads but had no effect during gastro-intestinal digestion. The impact of vegetables on macronutrient oxidation in the oil-free breads during digestion appears to be vegetable-specific with broccoli exacerbating it and the others having no effect. Of the evaluated vegetables, beetroot showed the most promising nutritional and physico-chemical benefits when incorporated into bread that does not contain added oil.

  9. Breads Fortified with Freeze-Dried Vegetables: Quality and Nutritional Attributes. Part 1: Breads Containing Oil as an Ingredient

    Directory of Open Access Journals (Sweden)

    Viren Ranawana

    2016-03-01

    Full Text Available There is increasing emphasis on reformulating processed foods to make them healthier. This study for the first time comprehensively investigated the effects of fortifying bread (containing oil as an ingredient with freeze-dried vegetables on its nutritional and physico-chemical attributes. Breads fortified with carrot, tomato, beetroot or broccoli were assessed for nutrition, antioxidant potential, storage life, shelf stability, textural changes and macronutrient oxidation. Furthermore, using an in vitro model the study for the first time examined the impact of vegetable addition on the oxidative stability of macronutrients during human gastro-intestinal digestion. As expected, adding vegetables improved the nutritional and antioxidant properties of bread. Beetroot and broccoli significantly improved bread storage life. None of the vegetables significantly affected bread textural changes during storage compared to the control. Lipid oxidation in fresh bread was significantly reduced by all four types of vegetables whilst protein oxidation was lowered by beetroot, carrot and broccoli. The vegetables demonstrated varying effects on macronutrient oxidation during gastro-intestinal digestion. Beetroot consistently showed positive effects suggesting its addition to bread could be particularly beneficial.

  10. Effects of Freeze-dried Mulberry on Antioxidant Activities and Fermented Characteristics of Yogurt during Refrigerated Storage

    Science.gov (United States)

    2015-01-01

    This study investigated the effect of added freeze-dried mulberry fruit juice (FDMJ) (1, 3 and 5%) on the antioxidant activity and fermented characteristic of yogurt during refrigerated storage. A decrease in pH of yogurt and increase in acidity was observed during fermentation. The yogurts with FDMJ exhibited faster rate of pH reduction than control. Initial lactic acid bacteria count of yogurt was 6.49-6.94 Log CFU/g and increased above 9 Log CFU/g in control and 1% in FDMJ yogurt for 24 h. The total polyphenol and anthocyanin content of FDMJ yogurt was higher than that of control due to the presence of phytochemical contents in mulberry. Moreover, antioxidant activity such as DPPH and reducing power was highest 5% FDMJ yogurt. During cold storage, pH decreased or remained constant in all yogurts with values ranging from 4.08 to 4.78 units. In sensory evaluation, the score of 1% FDMJ yogurt was ranked higher when compared with other yogurts. It is proposed that mulberry fruit juice powder can be used to improve sensory evaluation and enhance functionality of yogurt. PMID:26877641

  11. Improved viability of Lactobacillus acidophilus NRRL-B 4495 during freeze-drying in whey protein-pullulan microcapsules.

    Science.gov (United States)

    Çabuk, Burcu; Harsa, Şebnem Tellioglu

    2015-01-01

    In this research, pullulan was incorporated in protein-based encapsulation matrix in order to assess its cryoprotective effect on the viability of freeze-dried (FD) probiotic Lactobacillus acidophilus NRRL-B 4495. This study demonstrated that pullulan in encapsulation matrix resulted in a 90.4% survival rate as compared to 88.1% for whey protein (WPI) encapsulated cells. The protective effects of pullulan on the survival of FD-encapsulated cells in gastrointestinal conditions were compared. FD WPI-pullulan capsules retained higher survived cell numbers (7.10 log CFU/g) than those of FD WPI capsules (6.03 log CFU/g) after simulated gastric juice exposure. Additionally, use of pullulan resulted in an increased viability after bile exposure. FD-free bacteria exhibited 2.18 log CFU/g reduction, while FD WPI and FD WPI-pullulan encapsulated bacteria showed 0.95 and 0.49 log CFU/g reduction after 24 h exposure to bile solution, respectively. Morphology of the FD microcapsules was visualized by scanning electron microscopy.

  12. Influence of product thickness, chamber pressure and heating conditions on production rate of freeze-dried yoghurt

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, N.K. [G.B. Pant Univ., of Agriculture and Technology (India). Dept. of Mechanical Engineering; Arora, C.P. [Indian Inst. of Tech., New Delhi (India)

    1995-06-01

    The effects of product thickness, chamber pressure and heating conditions on product temperature profiles and production rate of freeze-dried yoghurt were investigated experimentally. Three sample thicknesses - 3.8 mm, 6.2 mm and 9.4 mm - were tested at chamber pressures of 0.01 and 0.5 mmHg. The production rate increased by decreasing product thickness in contact heating through the bottom of the frozen layer, whereas no significant change was observed in radiant heating. A reduction in chamber pressure from 0.50 to 0.01 mmHg increased the drying time in radiant heating. Maximum production rate was obtained when the thickness of dried product was 6.2 mm, when heat was transferred simultaneously through the frozen and dried layers, and the chamber pressure was at 0.01 mmHg. Use of the product tray developed in this study prevents the growth of dry layers at the contact surfaces. (Author)

  13. Prospective Clinical and Radiographic Study of Alveolar Ridge Preservation Combining Freeze-Dried Bone Allograft With Two Xenogeneic Collagen Matrices.

    Science.gov (United States)

    Parashis, Andreas O; Hawley, Charles E; Stark, Paul C; Ganguly, Rumpa; Hanley, James B; Steffensen, Bjorn

    2016-04-01

    Tooth extractions are followed by significant dimensional changes in the alveolar crest that may preclude implant placement. This randomized, controlled, prospective compares the preservation of soft and hard tissue dimensional changes after alveolar ridge preservation (ARP) using two membranes consisting of collagen matrix (CM) or extracellular matrix (ECM) as barriers over freeze-dried bone allograft (FDBA). Standardized clinical and radiographic measurements of soft and hard tissues were recorded by means of a stent before and 4 months after ARP. The surgery entailed sulcular incisions with minimal flap elevation and repositioning without advancement. Of 11 patients in the CM group and 12 in the ECM group who completed the study, gingival thickness (GT) increased from 0.1 to 0.2 mm for both groups along with a 0.5-mm decrease in the width of keratinized tissue after healing. Reductions in ridge width were most pronounced on the coronal aspect, 1.8 mm for CM and 2.0 mm for ECM, whereas vertical reduction was most pronounced on the buccal aspect, 0.7 to 1.0 mm. Differences between groups were not statistically significant. However, significant correlation for changes in GT (P = 0.001) and crestal bone width (P = 0.002) with preoperative buccal plate thickness (BPT) was observed. Both xenogeneic collagen matrices combined with FDBA were effective in maintaining soft tissues and minimizing ridge resorption in all dimensions after ARP. BPT was an important determinant for amount of change in crestal GT and ridge width.

  14. Bulk specimen X-ray microanalysis of freeze-fractured, freeze-dried tissues in gerontological research

    International Nuclear Information System (INIS)

    Nagy, I.

    1988-01-01

    The rationale for choosing the freeze-fracture freeze-drying (FFFD) method of biological bulk specimen preparation as well as the theoretical and practical problems of this method are treated. FFFD specimens are suitable for quantitative X-ray microanalysis of biologically relevant elements. Although the spatial resolution of this analytical technique is low, the application of properly selected bulk standard crystals as well as the measurement of the intracellular water and dry mass content by means of another method developed in the same laboratory, allow us to obtain useful information about the age-dependent changes of ionic composition in the main intracellular compartments. The paper summarizes the problems with regard to specimen preparation, beam penetration and the quantitative analysis of FFFD specimens. The method has been applied so far mainly for the analysis of intranuclear and intracytoplasmic concentrations of Na, C1 and K in various types of cells and has resulted in a significant contribution to our understanding of the cellular mechanisms of aging. 84 references

  15. {sup 68}Ga Labeling of DOTMP using Freeze-dried Kit for the Imaging of Bone Metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Dho, So Hee; Choi, Sangmu; Kim, Sooyong; Cho, Eunha; Lee, Soyoung; Jung, Sunghee; Lim, Jaecheong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    Bone is a favorable site of metastasis and is invaded common primary tumors such as prostate, breast, and lung. Due to the progressive pain and mortality of the bone metastasis, effort has been focused on the detection of bone metastasis in the field of nuclear medicine (Mitterhauser, Toegel et al. 2007, Mirzaei, Jalilian et al. 2015). In designing suitable imaging agents for bone metastasis, multidentate polyaminophosphonate are regarded as the most promising candidates as carrier ligands owing to their high bone affinity, selective localization in skeletal lesions and ability to form metal chelates with high in-vivo stability (Chakraborty, Das et al. 2008). 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene. Freeze-dried DOTMP kit vial was consist of 400 μ of DOTMP, 19.27 mg of ammonium acetate and 17.62 mg of ascorbic acid. All the preparative steps were carried out under aseptic conditions, and the prepared kit vials were shown in Fig. 3(A). The easy and efficient labeling of this kit with 68Ga make them suitable for preparing 68Ga-DOTMP for imaging of bone metastasis.

  16. Evaluation of Different Holder Devices for Freeze-Drying in Dual-Chamber Cartridges With a Focus on Energy Transfer.

    Science.gov (United States)

    Korpus, Christoph; Friess, Wolfgang

    2017-04-01

    For freeze-drying in dual-chamber cartridges, a holder device to enable handling and safe positioning in the freeze-dryer is necessary. The aim of this study was to analyze 4 different types of holder devices and to define the best system based on energy transfer. The main criteria were drying homogeneity, ability to minimize the influence of atypical radiation on product temperatures, and heat transfer effectiveness. The shell holder reduced the influence of atypical radiation by almost 60% compared to a block system and yielded the most homogenous sublimation rates. Besides the most efficient heat transfer with values of 1.58E-4 ± 2.06E-6 cal/(s*cm 2 *K) at 60 mTorr to 3.63E-4 ± 1.85E-5 cal/(s*cm 2 *K) at 200 mTorr for K tot , reaction times to shelf temperature changes were up to 4 times shorter compared to the other holder systems and even faster than for vials. The flexible holder provided a comparable shielding against atypical radiation as the shell but introduced a third barrier against energy transfer. Block and guardrail holder were the least efficient system tested. Hence, the shell holder provided the best radiation shielding, enhanced the transferability of the results to a larger scale, and improved the homogeneity between the dual-chamber cartridges. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  17. Improved storage stability and immunogenicity of hepatitis B vaccine after spray-freeze drying in presence of sugars.

    Science.gov (United States)

    Tonnis, W F; Amorij, J-P; Vreeman, M A; Frijlink, H W; Kersten, G F; Hinrichs, W L J

    2014-05-13

    The current hepatitis B vaccines need to be stored and transported under refrigerated conditions (2-8°C). This dependence on a cold-chain is highly challenging in areas where hepatitis B virus infections are endemic. To decrease the cold-chain dependency, powder formulations of the hepatitis B surface antigen (HBsAg) without aluminum were prepared by spray-freeze drying in the presence of either inulin or a combination of dextran and trehalose. The stability of HBsAg in the amorphous powder formulations was strongly improved during storage both at room temperature and at an elevated temperature (60°C), compared to a liquid plain and an aluminum hydroxide adjuvanted HBsAg formulation. Immunogenicity studies in mice showed that reconstituted powder formulations induced higher IgG immune responses after intramuscular administration than those induced after administration of unprocessed plain antigen. Although the immune response was not as high as after administration of aluminum adjuvanted HBsAg, the immune response to the reconstituted vaccines shifted towards a more balanced Th1/Th2 response compared to the aluminum containing HBsAg formulation. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Mechanistic modelling of infrared mediated energy transfer during the primary drying step of a continuous freeze-drying process.

    Science.gov (United States)

    Van Bockstal, Pieter-Jan; Mortier, Séverine Thérèse F C; De Meyer, Laurens; Corver, Jos; Vervaet, Chris; Nopens, Ingmar; De Beer, Thomas

    2017-05-01

    Conventional pharmaceutical freeze-drying is an inefficient and expensive batch-wise process, associated with several disadvantages leading to an uncontrolled end product variability. The proposed continuous alternative, based on spinning the vials during freezing and on optimal energy supply during drying, strongly increases process efficiency and improves product quality (uniformity). The heat transfer during continuous drying of the spin frozen vials is provided via non-contact infrared (IR) radiation. The energy transfer to the spin frozen vials should be optimised to maximise the drying efficiency while avoiding cake collapse. Therefore, a mechanistic model was developed which allows computing the optimal, dynamic IR heater temperature in function of the primary drying progress and which, hence, also allows predicting the primary drying endpoint based on the applied dynamic IR heater temperature. The model was validated by drying spin frozen vials containing the model formulation (3.9mL in 10R vials) according to the computed IR heater temperature profile. In total, 6 validation experiments were conducted. The primary drying endpoint was experimentally determined via in-line near-infrared (NIR) spectroscopy and compared with the endpoint predicted by the model (50min). The mean ratio of the experimental drying time to the predicted value was 0.91, indicating a good agreement between the model predictions and the experimental data. The end product had an elegant product appearance (visual inspection) and an acceptable residual moisture content (Karl Fischer). Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Immunomodulatory effects of supercritical fluid CO2 extracts from freeze-dried powder of Tenebrio molitor larvae (yellow mealworm

    Directory of Open Access Journals (Sweden)

    QingFeng TANG

    2016-01-01

    Full Text Available Abstract In order to take full advantage of Tenebrio molitor larvae (yellow mealworm resources, the supercritical CO2 fluid freeze-dried powder of T. molitor larvae (fdTML extraction on the immune systems of mice was carried out. The results about the effects of supercritical CO2 fluid fdTML extraction on carbon expurgation and phagocytosis of peritoneal macrophages experiments of mice indicated that the fdTML extraction enhanced observably carbon expurgatory index, phagocytic rate and phagocytic index. The fdTML extraction could stimulate response of delayed hypersensitivity. The proliferation of ConA-induced mitogenic reponse for spleen lymphocyte was also increased. The amount of hemolytic antibody in mice serum increased compared with those of the control group mice. The half of hemolysis values in serum of treated mice increased compared to the control group. Furthermore, serum NO content in all treatment groups was higher than that of the control group whereas acid phosphatase and alkaline phosphatase activity was only significantly higher relative to the control group. Our findings suggest that supercritical CO2 fluid the fdTML extraction has potential as a health food supplement.

  20. Chemical compositions and antioxidant/anti-inflammatory activities of steam distillate from freeze-dried onion ( Allium cepa L.) sprout.

    Science.gov (United States)

    Takahashi, Mizuho; Shibamoto, Takayuki

    2008-11-26

    Freeze-dried onion sprout was steam-distilled, and the distillate was extracted with dichloromethane (volatile sample). Water sample I was obtained from the residual aqueous solution in the extractor. The filtrate and the methanol extract of filtrand from the residual aqueous solution in the steam distillation flask were named water sample II and methanol sample, respectively. Among the total of 71 components identified in the volatile sample, 24 were sulfur-containing compounds, which comprised 36.87% of the total volatile chemicals identified. The volatile sample inhibited hexanal oxidation for 40 days by >99% at levels >100 microg/mL. The volatile sample and water sample II exhibited moderate antioxidant activity in a malonaldehyde/gas chromatography assay and thiobarbituric acid assay, whereas water sample I did not show appreciable activity. The volatile sample, water sample I, and water sample II exhibited anti-inflammatory activity with a dose-related response in the lipoxygenase inhibitor screening assay. However, the methanol sample did not show appreciable activity in either antioxidant or anti-inflammatory tests. The results suggest that onion sprouts can be an excellent food source.

  1. The Palatability of Lopinavir and Ritonavir Delivered by an Innovative Freeze-Dried Fast-Dissolving Tablet Formulation

    Directory of Open Access Journals (Sweden)

    David W. Pittman

    2018-01-01

    Full Text Available Negative hedonic sensory qualities of HIV antiretroviral drugs often reduce patient adherence particularly in pediatric populations requiring oral consumption. This study examines the palatability of an innovative delivery mechanism utilizing a freeze-drying-in-blister approach to create fast-dissolving tablets (FDTs containing a fixed-dose combination of lopinavir and ritonavir (LPV/r. Consumption patterns of solutions during brief-access and long-term testing and baby foodstuff consumption were analyzed to evaluate the orosensory detection and avoidance of placebo FDTs containing no LPV/r (FDT− and FDTs containing LPV/r (FDT+. Rats showed no change in consumption patterns for the placebo FDT− compared with control solutions. Rats can detect but do not avoid FDT+ at body-weight-adjusted dosages in both brief-access (30-s and long-term (23 h consumption tests. There is an aversive response to concentrated doses of FDT+ during brief-access tests that cannot be masked by 25% sucrose. However, the strongest FDT+ concentration was not rejected when mixed with 50 g of applesauce, banana sauce, or rice cereal baby foodstuffs. The averseness of the FDT+ was associated with the presence of LPV/r and not the FDT− formulation itself. The novel FDT formulation appears to be a palatable delivery mechanism for oral antiretroviral pharmaceuticals especially when mixed with baby foodstuffs.

  2. High homogeneity powder of Ti-Ba-Ca-Cu-O (2223) prepared by Freeze-Drying method

    International Nuclear Information System (INIS)

    Al-Shakarchi, Emad Kh.; Toma, Ziad A.

    1999-01-01

    Full text.Homogeneous high temerature superconductor ceramic powder of TI-Ba-Ca-Cu-O with transition temperature [Tc=123K] have been successfully prepared from the mixture of nitrate salts [TlNO 3 , Ba(NO 3 ) 2 , Ca(NO 3 ) 2 .4H 2 O and Cu(NO 3 ) 2 .3H 2 O] by using freeze-drying method. Freeze-dryer that was used in this work designed locally in our laboratory. This technique consider a better to get a fine powder of ceramic materials by depending on the procedure of frozen droplets with present of liquid nitrogen. SEM pictures showed the size of grains of about [0.8 μm]. We conclude that the high sintering temperature, for the prepared powders in this technique, for long time [120 hrs] will increase the inter diffusion between the grains ahich caused the decreasing in the density of the sample which may be given a better results than the obtained in a previous works

  3. Fermentation conditions influence the fatty acid composition of the membranes of Lactobacillus reuteri I5007 and its survival following freeze-drying.

    Science.gov (United States)

    Liu, X T; Hou, C L; Zhang, J; Zeng, X F; Qiao, S Y

    2014-10-01

    Lactobacillus reuteri I5007 has well-documented adhesion properties and health benefits. Future industrial use of Lact. reuteri I5007 will require the development of effective fermentation procedures and high bacterial survival following drying. Therefore, this study was conducted to determine the impact of altering fermentation pH and temperature on the fatty acid composition of the bacterial membranes and subsequent survival of Lact. reuteri I5007 following freeze-drying. Initially, a response surface methodology was used to determine the optimal fermentation pH (5·7) and temperature (37°C), with regard to producing the maximum number of Lact. reuteti I5007 cells. However, when subjected to the optimal fermentation pH and temperature (control treatment), the subsequent survival of Lact. reuteri I5007 following freeze-drying was only 12·95%. Growth at a higher temperature (47°C) or at a neutral pH (pH 6·7) significantly increased the survival of Lact. reuteri I5007 following freeze-drying compared with the control. In contrast, an acidic pH (pH 4·7), or cold (27°C) and extremely cold (4°C) temperatures during fermentation significantly reduced Lact. reuteri I5007 survival following freeze-drying. The fatty acid composition of the membranes of Lact. reuteri I5007 was altered by the different fermentation conditions tested. An increase in the ratio of unsaturated fatty acids (UFA) to saturated fatty acids (SFA) in the bacterial membrane was associated with higher survival of Lact. reuteri I5007. In conclusion, it appears that the use of a higher temperature (47°C) or neutral pH (6·7) during fermentation resulted in increased survival of Lact. reuteri I5007 following freeze-drying. Significance and impact of the study: In this study, we found that a higher fermentation temperature or a neutral pH, rather than cold or acidic conditions, leads to increased survival of Lact. reuteri I5007 during subsequent freeze-drying. This finding has important implications

  4. Encapsulation of antioxidant phenolic compounds extracted from spent coffee grounds by freeze-drying and spray-drying using different coating materials

    DEFF Research Database (Denmark)

    Ballesteros, Lina F.; Ramirez, Monica J.; Orrego, Carlos E.

    2017-01-01

    Freeze-drying and spray-drying techniques were evaluated for encapsulation of phenolic compounds (PC) extracted from spent coffee grounds. Additionally, the use of maltodextrin, 29 gum arabic and a mixture of these components (ratio 1:1) as wall material to retain the PC and preserve their antiox......% and 73%, respectively, and 73-86% of the antioxidant activity present in the original extract was preserved.......Freeze-drying and spray-drying techniques were evaluated for encapsulation of phenolic compounds (PC) extracted from spent coffee grounds. Additionally, the use of maltodextrin, 29 gum arabic and a mixture of these components (ratio 1:1) as wall material to retain the PC and preserve...... their antioxidant activity was also assessed. The contents of PC and flavonoids (FLA), as well as the antioxidant activity of the encapsulated samples were determined in order to verify the efficiency of each studied condition. Additional analyses for characterization of the samples were also performed. Both...

  5. Evaluation of shrinkage temperature of bovine pericardium tissue for bioprosthetic heart valve application by differential scanning calorimetry and freeze-drying microscopy

    Directory of Open Access Journals (Sweden)

    Virgilio Tattini Jr

    2007-03-01

    Full Text Available Bovine pericardium bioprosthesis has become a commonly accepted device for heart valve replacement. Present practice relies on the measurement of shrinkage temperature, observed as a dramatic shortening of tissue length. Several reports in the last decade have utilized differential scanning calorimetry (DSC as an alternative method to determine the shrinkage temperature, which is accompanied by the absorption of heat, giving rise to an endothermic peak over the shrinkage temperature range of biological tissues. Usually, freeze-drying microscope is used to determine collapse temperature during the lyophilization of solutions. On this experiment we used this technique to study the shrinkage event. The aim of this work was to compare the results of shrinkage temperature obtained by DSC with the results obtained by freeze-drying microscopy. The results showed that both techniques provided excellent sensitivity and reproducibility, and gave information on the thermal shrinkage transition via the thermodynamical parameters inherent of each method.

  6. Drug release profiles and microstructural characterization of cast and freeze dried vitamin B12 buccal films by positron annihilation lifetime spectroscopy.

    Science.gov (United States)

    Szabó, Barnabás; Kállai, Nikolett; Tóth, Gergő; Hetényi, Gergely; Zelkó, Romána

    2014-02-01

    Solvent cast and freeze dried films, containing the water-soluble vitamin B12 as model drug were prepared from two polymers, sodium alginate (SA), and Carbopol 71G (CP). The proportion of the CP was changed in the films. The microstructural characterization of various samples was carried out by positron annihilation lifetime spectroscopy (PALS). The drug release kinetics of untreated and stored samples was evaluated by the conventionally applied semi-empirical power law. Correlation was found between the changes of the characteristic parameters of the drug release and the ortho-positronium (o-Ps) lifetime values of polymer samples. The results indicated that the increase of CP concentration, the freeze-drying process and the storage at 75% R.H. decreased the rate of drug release. The PALS method enabled the distinction between the micro- and macrostructural factors influencing the drug release profile of polymer films. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Effect of Microencapsulation by Spray-Drying and Freeze-Drying Technique on the Antioxidant Properties of Blueberry (Vaccinium myrtillus Juice Polyphenolic Compounds

    Directory of Open Access Journals (Sweden)

    Wilkowska Agnieszka

    2016-03-01

    Full Text Available Blueberry juice with high polyphenol concentration was spray- or freeze-dried using different coating materials: HP-β-cyclodextrin and β-cyclodextrin. The quality of the obtained powders was characterised by their anthocyanin content, total polyphenols and antioxidant capacity. SEM was used for monitoring structures and size (2–20 μm of the microparticles. The losses of total phenolic compounds during spray-drying reached 76–78% on average, while these of anthocyanins about 57%. Freeze-dried powders showed better retention values of anthocyanins, which was about 1.5-fold higher than for the spray-dried counterparts. All blueberry preparations studied were characterised by very high radical scavenging activity.

  8. Enhancement of viability of a probiotic Lactobacillus strain for poultry during freeze-drying and storage using the response surface methodology.

    Science.gov (United States)

    Khoramnia, Anahita; Abdullah, Norhani; Liew, Siew Ling; Sieo, Chin Chin; Ramasamy, Kalavathy; Ho, Yin Wan

    2011-02-01

    A rotatable central composite design (CCD) was used to study the effect of cryoprotectants (skim milk, sucrose and lactose) on the survival rate of a probiotic Lactobacillus strain, L. reuteri C10, for poultry, during freeze-drying and storage. Using response surface methodology, a quadratic polynomial equation was obtained for response value by multiple regression analyses: Y = 8.59546-0.01038 X(1)-0.09382 X(2)-0.07771 X(3)-0.054861 X(1)(2)-0.04603 X(3)(2)-0.10938 X(1)X(2). Based on the model predicted, sucrose exerted the strongest effect on the survival rate. At various combinations of cryoprotectants, the viability loss of the cells after freeze-drying was reduced from 1.65 log colony forming units (CFU)/mL to 0.26-0.66 log CFU/mL. The estimated optimum combination for enhancing the survival rate of L. reuteri C10 was 19.5% skim milk, 1% sucrose and 9% lactose. Verification experiments confirmed the validity of the predicted model. The storage life of freeze-dried L. reuteri C10 was markedly improved when cryoprotectants were used. At optimum combination of the cryoprotectants, the survival rates of freeze-dried L. reuteri C10 stored at 4°C and 30°C for 6 months were 96.4% and 73.8%, respectively. Total viability loss of cells which were not protected by cryoprotectants occurred after 12 and 8 weeks of storage at 4°C and 30°C, respectively. © 2010 The Authors. Journal compilation © 2010 Japanese Society of Animal Science.

  9. Freeze-dried Lactobacillus plantarum 299v increases iron absorption in young females-Double isotope sequential single-blind studies in menstruating women.

    Directory of Open Access Journals (Sweden)

    Michael Hoppe

    Full Text Available The probiotic strain Lactobacillus plantarum 299v has earlier been shown to increase iron absorption when added to foods. However, it is not known if the same probiotic strain in a freeze-dried format included in a capsule increases the iron absorption.The aim of this study was to test the hypotheses that non-heme iron absorption from a light meal is promoted by a simultaneous intake of freeze-dried Lactobacillus plantarum 299v (Lp299v, DSM 9843.With a single blinded placebo controlled sequential design, iron absorption from a light breakfast meal administered with or without capsules containing 1010 cfu freeze-dried Lp299v was studied in healthy female volunteers of fertile age. The methodology used was a double isotope technique (59Fe and 55Fe. Two studies were performed using the same protocol.In study 1, the absorption of iron from a meal without Lp299v was found to be 17.4 ± 13.4%, and from an identical meal with Lp299v was found to be 22.4 ± 17.3% (mean ± SD. This difference was statistically significant (p = 0.040, n = 14. In study 2, the absorption of iron from a meal without Lp299v was found to be 20.9 ± 13.1%, and from an identical meal with Lp299v found to be 24.5 ± 12.0% (mean ± SD, n = 28, which again was statistically significant (p = 0.003.Freeze-dried Lp299v enhances the absorption of iron when administered together with a meal with a high iron bioavailability.ClinicalTrials.gov Identifier: NCT02131870.

  10. Improvement of a dry formulation of Pseudomonas fluorescens EPS62e for fire blight disease biocontrol by combination of culture osmoadaptation with a freeze-drying lyoprotectant.

    Science.gov (United States)

    Cabrefiga, J; Francés, J; Montesinos, E; Bonaterra, A

    2014-10-01

    To study the effect of lyoprotectants and osmoadaptation on viability of Pseudomonas fluorescens EPS62e during freeze-drying and storage and to evaluate the formulation in terms of efficacy in biocontrol and fitness on pear flowers. A wettable powder formulation of a biocontrol agent of fire blight was optimized by means of lyoprotectants and culture osmoadaptation. Freeze-drying was used to obtain dehydrated cells, and the best viability (70% of survival) was obtained using lactose as lyoprotectant. Survival during lyophilization was additionally improved using physiological adaptation of cells during cultivation under salt-amended medium (osmoadaptation). The procedure increased the survival of cells after freeze-drying attaining viability values close to a 100% in the lactose-formulated product (3 × 10(11) CFU g(-1) ), and through the storage period of 1 year at 4°C. The dry formulation showed also an improved biocontrol efficacy and survival of EPS62e on pear flowers under low relative humidity conditions. Cell viability after freeze-drying was improved using lactose as lyoprotectant combined with a procedure of osmoadaptation during cultivation. The powder-formulated product remained active for 12 months and retained biocontrol levels similar to that of fresh cells. The formulation showed an improved survival of EPS62e on flowers and an increase of the efficacy of biocontrol of fire blight at low relative humidity. The results have a potential value for commercial application in biocontrol agents not only of fire blight but also of other plant diseases. © 2014 The Society for Applied Microbiology.

  11. Freeze-dried EchiTAb+ICP antivenom formulated with sucrose is more resistant to thermal stress than the liquid formulation stabilized with sorbitol.

    Science.gov (United States)

    Herrera, María; Segura, Álvaro; Sánchez, Adriana; Sánchez, Andrés; Vargas, Mariángela; Villalta, Mauren; Harrison, Robert A; Gutiérrez, José María; León, Guillermo

    2017-07-01

    EchiTAb + ICP is a pan-African antivenom used for the treatment of snakebite envenomation in rural sub-Saharan African communities, where the cold chain can be difficult to maintain. To develop a formulation of EchiTAb + ICP that can be distributed and stored without refrigeration, we submitted three different formulations of EchiTAb + ICP: control (i.e. liquid antivenom formulated without stabilizer), liquid antivenom stabilized with sorbitol, and freeze-dried antivenom formulated with sucrose, to an accelerated stability study (i.e. 38 ± 2 °C and 75% relative humidity for 6 months). We analyzed changes in color, residual humidity, reconstitution time (for freeze-dried preparation), pH, osmolality, total protein concentration, antibody monomers content, turbidity, bacterial endotoxins, and pre-clinical neutralizing efficacy of the lethal effect of Echis ocellatus venom at 0, 3 and 6 months. In the control formulation, instability was evidenced by the development of a yellow coloration and an increment in aggregation and turbidity, without change in its neutralizing activity. The sorbitol-stabilized formulation did not develop marked aggregation or turbidity, but instability was evidenced by the development of yellow coloration and a drop in the neutralizing potency. The freeze-dried formulation maintained its neutralizing potency and did not show marked signs of instability, thus indicating that freeze-drying could confer EchiTAb + ICP with improved thermal stability required for distribution and storage at room temperature in sub-Saharan Africa. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Impact of freeze-drying, mixing and horizontal transport on water vapor in the upper troposphere and lower stratosphere (UTLS)

    Science.gov (United States)

    Poshyvailo, Liubov; Ploeger, Felix; Müller, Rolf; Tao, Mengchu; Konopka, Paul; Abdoulaye Diallo, Mohamadou; Grooß, Jens-Uwe; Günther, Gebhard; Riese, Martin

    2017-04-01

    Water vapor in the upper troposphere and lower stratosphere (UTLS) is a key player in the global radiation budget. Therefore, a realistic representation of the water vapor distribution in this region and the involved control processes is critical for climate models, but largely uncertain hitherto. It is known that the extremely low temperatures around the tropical tropopause cause the dominant factor controlling water vapor in the lower stratosphere. Here, we focus on additional processes, such as horizontal transport between tropics and extratropics, small-scale mixing, and freeze-drying. We assess the sensitivities of simulated water vapor in the UTLS from simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS). CLaMS is a Lagrangian transport model, with a parameterization of small-scale mixing (model diffusion) which is coupled to deformations in the large-scale flow. First, to assess the robustness of water vapor with respect to the meteorological datasets we examine CLaMS driven by ECMWF ERA-Interim and the Japanese 55-year reanalysis. Second, to investigate the effects of small-scale mixing we vary the parameterized mixing strength in the CLaMS model between the reference case with the mixing strength optimized to reproduce atmospheric trace gas observations and a purely advective simulation with parameterized mixing turned off. Also calculation of Lagrangian cold points gives further insight of the processes involved. Third, to assess the effects of horizontal transport between the tropics and extratropics we carry out sensitivity simulations with horizontal transport barriers along latitude circles at the equator, 15°N/S and 35°N/S. Finally, the impact of Antarctic dehydration is estimated from additional sensitivity simulations with switched off freeze-drying in the model at high latitudes of 50°N/S. Our results show that the uncertainty in the tropical tropopause temperatures between current reanalysis datasets causes significant

  13. Protein crowding in solution, frozen and freeze-dried states: small-angle neutron and X-ray scattering study of lysozyme/sorbitol/water systems

    Science.gov (United States)

    Krueger, Susan; Khodadadi, Sheila; Clark, Nicholas; McAuley, Arnold; Cristiglio, Viviana; Theyencheri, Narayanan; Curtis, Joseph; Shalaev, Evgenyi

    2015-03-01

    For effective preservation, proteins are often stored as frozen solutions or in glassy states using a freeze-drying process. However, aggregation is often observed after freeze-thaw or reconstitution of freeze-dried powder and the stability of the protein is no longer assured. In this study, small-angle neutron and X-ray scattering (SANS and SAXS) have been used to investigate changes in protein-protein interaction distances of a model protein/cryoprotectant system of lysozyme/sorbitol/water, under representative pharmaceutical processing conditions. The results demonstrate the utility of SAXS and SANS methods to monitor protein crowding at different stages of freezing and drying. The SANS measurements of solution samples showed at least one protein interaction peak corresponding to an interaction distance of ~ 90 Å. In the frozen state, two protein interaction peaks were observed by SANS with corresponding interaction distances at 40 Å as well as 90 Å. On the other hand, both SAXS and SANS data for freeze-dried samples showed three peaks, suggesting interaction distances ranging from ~ 15 Å to 170 Å. Possible interpretations of these interaction peaks will be discussed, as well as the role of sorbitol as a cryoprotectant during the freezing and drying process.

  14. Impact of different cryoprotectants on the survival of freeze-dried Lactobacillus rhamnosus and Lactobacillus casei/paracasei during long-term storage.

    Science.gov (United States)

    Jofré, A; Aymerich, T; Garriga, M

    2015-01-01

    The production of long shelf-life highly concentrated dried probiotic/starter cultures is of paramount importance for the food industry. The aim of the present study was to evaluate the protective effect of glucose, lactose, trehalose, and skim milk applied alone or combined upon the survival of potentially probiotic Lactobacillus rhamnosus CTC1679, Lactobacillus casei/paracasei CTC1677 and L. casei/paracasei CTC1678 during freeze-drying and after 39 weeks of storage at 4 and 22 °C. Immediately after freeze-drying, the percentage of survivors was very high (≥ 94%) and only slight differences were observed among strains and cryoprotectants. In contrast, during storage, survival in the dried state depended on the cryoprotectant, temperature and strain. For all the protectants assayed, the stability of the cultures was remarkably higher when stored under refrigeration (4 °C). Under these conditions, skim milk alone or supplemented with trehalose or lactose showed the best performance (reductions ≤ 0.9 log units after 39 weeks of storage). The lowest survival was observed during non-refrigerated storage and with glucose and glucose plus milk; no viable cells left at the end of the storage period. Thus, freeze-drying in the presence of appropriate cryoprotectants allows the production of long shelf-life highly concentrated dried cultures ready for incorporation in high numbers into food products as starter/potential probiotic cultures.

  15. Water activity-temperature state diagrams of freeze-dried Lactobacillus acidophilus (La-5): influence of physical state on bacterial survival during storage.

    Science.gov (United States)

    Kurtmann, Lone; Carlsen, Charlotte U; Skibsted, Leif H; Risbo, Jens

    2009-01-01

    Water activity-temperature state diagrams for Lactobacillus acidophilus freeze-dried in a sucrose or a lactose matrix were established based on determination of stabilized glass transition temperatures by differential scanning calorimetry during equilibration with respect to water activity at fixed temperatures. The bacteria in the lactose matrix had higher stabilized glass transition temperatures for all a(w) investigated. The survival of Lactobacillus acidophilus determined as colony forming units for up to 10 weeks of storage at 20 degrees C for (i) a(w) = 0.11 with both freeze-dried matrices in the glassy state, (ii) a(w) = 0.23 with the bacteria in the lactose matrix in a glassy state but with the bacteria in sucrose matrix in the nonglassy state, and (iii) a(w) = 0.43 with both freeze-dried matrices in a nonglassy state showed that the nature of the sugar was more important for storage stability than the physical state of the matrix with the nonreducing sucrose providing better stability than the reducing lactose.

  16. Phase formation of V2O5.xNb2O5 compounds via gels and freeze-dried precursors

    International Nuclear Information System (INIS)

    Langbein, Hubert; Mayer-Uhma, Tobias

    2009-01-01

    An X-ray powder diffraction study of the phase formation in the system V 2 O 5 /Nb 2 O 5 is performed. Freeze-dried ammonium vanadate and ammonium oxalato niobate, alkoxide-derived xerogels and a mixture of active oxides are used as precursors to compare the resulting phase composition. Thermal decomposition of the freeze-dried precursor is monitored with DTA/TG and mass spectrometry. In the quasi-binary system V 2 O 5 -Nb 2 O 5 metastable VNbO 5 , V 4 Nb 18 O 55 , VNb 9 O 25 and solid solutions of V 2 O 5 in TT-Nb 2 O 5 as also thermodynamically stable VNb 9 O 25 exist. The thermal decomposition of freeze-dried vanadate-oxalatoniobate solution allows the synthesis of all these phases in a relative simple manner. Structural relationships between an intermediate phase and the product, or, in the case of solid-state reactions, between one of the starting oxide and the product, favour the desired reaction. Therefore, the structure of a former phase influences or directs the structure of the product similar to a topotactic reaction

  17. Freeze-Drying From Organic Cosolvent Systems, Part 1: Thermal Analysis of Cosolvent-Based Placebo Formulations in the Frozen State.

    Science.gov (United States)

    Kunz, Claudia; Schuldt-Lieb, Sonja; Gieseler, Henning

    2018-03-01

    The use of cosolvent systems has been demonstrated to shorten lengthy freeze-drying processes and improve the solubility and stability of certain active pharmaceutical ingredients. The goal of the present study was to evaluate the suitability of 2 thermal characterization techniques, differential scanning calorimetry and freeze-dry microscopy, and to identify an optimal cosolvent system. Binary mixtures of a cosolvent (tert-butanol, dimethyl sulfoxide, 1,4-dioxane, acetone, or ethanol) and water were investigated. Ternary mixtures of frequently used excipients (50 mg/g mannitol, sucrose, glycine, or polyvinylpyrrolidone [PVP]) and a solvent-water system were then analyzed for their thermal properties. PVP presented a particularly high glass transition temperature (T g ') in 70% tert-butanol at -17.9°C. Large needle-shaped crystals that have been shown to be associated with improved processability were observed with mannitol and PVP in 40% 1,4-dioxane. A heterogeneous sublimation rate of the solvent and water whose impact on product stability remained unclear was observed with PVP in 40% 1,4-dioxane. Freeze-dry microscopy analysis demonstrated a possible extension of the process time for PVP in 99% dimethyl sulfoxide due to a slowly moving sublimation front. Conceivable negative consequences and the need for special treatment for low-melting cosolvents, such as ethanol and acetone, were predicted and discussed. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  18. PHBV/PLLA-based composite scaffolds fabricated using an emulsion freezing/freeze-drying technique for bone tissue engineering: surface modification and in vitro biological evaluation

    International Nuclear Information System (INIS)

    Sultana, Naznin; Wang Min

    2012-01-01

    Tissue engineering combines living cells with biodegradable materials and/or bioactive components. Composite scaffolds containing biodegradable polymers and nanosized osteoconductive bioceramic with suitable properties are promising for bone tissue regeneration. In this paper, based on blending two biodegradable and biocompatible polymers, namely poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and poly(l-lactic acid) (PLLA) with incorporated nano hydroxyapatite (HA), three-dimensional composite scaffolds with controlled microstructures and an interconnected porous structure, together with high porosity, were fabricated using an emulsion freezing/freeze-drying technique. The influence of various parameters involved in the emulsion freezing/freeze-drying technique was studied for the fabrication of good-quality polymer scaffolds based on PHBV polymers. The morphology, mechanical properties and crystallinity of PHBV/PLLA and HA in PHBV/PLLA composite scaffolds and PHBV polymer scaffolds were studied. The scaffolds were coated with collagen in order to improve wettability. During in vitro biological evaluation study, it was observed that SaOS-2 cells had high attachment on collagen-coated scaffolds. Significant improvement in cell proliferation and alkaline phosphatase activity for HA-incorporated composite scaffolds was observed due to the incorporation of HA. After 3 and 7 days of culture on all scaffolds, SaOS-2 cells also had normal morphology and growth. These results indicated that PHBV/PLLA-based scaffolds fabricated via an emulsion freezing/freeze-drying technique were favorable sites for osteoblastic cells and are promising for the applications of bone tissue engineering.

  19. Evaluation of manometric temperature measurement (MTM), a process analytical technology tool in freeze drying, part III: heat and mass transfer measurement.

    Science.gov (United States)

    Tang, Xiaolin Charlie; Nail, Steven L; Pikal, Michael J

    2006-01-01

    This article evaluates the procedures for determining the vial heat transfer coefficient and the extent of primary drying through manometric temperature measurement (MTM). The vial heat transfer coefficients (Kv) were calculated from the MTM-determined temperature and resistance and compared with Kv values determined by a gravimetric method. The differences between the MTM vial heat transfer coefficients and the gravimetric values are large at low shelf temperature but smaller when higher shelf temperatures were used. The differences also became smaller at higher chamber pressure and smaller when higher resistance materials were being freeze-dried. In all cases, using thermal shields greatly improved the accuracy of the MTM Kv measurement. With use of thermal shields, the thickness of the frozen layer calculated from MTM is in good agreement with values obtained gravimetrically. The heat transfer coefficient "error" is largely a direct result of the error in the dry layer resistance (ie, MTM-determined resistance is too low). This problem can be minimized if thermal shields are used for freeze-drying. With suitable use of thermal shields, accurate Kv values are obtained by MTM; thus allowing accurate calculations of heat and mass flow rates. The extent of primary drying can be monitored by real-time calculation of the amount of remaining ice using MTM data, thus providing a process analytical tool that greatly improves the freeze-drying process design and control.

  20. Robustness testing in pharmaceutical freeze-drying: inter-relation of process conditions and product quality attributes studied for a vaccine formulation.

    Science.gov (United States)

    Schneid, Stefan C; Stärtzel, Peter M; Lettner, Patrick; Gieseler, Henning

    2011-01-01

    The recent US Food and Drug Administration (FDA) legislation has introduced the evaluation of the Design Space of critical process parameters in manufacturing processes. In freeze-drying, a "formulation" is expected to be robust when minor deviations of the product temperature do not negatively affect the final product quality attributes. To evaluate "formulation" robustness by investigating the effect of elevated product temperature on product quality using a bacterial vaccine solution. The vaccine solution was characterized by freeze-dry microscopy to determine the critical formulation temperature. A conservative cycle was developed using the SMART™ mode of a Lyostar II freeze dryer. Product temperature was elevated to imitate intermediate and aggressive cycle conditions. The final product was analyzed using X-ray powder diffraction (XRPD), scanning electron microscopy (SEM), Karl Fischer, and modulated differential scanning calorimetry (MDSC), and the life cell count (LCC) during accelerated stability testing. The cakes processed at intermediate and aggressive conditions displayed larger pores with microcollapse of walls and stronger loss in LCC than the conservatively processed product, especially during stability testing. For all process conditions, a loss of the majority of cells was observed during storage. For freeze-drying of life bacterial vaccine solutions, the product temperature profile during primary drying appeared to be inter-related to product quality attributes.

  1. Determination of orthodontic tooth movement and tissue reaction following demineralized freeze-dried bone allograft grafting intervention

    Directory of Open Access Journals (Sweden)

    Massoud Seifi

    2012-01-01

    Full Text Available Background: Socket preservation after tooth extraction is one of the indications of bone grafting to enhance preorthodontic condition. The aim of this study is to determine the effects of socket preservation on the immediate tooth movement, alveolar ridge height preservation and orthodontic root resorption. Materials and Methods: In a split-mouth technique, twelve sites in three dogs were investigated as an experimental study. Crushed demineralized freeze-dried bone allograft (DFDBA (CenoBone® was used as the graft material. The defects were made by the extraction of 3 rd premolar. On one side of each jaw, the defects were preserved by DFDBA and defects of the other side left opened as the control group. Simultaneously the teeth adjacent to the defects were pulled together by a NiTi coil spring. After eight weeks, the amount of (OTM, alveolar height, and root resorption were measured. Analysis of variance was used for purpose of comparison. Results: There was a slight increase in OTM at grafted sites as they were compared to the control sites (P<0.05. Also a significant bone resorption in control site and successful socket preservation in experimental site were observed. Reduction of root resorption at the augmented site was significant compared to the normal healing site (P<0.05. Conclusion: Using socket preservation, tooth movement can be immediately started without waiting for the healing of the recipient site. This can provide some advantages like enhanced rate of OTM, its approved effects on ridge preservation that reduces the chance of dehiscence and the reduction of root resorption.

  2. Antioxidant capacity and other bioactivities of the freeze-dried Amazonian palm berry, Euterpe oleraceae mart. (acai).

    Science.gov (United States)

    Schauss, Alexander G; Wu, Xianli; Prior, Ronald L; Ou, Boxin; Huang, Dejian; Owens, John; Agarwal, Amit; Jensen, Gitte S; Hart, Aaron N; Shanbrom, Edward

    2006-11-01

    The fruit of Euterpe oleraceae, commonly known as acai, has been demonstrated to exhibit significantly high antioxidant capacity in vitro, especially for superoxide and peroxyl scavenging, and, therefore, may have possible health benefits. In this study, the antioxidant capacities of freeze-dried acai fruit pulp/skin powder (OptiAcai) were evaluated by different assays with various free radical sources. It was found to have exceptional activity against superoxide in the superoxide scavenging (SOD) assay, the highest of any food reported to date against the peroxyl radical as measured by the oxygen radical absorbance capacity assay with fluorescein as the fluorescent probe (ORACFL), and mild activity against both the peroxynitrite and hydroxyl radical by the peroxynitrite averting capacity (NORAC) and hydroxyl radical averting capacity (HORAC) assays, respectively. The SOD of acai was 1614 units/g, an extremely high scavenging capacity for O2*-, by far the highest of any fruit or vegetable tested to date. Total phenolics were also tested as comparison. In the total antioxidant (TAO) assay, antioxidants in acai were differentiated into "slow-acting" and "fast-acting" components. An assay measuring inhibition of reactive oxygen species (ROS) formation in freshly purified human neutrophils showed that antioxidants in acai are able to enter human cells in a fully functional form and to perform an oxygen quenching function at very low doses. Furthermore, other bioactivities related to anti-inflammation and immune functions were also investigated. Acai was found to be a potential cyclooxygenase (COX)-1 and COX-2 inhibitor. It also showed a weak effect on lipopolysaccharide (LPS)-induced nitric oxide but no effect on either lymphocyte proliferation and phagocytic capacity.

  3. Determination of orthodontic tooth movement and tissue reaction following demineralized freeze-dried bone allograft grafting intervention.

    Science.gov (United States)

    Seifi, Massoud; Ghoraishian, Seyed Ahmad

    2012-03-01

    Socket preservation after tooth extraction is one of the indications of bone grafting to enhance preorthodontic condition. The aim of this study is to determine the effects of socket preservation on the immediate tooth movement, alveolar ridge height preservation and orthodontic root resorption. In a split-mouth technique, twelve sites in three dogs were investigated as an experimental study. Crushed demineralized freeze-dried bone allograft (DFDBA) (CenoBone(®)) was used as the graft material. The defects were made by the extraction of 3(rd) premolar. On one side of each jaw, the defects were preserved by DFDBA and defects of the other side left opened as the control group. Simultaneously the teeth adjacent to the defects were pulled together by a NiTi coil spring. After eight weeks, the amount of (OTM), alveolar height, and root resorption were measured. Analysis of variance was used for purpose of comparison. There was a slight increase in OTM at grafted sites as they were compared to the control sites (P<0.05). Also a significant bone resorption in control site and successful socket preservation in experimental site were observed. Reduction of root resorption at the augmented site was significant compared to the normal healing site (P<0.05). Using socket preservation, tooth movement can be immediately started without waiting for the healing of the recipient site. This can provide some advantages like enhanced rate of OTM, its approved effects on ridge preservation that reduces the chance of dehiscence and the reduction of root resorption.

  4. Spectroscopic investigation of the aggregation state of amphotericin B during loading, freeze-drying, and reconstitution of polymeric micelles.

    Science.gov (United States)

    Adams, Monica; Kwon, Glen S

    2004-11-22

    To investigate the relative aggregation state of amphotericin B (AmB) during loading and reconstitution of polymeric micelles. Hexanoate and stearate derivatives of PEO-b-p (L-Asp) were prepared. The polymers and AmB were dissolved in methanol (MeOH). Milli-Q water was then added slowly, and the MeOH was removed via rotary evaporation. The solutions were freeze-dried in the presence of trehalose. During micelle preparation, the aggregation state of AmB was assessed using absorption spectroscopy. Upon reconstitution, the samples were analyzed using vapor-pressure osmometry, size-exclusion chromatography (SEC), and absorption spectroscopy. The absorption spectrum of AmB in the presence of the block copolymers was compared to that of AmB alone under the same conditions. AmB was loaded into micelles prepared from acyl derivatives of PEO-b-p (L-Asp). Absorption spectroscopy indicated that the aggregation state was preserved during the loading process. AmB exists in a self-aggregated state in polymeric micelles containing hexanoate ester cores and in a relatively monomeric state in polymeric micelles containing stearate ester cores. Vapor-pressure osmometry confirmed the isotonicity of the formulations, while SEC indicated that the micelles were approximately 10(6) g/mol. Depending on the polymer structure and assembly conditions, it is possible to encapsulate AmB in a relatively nonaggregated or aggregated state in micelles prepared from acyl derivatives of PEO-b-p (L-Asp). In polymeric micelles containing stearate side chains, AmB was loaded in a nearly monomeric state, possibly due to interaction with the stearate side chains. The final aggregation state of the drug is preserved during lyophilization and reconstitution of polymeric micelles prepared by a novel solvent evaporation procedure.

  5. A clinical and histomorphometric study of calcium sulfate compared with freeze-dried bone allograft for alveolar ridge preservation.

    Science.gov (United States)

    Toloue, Samira M; Chesnoiu-Matei, Ioana; Blanchard, Steven B

    2012-07-01

    Many materials have been found to be effective in ridge preservation. The purpose of this study is to determine whether calcium sulfate (CS) is as effective as freeze-dried bone allograft (FDBA) in preserving postextraction ridge dimensions and to evaluate the amount of new bone formation and graft clearance through histologic analysis. Thirty-one extraction sites were selected. Postextraction clinical measurements were made, and sites were divided randomly into the test group (CS) or the control group (FDBA). After graft placement, all individuals received the same postoperative treatment and instructions. Participants were recalled after 3 months, measurements were made, and sites were re-entered. Bone samples were harvested and analyzed with histologic methodology for new bone formation and remaining residual graft. Thirteen test and 15 control sites were evaluated. There was no significant change in vertical ridge height before or after surgery within the test and control groups (P = 0.57, P = 0.68, respectively). There was a significant decrease in bucco-lingual ridge width for both groups (P = 0.0003, P = 0.0075, respectively), but the difference between groups was not significant (P = 0.11). Histologic analysis revealed an average of 32% new bone formation with 2.5% graft remaining for the test group and 16.7% new bone formation with 21% graft remaining for the control. Results indicate that CS is as effective as FDBA in preserving postextraction ridge dimensions in non-molar extraction sites. There is greater clearance of CS with more new bone formation after ≈3 months compared with FDBA in these sites. This paper received the Maynard K. Hine Award for Excellence in Dental Research presented by the Indiana Section of the American Association for Dental Research and supported by Procter & Gamble.

  6. Evaluation of spray and freeze dried excipient bases containing disintegration accelerators for the formulation of metoclopramide orally disintegrating tablets

    International Nuclear Information System (INIS)

    Alanazi, Fars K.

    2007-01-01

    Orally disintegrating tablets (ODT) are gaining attractiveness over conventional tablets especially for patients having difficulty in swallowing such as pediatric, geriatric, bedridden and disable patients. ODT technologies render the tablets disintegrate in the mouth without chewing or additional water intake. So far there have been many patents for ODT, but only few publications are dealing with this dosage form. The aim of the present study was to formulate metoclopramide in ODT with sufficient mechanical strength and fast disintegration from bases prepared by both spray (SD) and freeze drying (FD) techniques. Different disintegration accelerators (DA) were utilized to prepare proper ODT using various super-disintegrants (Ac-Di-Sol, Kollidon and Sodium Starch glycolate), a volatilizing solvent (ethanol) and an amino acid (glycine). Metoclopramide, an antiemetic medication, was used a model drug in the formulated ODT. It was noted that the disintegration of ODT depends on utilization of DA in both SD and FD techniques to prepare tablet bases for ODT and so many other factors such as drying processes. The good disintegration property of the prepared tablets was related to the excellent wettability of the ingredients after being subjected to the drying processes. Results also showed that the addition of DA to the tablet bases before drying process results in lengthening of the disintegration time in comparison to their addition to the tablet bases after the drying process. Those findings be utilized for many drugs and they may be considered versatile in their applications. Also, the disintegration of the ODT in the buccal cavity may favor fast absorption via the mucus membrane in the oral cavity. (author)

  7. Comparing the acidities of aqueous, frozen, and freeze-dried phosphate buffers: Is there a "pH memory" effect?

    Science.gov (United States)

    Vetráková, Ľubica; Vykoukal, Vít; Heger, Dominik

    2017-09-15

    The concept of "pH memory" has been established in the literature for the correlation between the pH of a pre-lyophilization solution and the ionization state of freeze-dried powder (lyophile). In this paper, the concept of "pH memory" is explored for the system of an aqueous solution, a frozen solution, and a lyophile. Sodium and potassium phosphate buffers in the pH range of 5-9 were frozen and lyophilized with sulfonephthalein indicators as acidity probes, and their Hammett acidity functions were compared to the initial pH of the aqueous solution. The results show that the acidities of the lyophiles are somewhat changed compared to the initial pHs, but the acidities in the frozen state differ more substantially. The Hammett acidity functions of the frozen buffers were found to be markedly dissimilar from the initial pH, especially in the sodium phosphate frozen at 233K, where an increase in the initial pH led to a decrease in the Hammett acidity function of the frozen state at a certain pH range. The large acidification observed after freezing the sodium phosphate buffer was not detected in the lyophiles after the sample had been dried; the phenomenon is explained considering the formed crystals analyzed by X-ray powder diffraction. The results suggest that monitoring the final acidity of a lyophile is not sufficient to predict all the acidity changes throughout the whole lyophilization process. The importance of well-controlled freezing and lyophilization conditions follows from the results of the research. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Strategies for multivariate modeling of moisture content in freeze-dried mannitol-containing products by near-infrared spectroscopy.

    Science.gov (United States)

    Yip, Wai Lam; Gausemel, Ingvil; Sande, Sverre Arne; Dyrstad, Knut

    2012-11-01

    Accurate determination of residual moisture content of a freeze-dried (FD) pharmaceutical product is critical for prediction of its quality. Near-infrared (NIR) spectroscopy is a fast and non-invasive method routinely used for quantification of moisture. However, several physicochemical properties of the FD product may interfere with absorption bands related to the water content. A commonly used stabilizer and bulking agent in FD known for variation in physicochemical properties, is mannitol. To minimize this physicochemical interference, different approaches for multivariate correlation between NIR spectra of a FD product containing mannitol and the corresponding moisture content measured by Karl Fischer (KF) titration have been investigated. A novel method, MIPCR (Main and Interactions of Individual Principal Components Regression), was found to have significantly increased predictive ability of moisture content compared to a traditional PLS approach. The philosophy behind the MIPCR is that the interference from a variety of particle and morphology attributes has interactive effects on the water related absorption bands. The transformation of original wavelength variables to orthogonal scores gives a new set of variables (scores) without covariance structure, and the possibility of inclusion of interaction terms in the further modeling. The residual moisture content of the FD product investigated is in the range from 0.7% to 2.6%. The mean errors of cross validated prediction of models developed in the investigated NIR regions were reduced from a range of 24.1-27.6% for traditional PLS method to 15.7-20.5% for the MIPCR method. Improved model quality by application of MIPCR, without the need for inclusion of a large number of calibration samples, might increase the use of NIR in early phase product development, where availability of calibration samples is often limited. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. On the effect of ultrasound-assisted atmospheric freeze-drying on the antioxidant properties of eggplant.

    Science.gov (United States)

    Colucci, Domenico; Fissore, Davide; Rossello, Carmen; Carcel, Juan A

    2018-04-01

    The low operating temperatures employed in atmospheric freeze-drying permits an effective drying of heat sensitive products, without any impairment of their quality attributes. When using power ultrasound, the drying rate can be increased, thus reducing the process duration. However, ultrasound can also affect the product quality. The aim of this study was to evaluate the effect of various drying process variables, namely air temperature and velocity, ultrasound power and sample size, on the antioxidant properties of eggplant (Solanum melongena L.) samples. For this reason, drying experiments were carried out at different drying temperatures (-5, -7.5, -10 °C), power ultrasound levels (0, 25, 50 W; 21.9 kHz) and air velocities (2, 5 m s -1 ) using different sample sizes (8.8 mm and 17.6 mm cube side). The ascorbic acid content (Jagota and Dani method), total phenolic content (Folin-Ciocalteau method), and the antioxidant capacity (FRAP method) of the dried products were considered as quality indicators of the dried samples. The increase in air velocity and temperature, as well as the sample size, significantly reduced the antioxidant potential of the dried samples (p-value < .05). For a given sample size, the application of ultrasound, at the acoustic power levels tested, did not produce significant effects on the antioxidant indicators considered. Temperature measurements inside the drying sample showed a non-negligible temperature rise when acoustic power was applied. Copyright © 2018. Published by Elsevier Ltd.

  10. Socket preservation using demineralized freezed dried bone allograft with and without plasma rich in growth factor: A canine study

    Directory of Open Access Journals (Sweden)

    Ahmad Mogharehabed

    2014-01-01

    Full Text Available Background: The accelerating effect of plasma rich in growth factors (PRGFs in the healing of extraction sockets has been demonstrated by some studies. The aim of the present study was to histologically and histomorphometrically evaluate whether bone formation would increase by the combined use of PRGF and demineralized freeze-dried bone allograft (DFDBA. Materials and Methods: In four female dogs, the distal root of the second, third and fourth lower premolars were extracted bilaterally and the mesial roots were preserved. The extraction sockets were randomly divided into DFDBA + PRGF, DFDBA + saline or control groups. Two dogs were sacrificed after 2 weeks and two dogs were sacrificed after 6 weeks. The extraction sockets were evaluated from both histological and histomorphometrical aspects. The data were analyzed by Mann-Whitney followed by Kruskal-Wallis tests using the Statistical Package for the Social Sciences version 20 (SPSS Inc., Chicago, IL, USA. Significant levels were set at 0.05. Results: The least decrease in socket height was observed in the DFDBA + PRGF group (0.73 ± 0.42 mm. The least decrease in the coronal portion was observed in the DFDBA + PRGF group (1.38 ± 1.35 mm². The least decrease in the middle surface was observed in the DFDBA group (0.61 ± 0.80 mm². The least decrease in the apical portion was observed in the DFDBA group (0.34 ± 0.39 mm². Conclusion: The present study showed better socket preservation subsequent to the application of DFDBA and PRGF combination in comparison with the two other groups. However, the difference was not statistically significant.

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

    Science.gov (United States)

    Schiffter, Heiko; Condliffe, Jamie; Vonhoff, Sebastian

    2010-08-06

    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 (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

  12. Application of Freeze-Dried Powders of Genetically Engineered Microbial Strains as Adsorbents for Rare Earth Metal Ions.

    Science.gov (United States)

    Moriwaki, Hiroshi; Masuda, Reiko; Yamazaki, Yuki; Horiuchi, Kaoru; Miyashita, Mari; Kasahara, Jun; Tanaka, Tatsuhito; Yamamoto, Hiroki

    2016-10-12

    The adsorption behaviors of the rare earth metal ions onto freeze-dried powders of genetically engineered microbial strains were compared. Cell powders obtained from four kinds of strains, Bacillus subtilis 168 wild type (WT), lipoteichoic acid-defective (ΔLTA), wall teichoic acid-defective (ΔWTA), and cell wall hydrolases-defective (EFKYOJLp) strains, were used as an adsorbent of the rare earth metal ions at pH 3. The adsorption ability of the rare earth metal ions was in the order of EFKYOJLp > WT > ΔLTA > ΔWTA. The order was the same as the order of the phosphorus quantity of the strains. This result indicates that the main adsorption sites for the ions are the phosphate groups and the teichoic acids, LTA and WTA, that contribute to the adsorption of the rare earth metal ions onto the cell walls. The contribution of WTA was clearly greater than that of LTA. Each microbial powder was added to a solution containing 16 kinds of rare earth metal ions, and the removals (%) of each rare earth metal ion were obtained. The scandium ion showed the highest removal (%), while that of the lanthanum ion was the lowest for all the microbial powders. Differences in the distribution coefficients between the kinds of lanthanide ions by the EFKYOJLp and ΔWTA powders were greater than those of the other strains. Therefore, the EFKYOJLp and ΔWTA powders could be applicable for the selective extraction of the lanthanide ions. The ΔLTA powder coagulated by mixing with a rare earth metal ion, although no sedimentation of the WT or ΔWTA powder with a rare earth metal ion was observed under the same conditions. The EFKYOJLp powder was also coagulated, but its flocculating activity was lower than that of ΔLTA. The ΔLTA and EFKYOJLp powders have a long shape compared to those of the WT or ΔWTA strain. The shapes of the cells will play an important role in the sedimentation of the microbial powders with rare earth metal ions. As the results, three kinds of the genetically

  13. Effects of hot air and freeze drying methods on antioxidant activity, colour and some nutritional characteristics of strawberry tree (Arbutus unedo L) fruit.

    Science.gov (United States)

    Orak, H H; Aktas, T; Yagar, H; İsbilir, S Selen; Ekinci, N; Sahin, F Hasturk

    2012-08-01

    Antioxidant activity, colour and some nutritional properties of hot air and freeze-dried strawberry tree (Arbutus unedo L.) fruits were investigated. Additionally, the effects of two pre-treatments, namely ethyl oleate and water blanching, were compared in terms of drying characteristics. For determination of antioxidant activities in ethanol extracts, two different analytical methods were used: 1,1-diphenyl-2-picrylhydrazyl scavenging activity and β-carotene bleaching activity. As a result, the ethyl oleate pre-treatment shortened the drying time by hot air method and gave a higher 1,1-diphenyl-2-picrylhydrazyl scavenging activity (82.16 ± 0.34%), total phenolic content (7.62 ± 1.09 µg GAE/g extract), ascorbic acid content (236.93 ± 20.14 mg/100 g), besides hydromethylfurfural was not observed. Freeze-dried fruits exhibited higher ascorbic acid content (368.63 ± 17.16 mg/100 g) than those fresh fruits (231.33 ± 19.51 mg/100 g) and nearly 1,1-diphenyl-2-picrylhydrazyl activity (93.52 ± 0.41 %) to fresh fruits (94.03 ± 1.18%). Colour characteristics, sugar content and mineral contents of fruits were significantly affected by pre-treatments and drying methods (p fruits should bring a valuable and attractive foodstuff to food industry due to the rich nutritional components, antioxidant activity and colour. Another conclusion from this study is that the freeze-drying is the best drying method to keep the nutritional value, antioxidant activity and sensory properties of fruits.

  14. Freeze-dried plasma enhances clot formation and inhibits fibrinolysis in the presence of tissue plasminogen activator similar to pooled liquid plasma.

    Science.gov (United States)

    Huebner, Benjamin R; Moore, Ernest E; Moore, Hunter B; Sauaia, Angela; Stettler, Gregory; Dzieciatkowska, Monika; Hansen, Kirk; Banerjee, Anirban; Silliman, Christopher C

    2017-08-01

    Systemic hyperfibrinolysis is an integral part of trauma-induced coagulopathy associated with uncontrolled bleeding. Recent data suggest that plasma-first resuscitation attenuates hyperfibrinolysis; however, the availability, transport, storage, and administration of plasma in austere environments remain challenging and have limited its use. Freeze-dried plasma (FDP) is a potential alternative due to ease of storage, longer shelf life, and efficient reconstitution. FDP potentially enhances clot formation and resists breakdown better than normal saline (NS) and albumin and similar to liquid plasma. Healthy volunteers underwent citrated blood draw followed by 50% dilution with NS, albumin, pooled plasma (PP), or pooled freeze-dried plasma (pFDP). Citrated native and tissue plasminogen activator (t-PA)-challenge (75 ng/mL) thrombelastography were done. Proteins in PP, pFDP, and albumin were analyzed by mass spectroscopy. pFDP and PP had superior clot-formation rates (angle) and clot strength (maximum amplitude) compared with NS and albumin in t-PA-challenge thrombelastographies (angle: pFDP, 67.9 degrees; PP, 67.8 degrees; NS, 40.6 degrees; albumin, 35.8 degrees; maximum amplitude: pFDP, 62.4 mm; PP, 63.5 mm; NS, 44.8 mm; albumin, 41.1 mm). NS and albumin dilution increased susceptibility to t-PA-induced hyperfibrinolysis compared with pFDP and PP (NS, 62.4%; albumin, 62.6%; PP, 8.5%; pFDP, 6.7%). pFDP was similar to PP in the attenuation of t-PA-induced fibrinolysis. Most proteins (97%) were conserved during the freeze-dry process, with higher levels in 12% of pFDP proteins compared with PP. pFDP enhances clot formation and attenuates hyperfibrinolysis better than NS and albumin and is a potential alternative to plasma resuscitation in the treatment of hemorrhagic shock. © 2017 AABB.

  15. Effect of baking and steaming on physicochemical and thermal properties of sweet potato puree preserved by freezing and freeze-drying

    Directory of Open Access Journals (Sweden)

    Bernarda Svrakačić

    2016-01-01

    Full Text Available Thermal treatments could be one of the hurdles in applications of sweet potato purees for food different products formulation. Sweet potato purees (SPP were prepared from raw, baked and steamed roots and they were preserved by freezing and freeze-drying. The effects of baking and steaming on thermal properties (melting temperature-Tm, melting transition energy - ΔH, and glass transition temperatures - Tg of sweet potato (cultivar Beauregard, were measured by means of a Differential scanning calorimetry (DSC. The SPP made from baked roots had higher total and soluble solids (20.32 and 18.95%, respectively than SPP made from raw and steamed roots. It can be also noticed that starch content was reduced by steaming and baking which reflected on amount of total and reducing sugars. The increase of reducing sugars level in baked SPP for 3.78% and steamed for 0.86% SPP was the result of yielding the maltose. The chemical changes of SPP also influenced the thermal behavior such that SPP prepared from baked sweet potato roots had the lowest initial freezing point (-2.80 °C followed by SPP prepared from steamed (-2.63 °C and raw (-0.71 °C roots. The highest energy for melting (transition was needed for SPP prepared from raw potato roots followed by steamed and baked roots, -103.79, -103.63, and -102.90 J/g, respectively. The glass transition in freeze-dried SPP prepared from raw roots was not detected. However, in the freeze-dried SPP prepared from baked and steamed roots the glass transition was detected in the range of 39 and 42 °C but with no significant difference (p > 0.05.

  16. Application of Optical Coherence Tomography Freeze-Drying Microscopy for Designing Lyophilization Process and Its Impact on Process Efficiency and Product Quality.

    Science.gov (United States)

    Korang-Yeboah, Maxwell; Srinivasan, Charudharshini; Siddiqui, Akhtar; Awotwe-Otoo, David; Cruz, Celia N; Muhammad, Ashraf

    2018-01-01

    Optical coherence tomography freeze-drying microscopy (OCT-FDM) is a novel technique that allows the three-dimensional imaging of a drug product during the entire lyophilization process. OCT-FDM consists of a single-vial freeze dryer (SVFD) affixed with an optical coherence tomography (OCT) imaging system. Unlike the conventional techniques, such as modulated differential scanning calorimetry (mDSC) and light transmission freeze-drying microscopy, used for predicting the product collapse temperature (Tc), the OCT-FDM approach seeks to mimic the actual product and process conditions during the lyophilization process. However, there is limited understanding on the application of this emerging technique to the design of the lyophilization process. In this study, we investigated the suitability of OCT-FDM technique in designing a lyophilization process. Moreover, we compared the product quality attributes of the resulting lyophilized product manufactured using Tc, a critical process control parameter, as determined by OCT-FDM versus as estimated by mDSC. OCT-FDM analysis revealed the absence of collapse even for the low protein concentration (5 mg/ml) and low solid content formulation (1%w/v) studied. This was confirmed by lab scale lyophilization. In addition, lyophilization cycles designed using Tc values obtained from OCT-FDM were more efficient with higher sublimation rate and mass flux than the conventional cycles, since drying was conducted at higher shelf temperature. Finally, the quality attributes of the products lyophilized using Tc determined by OCT-FDM and mDSC were similar, and product shrinkage and cracks were observed in all the batches of freeze-dried products irrespective of the technique employed in predicting Tc.

  17. Survival rate of Saccharomyces boulardii adapted to a functional freeze-dried yoghurt, related to processing, storage and digestion by experimental Wistar rats

    Directory of Open Access Journals (Sweden)

    Eunice Tranquilino-Rodriguez

    2017-02-01

    Full Text Available Background: Saccharomycesboulardiiis a probiotic clinically effective inthe prevention and treatment of antibiotic induced diarrheain both children and adults, Clostridium difficile infections, inflammatory bowel disease, and other gastrointestinal disorders. However, the microorganisms need to survive the gastrointestinal transit and arrive to their action site alive in order to exert their beneficial effects. Microencapsulation is an alternative to improve the viability of probiotic in foods which can also survive in the gastrointestinal conditions. Freeze--drying is a method of dehydration that does not affect nutrients and bioactive compounds,such as probiotics contained in foods.All of them will increase the survival rate of S.boulardii.Purpose of this study:This study focused on formulae freeze-dried yogurt containing inulin, vegetable palm oil,and S.boulardii, both asfree cells and in microencapsulated form.Also,the effect of ampicillin associated S.boulardii. Methods. Yogurts were given to an “in vivo” digestion process, using male Wistar rats.The survival of S. boulardiiwas subsequently evaluated in colon and feces.For this study, six treatmentsof four of rats were used:i control rats ii rats fed with yogurt containing S. boulardiias free cells, iii rats fed with yogurt containing S. boulardiiinmicro-encapsulated form, iv control rats fed with penicillin,v rats fed with ampicillin plus yogurtcontaining S. boulardiias free cells, and vi rats fed with penicillin plus yogurt containing S. boulardiiin micro-encapsulated form. Results:The study demonstrated it was feasible to freeze-drythe S. boulardiiand incorporate it into a yogurtmade with skim milk,inulin, and unsaturated vegetable oil.The freeze-drying process not affected thesurvival of the S. boulardii(p<0.05. Microencapsulation increased the survival of S. boulardii on 1.77-Log CFU/g, and the presence of S. boulardii was only detected in colon and fecesof those rats which

  18. Balancing mechanical strength with bioactivity in chitosan-calcium phosphate 3D microsphere scaffolds for bone tissue engineering: air- vs. freeze-drying processes.

    Science.gov (United States)

    Nguyen, D T; McCanless, J D; Mecwan, M M; Noblett, A P; Haggard, W O; Smith, R A; Bumgardner, J D

    2013-01-01

    The objective of this study was to evaluate the potential benefit of 3D composite scaffolds composed of chitosan and calcium phosphate for bone tissue engineering. Additionally, incorporation of mechanically weak lyophilized microspheres within those air-dried (AD) was considered for enhanced bioactivity. AD microsphere, alone, and air- and freeze-dried microsphere (FDAD) 3D scaffolds were evaluated in vitro using a 28-day osteogenic culture model with the Saos-2 cell line. Mechanical testing, quantitative microscopy, and lysozyme-driven enzymatic degradation of the scaffolds were also studied. FDAD scaffold showed a higher concentration (p mechanical strength was sacrificed through introduction of the less stiff, porous FD spheres.

  19. A botanical containing freeze dried açai pulp promotes healthy aging and reduces oxidative damage in sod1 knockdown flies

    OpenAIRE

    Laslo, Mara; Sun, Xiaoping; Hsiao, Cheng-Te; Wu, Wells W.; Shen, Rong-Fong; Zou, Sige

    2012-01-01

    Superoxide dismutase 1 (SOD1), a critical enzyme against oxidative stress, is implicated in aging and degenerative diseases. We previously showed that a nutraceutical containing freeze-dried açai pulp promotes survival of flies fed a high-fat diet or sod1 knockdown flies fed a standard diet. Here, we investigated the effect of açai supplementation initiated at the early or late young adulthood on lifespan, physiological function, and oxidative damage in sod1 knockdown flies. We found that Aça...

  20. Comparative study of two drying techniques used in radioactive source preparation: Freeze-drying and evaporation using hot dry nitrogen jets

    International Nuclear Information System (INIS)

    Branger, T.; Bobin, C.; Iroulart, M.-G.; Lepy, M.-C.; Le Garreres, I.; Morelli, S.; Lacour, D.; Plagnard, J.

    2008-01-01

    Quantitative solid sources are used widely in the field of radionuclide metrology. With the aim to improve the detection efficiency for electrons and x-rays, a comparative study between two source drying techniques has been undertaken at LNE-Laboratoire National Henri Becquerel (LNE-LNHB, France). In this paper, freeze-drying using commercial equipment is compared with a system of drying using hot jets of nitrogen developed at Institute for Reference Materials and Measurements (IRMM, Belgium). In order to characterize the influence of self-absorption, the detection efficiencies for 51 Cr sources have been measured by coincidence counting and photon spectrometry

  1. The effect of sublethal injury by heating, freezing, drying and gamma-radiation on the duration of the lag phase of Salmonella typhimurium

    International Nuclear Information System (INIS)

    Mackey, B.M.; Derrick, C.M.

    1982-01-01

    The duration of the lag phase of Salmonella typhimurium surviving heat, freezing, drying and gamma-radiation was used to indicate the time needed to repair sublethal injury. Following equivalent lethal treatments, heat and freeze-injured cells needed longer to repair than those injured by drying or gamma-radiation. Measurement of repair on membrane filters showed that in a heat-injured population having a lag time of 9 h, some individual cells needed up to 14 h to recover maximum tolerance to 3% NaCl. (author)

  2. Inhibition of the Growth of Plasmodium falciparum in Culture by Stearylamine-Phosphatidylcholine Liposomes

    Directory of Open Access Journals (Sweden)

    Gulam Mustafa Hasan

    2011-01-01

    Full Text Available We have examined the effect of stearylamine (SA in liposomes on the viability of Plasmodium falciparum in culture by studying the inhibition of incorporation of [3H]-hypoxanthine in the nucleic acid of parasites. Stearylamine in liposomes significantly inhibits the growth of the parasites depending on the phospholipids composition. The maximum inhibition was observed when SA was delivered through Soya phosphatidylcholine (SPC liposomes. The chain length of alkyl group and density of SA in liposomes play a significant role in inhibiting the growth of the parasites. Incorporation of either cholesterol or Distearylphosphatidylethanolamine−Methoxy-Polyethylene glycol-2000 (DSPE-mPEG-2000 in Soya phosphatidylcholine-stearylamine (SPC-SA liposomes improves the efficacy. Intraerythrocytic entry of intact SPC-SA liposomes into infected erythrocytes was visualized using fluorescent microscopy. No hemolysis was observed in uninfected erythrocytes, and slight hemolysis was noted in infected erythrocytes at high concentrations of SPC-SA liposomes. Overall, our data suggested SA in SPC-liposomes might have potential application in malaria chemotherapy.

  3. Presence of genetically modified soya in products on the market

    OpenAIRE

    Spanish Agency for Consumer Affairs, Food Safety and Nutrition

    2014-01-01

    In recent years, the number of events of Genetically Modified Organisms (GMO) authorised in the European Union to be used as food or feed has notably increased, particularly in the case of genetically modified soya. The number has grown from September 2008, when t here was only one authorisation, Mons anto Company's Roundup Ready® soya, to seven different events currently authorised: 40- 3-2 soya, MON89788 soya, MON87701 soya, A2704-12 soya, A5547-127 soya,...

  4. Safety assessment of freeze-dried powderedCassiae Semen: evaluation of chronic toxicity (26-week) in Sprague-Dawley rats.

    Science.gov (United States)

    Pei, Yanyu; Wei, Ruoyao; Sun, Jingjiang; Gao, Hong

    2017-01-01

    There is a lack of safety assessment data regarding the long-term consumption of Cassiae Semen (Leguminosae, the seeds of Cassia obtusifolia L. and Cassia tora L.). Thus, we evaluated the toxicity of freeze-dried powdered Cassiae Semen in male and female Sprague-Dawley rats. Rats were intragastrically administered freeze-dried powdered Cassiae Semen at a dose of 0.5, 2.2, or 10.0 g/kg body weight/day for 26 weeks; several variables were assessed after 13 and 26 weeks as well as after a 4-week recovery period. No mortality was observed in the treated animals, and body weight increased in a dose-dependent manner. The total bilirubin (TBIL) levels also displayed a dose-dependent relationship. In males, at 26 weeks, there were significant increases in relative kidney weights in the 2.2 and 10.0 g/kg groups compared with that in the negative control group (p Cassiae Semen in the 10.0 g/kg group were the kidneys.

  5. A comparative evaluation of extraction socket preservation with demineralized freeze-dried bone allograft alone and along with platelet-rich fibrin: A clinical and radiographic study

    Directory of Open Access Journals (Sweden)

    Dhaval J Thakkar

    2016-01-01

    Full Text Available Aims: To investigate clinically and radiographically, the bone fill in extraction sockets using demineralized freeze-dried bone allograft alone and along with platelet-rich fibrin (PRF. Materials and Methods: A randomized controlled clinical trial was carried out on 36 nonrestorable single-rooted teeth sites. Sites were randomized into demineralized freeze-dried bone allograft (DFDBA combined with PRF - test and DFDBA - control groups using a coin toss method. After the placement of graft material, collagen membrane was used to cover it. The clinical parameters recorded were ridge width and ridge height. All the parameters were recorded at baseline and at 90 and 180 days. Statistical Analysis Used: Independent t-test and paired t-test. Results: In both groups, there is significant reduction in loss of ridge width and ridge height from baseline to 90 days (P < 0.001, baseline to 180 days (P < 0.001, and 90-180 days (P < 0.001. However, when both the groups were compared the test group favored in the reduction of ridge width while there was no statistical difference in reduction of ridge height among at different intervals. Conclusions: Although DFDBA is considered as an ideal graft material, PRF can be used as an adjunctive with DFDBA for socket preservation.

  6. Encapsulation of antioxidant phenolic compounds extracted from spent coffee grounds by freeze-drying and spray-drying using different coating materials.

    Science.gov (United States)

    Ballesteros, Lina F; Ramirez, Monica J; Orrego, Carlos E; Teixeira, José A; Mussatto, Solange I

    2017-12-15

    Freeze-drying and spray-drying techniques were evaluated for encapsulation of phenolic compounds (PC) extracted from spent coffee grounds. Additionally, the use of maltodextrin, gum arabic and a mixture of these components (ratio 1:1) as wall material to retain the PC and preserve their antioxidant activity was also assessed. The contents of PC and flavonoids (FLA), as well as the antioxidant activity of the encapsulated samples were determined in order to verify the efficiency of each studied condition. Additional analyses for characterization of the samples were also performed. Both the technique and the coating material greatly influenced the encapsulation of antioxidant PC. The best results were achieved when PC were encapsulated by freeze-drying using maltodextrin as wall material. Under these conditions, the amount of PC and FLA retained in the encapsulated sample corresponded to 62% and 73%, respectively, and 73-86% of the antioxidant activity present in the original extract was preserved. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Impact of water activity, temperature, and physical state on the storage stability of Lactobacillus paracasei ssp. paracasei freeze-dried in a lactose matrix.

    Science.gov (United States)

    Higl, Bettina; Kurtmann, Lone; Carlsen, Charlotte U; Ratjen, Jennifer; Först, Petra; Skibsted, Leif H; Kulozik, Ulrich; Risbo, Jens

    2007-01-01

    The aim of this study was to determine whether the combined effect of water activity and temperature on inactivation rates of freeze-dried microorganisms in a lactose matrix could be explained in terms of the glass transition theory. The stabilized glass transition temperature, Tg, of the freeze-dried products was determined by differential scanning calorimetry at two different temperatures, T (20 and 37 degrees C), and different water activities (0.07-0.48). This information served as a basis for defining conditions of T and water activity, which led to storage of the bacteria in the glassy (T Tg) states. The rates of inactivation of the dry microorganisms subjected to different storage conditions were determined by plate counts and could be described by first-order kinetics. Rates were analyzed as a function of water activity, storage temperature, and the difference between Tg and T. Inactivation below Tg was low; however, Tg could not be regarded as an absolute threshold of bacteria stability during storage. When the cells were stored in the nonglassy state (T > Tg), inactivation proceeded faster, however, not as rapid as suggested by the temperature dependence of the viscosity above the glass transition temperature. Furthermore, the first-order rate constant, k, was dependent on the storage temperature per se rather than on the temperature difference between the glass transition temperature and the storage temperature (T - Tg).

  8. The Resistance to Freeze-Drying and to Storage Was Determined as the Cellular Ability to Recover Its Survival Rate and Acidification Activity

    Directory of Open Access Journals (Sweden)

    Ibourahema Coulibaly

    2010-01-01

    Full Text Available The protective effects of the fatty acid composition and membrane action of the acidification activity of two strains of Lactobacillus kept at 20∘C were studied. The addition of sorbitol, monosodium glutamate and glycerol during storage is causing the decline of acidification and increased concentrations of unsaturated fatty acids observed in both strains. The addition of sorbitol and monosodium glutamate does not alter the fatty acid composition, whatever the strain, but increases the resistance to freeze-drying of L. plantarum CWBI-B1419 and improves survival during storage. The addition of these preservatives and decreased activity of acidification improves the ratio unsaturated. These results indicate that the survival during storage and freeze-drying resistance are closely related to the composition of membrane fatty acids. This behaviour can be interpreted as an adaptation of L. plantarum B1419-CWBI supplemented by cryoprotectant additives such as sorbitol or monosodium glutamate sorbitol and monosodium glutamate as an additive. L. plantarum CWBI-B1419 presents a greater adaptation to culture conditions than L. paracasei ssp. paracasei LMG9192T.

  9. Freeze drying synthesis of Li3MnO4 cathode material for Li-ion batteries: A physico-electrochemical study

    International Nuclear Information System (INIS)

    Surace, Yuri; Simões, Mário; Karvonen, Lassi; Yoon, Songhak; Pokrant, Simone; Weidenkaff, Anke

    2015-01-01

    Highlights: • Facilitated synthesis of Li 3 MnO 4 with a smaller thermal budget via freeze drying. • Electrochemical activity enhanced by micro- and nanostructure modifications. • Capacity increase of 30% at 1st discharge versus standard synthesis process. - Abstract: Li 3 MnO 4 , a lithium rich phase containing manganese (V), is a promising cathode material for Li-ion batteries due to its very high theoretical capacity (698 A h kg −1 ). Li 3 MnO 4 was synthesized from freeze dried precursors at 398 K. Combined structural, morphological and chemical characterization by XRD, TGA, SEM, TEM and XPS revealed improvements in the micro- and nanostructure in comparison to the material synthesized by a standard solid state chemistry route. The average particle size decreased from 10 μm to 3.5 μm and the average crystallite size from close to 100 nm to around 30 nm. These modifications enhanced the capacity (23% at 10 A kg −1 and up to 31% at 50 A kg −1 with a maximum discharge capacity of 290 A h kg −1 ) and the rate capability

  10. An Insight into the Convenience and Efficiency of the Freeze-Drying Route to Construct 3D Graphene-Based Hybrids for Lithium-Ion Batteries

    International Nuclear Information System (INIS)

    Ding, Caihua; Zhao, Yongjie; Yan, Dong; Zhao, Yuzhen; Zhou, Heping; Li, Jingbo; Jin, Haibo

    2016-01-01

    Constructing hybrids of transition metal oxides with different kinds of carbon based materials has attracted a lot of attention recently. However, scalable synthesis of homogeneous hybrids with active controllable of microstructure remains great challenge. Here, we proposed a convenient and efficient strategy named freeze-drying process for scalable production of 3D NiO/graphene hybrids. With a controllable procedure, NiO microflowers and graphene layers could preserve uniform configuration from fully mixed solvent to final hybrids materials. The mechanical stability and electrical conductivity of NiO microflowers was increased by graphene. NiO microflowers as spacers intercalated into graphene layers and effectively prevented it from aggregation or restacking, leading to a high specific surface area in hybrids. The NiO/graphene exhibited enhanced cycle stability and rate performance when evaluated as an anode for lithium ion batteries. It rendered high specific capacities about 1000 mA h g −1 after 70 cycles, and 770 mA h g −1 after 100 cycles at 300 mA g −1 . Excellent electrochemical properties were probably ascribed to the synergistic effect of NiO microflowers and graphene layers, as a result of smart structure design by a freeze-drying route. This strategy with merits of rational construction and scalable production could establish new aspects for diverse hybrid towards industrialization.

  11. Effect of Hot-Water Blanching Pretreatment on Drying Characteristics and Product Qualities for the Novel Integrated Freeze-Drying of Apple Slices

    Directory of Open Access Journals (Sweden)

    Hai-ou Wang

    2018-01-01

    Full Text Available The effect of hot-water blanching (HWB on drying characteristics and product qualities of dried apple slices with the novel integrated freeze-drying (NIFD process was investigated by comparing with 3 different FD methods. Compared with the NIFD process without HWB pretreatment (VF-FD, the NIFD process with HWB pretreatment (HWB-VF-FD resulted in a significantly higher mass loss and more sufficient freezing in vacuum-frozen samples, significantly higher rehydration ratio (RR, higher shrinkage ratio (SR, smaller Vitamin C (VC content and lower hardness and better apparent shape in freeze-dried samples, and fewer change to the color of the dried or rehydrated samples (p<0.05. Compared with the conventional FD process with HWB pretreatment (HWB-PF-FD, HWB-VF-FD cost significantly less processing time and FD time and obtained significantly higher RR (p<0.05, almost the equivalent SR, VC content, and hardness, and similar appearance in dried samples. The microstructure of apple cell tissues was analyzed by transmission electron microscopy and scanning electron microscopy to interpret the above differences in drying characteristics and product qualities. The results suggested that the NIFD process of apple slices with HWB pretreatment was a promising alternative method to decrease drying time, achieve similar product quality, and simplify the process steps of the conventional FD technology.

  12. Freeze drying synthesis of Li{sub 3}MnO{sub 4} cathode material for Li-ion batteries: A physico-electrochemical study

    Energy Technology Data Exchange (ETDEWEB)

    Surace, Yuri; Simões, Mário; Karvonen, Lassi; Yoon, Songhak; Pokrant, Simone [Laboratory Materials for Energy Conversion, EMPA – Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf (Switzerland); Weidenkaff, Anke, E-mail: weidenkaff@imw.uni-stuttgart.de [Materials Chemistry, Institute for Materials Science, University of Stuttgart, Heisenbergstrasse 3, DE-70569 Stuttgart (Germany)

    2015-09-25

    Highlights: • Facilitated synthesis of Li{sub 3}MnO{sub 4} with a smaller thermal budget via freeze drying. • Electrochemical activity enhanced by micro- and nanostructure modifications. • Capacity increase of 30% at 1st discharge versus standard synthesis process. - Abstract: Li{sub 3}MnO{sub 4}, a lithium rich phase containing manganese (V), is a promising cathode material for Li-ion batteries due to its very high theoretical capacity (698 A h kg{sup −1}). Li{sub 3}MnO{sub 4} was synthesized from freeze dried precursors at 398 K. Combined structural, morphological and chemical characterization by XRD, TGA, SEM, TEM and XPS revealed improvements in the micro- and nanostructure in comparison to the material synthesized by a standard solid state chemistry route. The average particle size decreased from 10 μm to 3.5 μm and the average crystallite size from close to 100 nm to around 30 nm. These modifications enhanced the capacity (23% at 10 A kg{sup −1} and up to 31% at 50 A kg{sup −1} with a maximum discharge capacity of 290 A h kg{sup −1}) and the rate capability.

  13. Effect of ph on the stability of red beet extract (Beta vulgaris l. microcapsules produced by spray drying or freeze drying

    Directory of Open Access Journals (Sweden)

    Jéssica Loraine Duenha ANTIGO

    Full Text Available Abstract Red beets is rich in phenolic acids and has high antioxidant capacity, and can be used to produce a natural dye. This study evaluated the effect of pH (3 to 6 on the stability of red beet extract microcapsules, dried by freeze drying and spray drying and stored at room temperature. The microcapsules were produced using a combination of maltodextrin and xanthan gum as encapsulating agents and stored for 7 days. For all evaluated microcapsules, a degradation of betanin was observed, however, that degradation was independent of pH, with the exception of the sample with maltodextrin and dried by spray drying. The freeze dried products showed lower degradation constants and higher half-life (t1/2 when comparing with the spray dried samples. The microcapsules containing maltodextrin and xanthan gum, dried by spray drying, showed the highest change in the content of phenolic compounds after storage for 7 days. The color parameters showed a reduction for a*, and increase in b* and L*, for all samples during the storage time. In general, the microcapsules produced using maltodextrin and xanthan gum, and dried by freeze dryer, showed higher stability in terms of betanin content, phenolic compounds and color parameters during storage at different pHs.

  14. Solid state chemistry of proteins: I. glass transition behavior in freeze dried disaccharide formulations of human growth hormone (hGH).

    Science.gov (United States)

    Pikal, Michael J; Rigsbee, D R; Roy, M L

    2007-10-01

    Although freeze dried formulations are commonly characterized using differential scanning calorimetry (DSC), a protein-rich system behaves as a "strong glass", and the glass transition temperature, T(g), cannot be directly determined by DSC. A strong glass means a small heat capacity change at T(g), triangle upC(p), and a very broad glass transition region, or a large triangle upT(g). However, direct experimental evidence for a small triangle upC(p) and a large triangle upT(g) have been lacking. Here, we utilize extrapolation of thermal analysis data in protein:disaccharide mixtures to evaluate T(g), triangle upT(g), and triangle upC(p) for "pure" human growth hormone (hGH) from low to moderate residual water. We find that triangle upT(g) is indeed large and triangle upC(p) is very small. Also, the T(g) for pure hGH decreases from a value of about 136 degrees C when dry to around 25 degrees C at 12% water. This glass transition is not the onset of mobility within the protein molecule but rather signals onset of whole molecule rotation and translation. We also observe complex pre-T(g) thermal events in the DSC data, which are interpreted as consequences of relaxation events, largely due to the disaccharide, and are characteristic of freeze dried systems having a broad distribution of relaxing substates. (c) 2007 Wiley-Liss, Inc.

  15. Mannitol/l-Arginine-Based Formulation Systems for Freeze Drying of Protein Pharmaceuticals: Effect of the l-Arginine Counter Ion and Formulation Composition on the Formulation Properties and the Physical State of Mannitol.

    Science.gov (United States)

    Stärtzel, Peter; Gieseler, Henning; Gieseler, Margit; Abdul-Fattah, Ahmad M; Adler, Michael; Mahler, Hanns-Christian; Goldbach, Pierre

    2016-10-01

    Previous studies have shown that protein storage stability in freeze-dried l-arginine-based systems improved in the presence of chloride ions. However, chloride ions reduced the glass transition temperature of the freeze concentrate (Tg') and made freeze drying more challenging. In this study, l-arginine was freeze dried with mannitol to obtain partially crystalline solids that can be freeze dried in a fast process and result in elegant cakes. We characterized the effect of different l-arginine counter ions on physicochemical properties of mannitol compared with mannitol/sucrose systems. Thermal properties of formulations with different compositions were correlated to thermal history during freeze drying and to physicochemical properties (cake appearance, residual moisture, reconstitution time, crystallinity). Partially crystalline solids were obtained even at the highest l-arginine level (mannitol:l-arginine of 2:1) used in this study. All l-arginine-containing formulations yielded elegant cakes. Only cakes containing l-arginine chloride and succinate showed a surface "crust" formed by phase separation. X-ray powder diffraction showed that inhibition of mannitol crystallization was stronger for l-arginine compared with sucrose and varied with the type of l-arginine counter ion. The counter ion affected mannitol polymorphism and higher levels of mannitol hemi-hydrate were obtained at high levels of l-arginine chloride. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  16. Freeze drying of L-arginine/sucrose-based protein formulations, part I: influence of formulation and arginine counter ion on the critical formulation temperature, product performance and protein stability.

    Science.gov (United States)

    Stärtzel, Peter; Gieseler, Henning; Gieseler, Margit; Abdul-Fattah, Ahmad M; Adler, Michael; Mahler, Hanns-Christian; Goldbach, Pierre

    2015-07-01

    The objective of this study was to investigate product performance of freeze dried l-arginine/sucrose-based formulations under variation of excipient weight ratios, l-arginine counter ions and formulation pH as a matrix to stabilize a therapeutic monoclonal antibody (MAb) during freeze drying and shelf life. Protein and placebo formulations were lyophilized at aggressive primary drying conditions and key attributes of the freeze dried solids were correlated to their thermal properties and critical formulation temperature. Stability (physical) during processing and long-term storage of the MAb in different formulations was assessed by SE-HPLC. Thermal properties of the mixtures were greatly affected by the type of l-arginine counter ion. High glass transition temperatures were achieved by adding multivalent acids, whereas the temperature values significantly decreased in the presence of chloride ions. All mixtures were stable during freeze drying, but storage stability varied for the different preparations and counter ions. For l-arginine-based formulations, the protein was most stable in the presence of chloride ion, showing no obvious correlation to estimated global mobility of the glass. Besides drying behavior and thermal properties of the freeze dried solids, the counter ion of l-arginine must be considered relevant for protein shelf life stability. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  17. Extended release promethazine HCl using acrylic polymers by freeze-drying and spray-drying techniques: formulation considerations

    Directory of Open Access Journals (Sweden)

    Ruchi Tiwari

    2009-12-01

    Full Text Available The present study investigated a novel extended release system of promethazine hydrochloride (PHC with acrylic polymers Eudragit RL100 and Eudragit S100 in different weight ratios (1:1 and 1: 5, and in combination (0.5+1.5, using freeze-drying and spray-drying techniques. Solid dispersions were characterized by Fourier-transformed infrared spectroscopy (FT-IR, differential scanning calorimetry (DSC, Powder X-ray diffractometry (PXRD, Nuclear magnetic resonance (NMR, Scanning electron microscopy (SEM, as well as solubility and in vitro dissolution studies in 0.1 N HCl (pH 1.2, double-distilled water and phosphate buffer (pH 7.4. Adsorption tests from drug solution to solid polymers were also performed. A selected solid dispersion system was developed into capsule dosage form and evaluated for in vitro dissolution studies. The progressive disappearance of drug peaks in thermotropic profiles of spray-dried dispersions were related to increasing amount of polymers, while SEM studies suggested homogenous dispersion of drug in polymer. Eudragit RL100 had a greater adsorptive capacity than Eudragit S100, and thus its combination in (0.5+1.5 for S100 and RL 100 exhibited a higher dissolution rate with 97.14% drug release for twelve hours. Among different formulations, capsules prepared by combination of acrylic polymers using spray-drying (1:0.5 + 1.5 displayed extended release of drug for twelve hours with 96.87% release followed by zero order kinetics (r²= 0.9986.O presente trabalho compreendeu estudo de um novo sistema de liberação prolongada de cloridrato de prometazina (PHC com polímeros acrílicos Eudragit RL100 e Eudragit S100 em diferentes proporções em massa (1:1 e 1:5 e em combinação (0,5+1,5, utilizando técnicas de liofilização e de secagem por aspersão As dispersões sólidas foram caracterizadas por espectrofotometria no infravermelho por transformada de Fourier (FT-IR, calorimetria diferencial de varredura (DSC, difratometria

  18. Danube Soya – Improving European GM-free soya supply for food and feed

    Directory of Open Access Journals (Sweden)

    Krön Matthias

    2015-09-01

    Full Text Available The Danube Soya Association is an international, voluntary, non-profit, non-governmental association promoting sustainable and GMO**-free soya production along the Danube River Basin – from Switzerland to the Black Sea. Founded in 2012 the association counts today more than 200 members from the whole value chain and civil society in 16 European countries. The members share the vision of a protein transition towards more European and more sustainable protein sources for food and feed. The Danube Area is an area of large potential agricultural surpluses and Danube Soya promotes the idea of using these surpluses to replace a part of the imported soya. The goals of the association are to increase value-added in the rural economies of Central Eastern Europe, promote European cooperation as well as a production of constant and sustainable local soya sources. The Danube Soya Association runs a certification scheme that reaches from soya seeds all the way to final products, which can be labelled with the consumer label “Fed with Danube Soya” (for animal products and “Danube Soya” (for soya food products. Together with its partners, the Danube Soya Association implements and supports dissemination and research projects on different topics.

  19. Synthesis of epoxidised soya bean oil acrylate

    International Nuclear Information System (INIS)

    Hussin bin Mohd Nor; Mohamad Hilmi bin Mahmood; Dahlan bin Haji Mohd.

    1988-10-01

    An epoxy acrylate was synthesized from Asahi's epoxy resin AER 331 which is an epoxidised soya bean oil (ESBO). Triethylamine (TEA) and Hydroquinone (HQ) were used as catalyst and inhibitor respectively. Observations of the experiment are described. (author)

  20. Characterization of biomasses, concentrates, and permeates of dried powder of Kombucha fermentation of spinach (Amaranthus sp.) and broccoli (Brassica oleracea) with membrane microfiltration and freeze drying techniques for natural sources of folic acid

    Science.gov (United States)

    Nugraha, Tutun; Susilowati, Agustine; Aspiyanto, Lotulung, Puspa Dewi; Maryati, Yati

    2017-11-01

    Fermentation of spinach (Amaranthus sp) and Broccoli (Brassica oleracea) using Kombucha Culture has been shown to produce biomass that has the potential to become natural sources of folic acid. To produce the materials, following the fermentation, the biomass was filtered using membrane microfiltration (0.15 µm) at a pressure of 40 psia, at room temperature, yielding the concentrate and the permeate fractions. Following this step, freeze drying process was done on the biomass feeds, as well as on the concentrate and permeate fractions. For the freeze drying stage, the samples were frozen, and the condenser was kept at -50°C for 40 hours, while the pressure in the chamber was set at 200 Pa. Freeze drying results showed that the final products, have differences in compositions, as well as differences in the dominat monomers of folates. After water content was driven out, freeze drying increased the concentrations of folic acid in the dried products, and was found to be the highest in the concentrate fractions. Freeze drying has been shown to be capable of protecting the folates from heat and oxidative damages that typicaly occur with other types of drying. The final freeze dried concentrates of fermentation of spinach and broccoli were found to contain folic acid at 2531.88 µg/mL and 1626.94 µg/mL, total solids at 87.23% and 88.65 %, total sugar at 22.66 µg/mL and 25.13 µg/mL, total reducing sugar at 34.46 mg/mL and 15.22 mg/mL, as well as disolved protein concentrations at 0.93 mg/mL and 1.45 mg/mL. Liquid Chromatography Mass Spectometry (LC-MS) identification of the folates in the freeze dried concentrates of fermented spinach and broccoli was done using folic acid and glutamic acid standard solutions as the reference materials. The results showed the presence of folic acid and showed that the dominant monomers of molecules of folates with molecular weights of 441.44 Da. and 441.54 Da. for spinach and broccoli respectively. Moreover, the monomers of glutamic

  1. Suitability of near-infrared methods for the determination of moisture in a freeze-dried injection product containing different amounts of the active ingredient.

    Science.gov (United States)

    Last, I R; Prebble, K A

    1993-01-01

    A near-infrared reflectance (NIR) method for determination of moisture in an experimental freeze-dried injection product was developed and validated. NIR spectra were collected through the bases of unopened product vials using a horizontal instrument accessory, before generating primary reference data on the same individual vials by Karl-Fischer titration. Data were collected for product containing different concentrations of the active ingredient in the same matrix. NIR calibrations were developed with second derivative spectral data using regression facilities within the NIR software, and validated using independent test sets. An assessment is given of the applicability of moisture calibrations developed on product at one active ingredient level to the prediction of moisture contents in the product containing a different concentration of active ingredient.

  2. Crystal phase evolution of TiO2 nanoparticles with reaction time in acidic solutions studied via freeze-drying method

    International Nuclear Information System (INIS)

    Shin, Hyunho; Jung, Hyun Suk; Hong, Kug Sun; Lee, Jung-Kun

    2005-01-01

    The crystal phase evolution of TiO 2 nanoparticles, during hydrolysis and condensation of titanium tetraisopropoxide, was quenched at various reaction times by a freeze-drying method, followed by various characterizations. Three types of solutions with different acid input times were studied: (1) addition in infinite time (no addition) (2) addition at 24h after the hydrolysis/condensation reaction started, and (3) addition from the beginning of the reaction. The acid-free solution yielded amorphous TiO 2 , which transformed to anatase very slowly. The acid input in 24h resulted in a fast transformation of amorphous to a metastable anatase having a highly distorted atomic arrangement: thereby its transformation to a more stable phase, rutile, was suitable. The acid addition from the beginning of the reaction yielded the formation of a relatively stable anatase from the hydrolysis seed, thereby the subsequent transformation to rutile was sluggish

  3. The pharmaceutical applications of a biopolymer isolated from Trigonella foenum-graecum seeds: Focus on the freeze-dried matrix forming capacity

    Directory of Open Access Journals (Sweden)

    Sonia Iurian

    2017-12-01

    The FSM dispersions revealed shear thinning flow type. Based on colloidal dispersions' rheological properties, five FSM concentrations were taken forward to the lyophilization step. Completely dry and elegant tablets were obtained. Texture analysis indicated highly porous structures, confirmed by SEM analysis, which explain the fast disintegration properties. All the prepared tablets disintegrated in less than 47 s. The disintegration process was prolonged by the increase in FSM content, due to the high viscosity the polymer creates in aqueous media. FSM tablets presented longer disintegration times, as compared to gelatin tablets, but also higher crushing strength. Considering the fast disintegration and the high crushing strength, FSM is a good candidate as matrix forming agent for fast disintegrating dosage forms or other freeze-dried preparations.

  4. Effects of freeze-dried strawberry supplementation on metabolic biomarkers of atherosclerosis in subjects with type 2 diabetes: a randomized double-blind controlled trial.

    Science.gov (United States)

    Moazen, Sara; Amani, Reza; Homayouni Rad, Aziz; Shahbazian, Hajieh; Ahmadi, Kambiz; Taha Jalali, Mohammad

    2013-01-01

    To our knowledge there has been no study investigating the impact of freeze-dried strawberry (FDS) supplementation on metabolic biomarkers of atherosclerosis in subjects with type 2 diabetes (T2D). This study was carried out to determine the effects of FDS supplementation on glycemic control, biomarkers of oxidative stress, inflammation and serum total antioxidant status in subjects with T2D compared to matched control subjects. Thirty-six subjects with T2D (23 females; mean body mass index 27.90 ± 3.7; mean age 51.57 ± 10 years) were randomly divided into two groups. The treatment group consumed 2 cups of FDS beverage (50 g of FDS is equivalent to 500 g of fresh strawberries) or macronutrient matched placebo powder with strawberry flavor daily for 6 weeks in a randomized double-blind controlled trial. Anthropometric measurements, dietary intakes, hemoglobin (Hb)A1c, antioxidant status, C-reactive protein and malondialdehyde (MDA) levels were assessed at baseline and 6 weeks post-intervention. FDS supplementation significantly decreased C-reactive protein levels as a biomarker of inflammation (2.5 vs. 2.04 mg/l, p peroxidation in the form of MDA (3.36 vs. 2.7 nmol/ml, p peroxidation and inflammatory response in patients with T2D. Supplementation with freeze-dried berry products, as natural sources of antioxidants with low glycemic index, could be considered as an adjunctive therapy in ameliorating metabolic complications of T2D.

  5. Influence of Freeze-Drying and Oven-Drying Post Blanching on the Nutrient Composition of the Edible Insect Ruspolia differens

    Directory of Open Access Journals (Sweden)

    Forkwa Tengweh Fombong

    2017-09-01

    Full Text Available The longhorn grasshopper, Ruspolia differens (Serville, plays an important role as a food source across Sub-Saharan Africa, where it is consumed as a delicacy in both rural and urban areas. The effect of two drying methods (freeze-drying and oven-drying, employed after blanching, on the proximate, fatty acid and mineral composition of the two most common morphs was determined. Ruspolia differens grasshoppers were harvested in Uganda and Kenya from wild swarms during the rainy periods of November–December 2016. Based on cuticular coloration, we identified three morphs, green, brown and purple, which occurred at a ratio of 65:33:2, respectively. Results indicated that these insects have a high lipid content of 36%, as well as significant protein levels ranging between 33% and 46% dry matter. Oleic acid (44% and palmitic acid (28% were the two most abundant fatty acids; while the presence of arachidonic acid (0.6% and docosahexaenoic acid (0.21% suggests that Ruspolia differens is also a source of polyunsaturated fatty acids. The observed amino acid profile showed similar trends in all morphs, and all essential amino acids were present. Calcium (896–1035 mg/100 g, potassium (779–816 mg/100 g and phosphorus (652–685 mg/100 g were quite high among the minerals. The presence of the trace elements iron (217–220 mg/100 g, zinc (14.2–14.6 mg/100 g, manganese (7.4–8.3 mg/100 g and copper (1.66 mg/100 g suggests that inclusion of these grasshoppers in human diets may aid in combatting micronutrient deficiencies. Oven-drying Ruspolia differens delivered the same nutritional quality as freeze-drying. Hence, both drying approaches can be adequately used to formulate insect-based food products without noticeable nutritional changes.

  6. The effect of freeze-dried antibody concentrations on its stability in the presence of trehalose and hydroxypropyl-β-cyclodextrin: a Box-Behnken statistical design.

    Science.gov (United States)

    Faghihi, Homa; Khalili, Fatemeh; Amini, Mohsen; Vatanara, Alireza

    2017-09-01

    The present study aimed at preparation and optimization of stable freeze-dried immunoglobulin G (IgG) applying proper amount of antibody with efficient combination of trehalose and hydroxypropyl-β-cyclodextrin (HPβCD). Response surface methodology was employed through a three-factor, three-level Box-Behnken design. Amounts of IgG (X 1 ), trehalose (X 2 ) and HPβCD (X 3 ) were independent variables. Aggregation following process (Y 1 ), after one month at 45 °C (Y 2 ), upon two month at 45 °C (Y 3 ) and beta-sheet content of IgG (Y 4 ) were determined as dependent variables. Results were fitted to quadratic models (except for beta-sheet content), describing the inherent relationship between main factors. Optimized formulation composed of 55.85 mg IgG, 52.51 mg trehalose and 16.01 mg HPβCD was prepared. The calculated responses of the optimized formulation were as follows: Y 1  = 0.19%, Y 2  = 0.78%, Y 3  = 1.88% and Y 4  = 68.60%, respectively. The thermal analysis confirmed the amorphous nature of optimum formulation and the integrity of IgG was shown to be favorably preserved. Validation of the optimization study demonstrated high degree of prognostic ability. The DOE study successfully predicted the optimum values of antibody as well as stabilizers for desirable process and storage stabilization of freeze-dried IgG.

  7. Freeze-drying synthesis of Li3V2(PO4)3/C cathode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Qiao, Y.Q.; Wang, X.L.; Mai, Y.J.; Xia, X.H.; Zhang, J.; Gu, C.D.; Tu, J.P.

    2012-01-01

    Highlights: ► Li 3 V 2 (PO 4 ) 3 /C was synthesized by freeze-drying method. ► A specific capacity of 105.6 mAh g −1 can be obtained at 14.8 C. ► 93.3 mAh g −1 can be delivered at a higher current density of 29.6 C. ► The Li 3 V 2 (PO 4 ) 3 /C electrode shows a good cycling performance. - Abstract: Li 3 V 2 (PO 4 ) 3 /C cathode material was synthesized by using a freeze-drying method followed by carbon-thermal reduction. This as-prepared material has a uniform particle size distribution and a well carbon coating on the surface of Li 3 V 2 (PO 4 ) 3 particles. The Li 3 V 2 (PO 4 ) 3 /C exhibits good electrochemical performance and cycling stability. Between 3.0 and 4.3 V, the composite delivered a reversible capacity of 125.2 mAh g −1 at a charge–discharge rate of 1.48 C (1 C = 133 mA g −1 ) and without obviously capacity fading after 100 cycles. Even at 14.8 C and 29.6 C rates, it can still deliver discharge capacities of 105.6 mAh g −1 and 93.3 mAh g −1 , and the discharge capacities of 84.5 and 60.5 mAh g −1 are sustained after 500 cycles, respectively.

  8. Freeze-drying as an alternative method of human sclera preservation Liofilização como alternativa à preservação de esclera humana

    Directory of Open Access Journals (Sweden)

    Ana Carolina de Arantes Frota

    2008-04-01

    Full Text Available PURPOSE: To compare the effect of preserving sclera samples in either 95% ethanol or freeze-dried. METHODS: Ninety-six samples of human sclera were studied. Half of them were freeze-dried and half preserved in 95% ethanol. Preservation periods of 18, 45, 90 or 174 days were studied. Automated immunostaining was carried out in the Ventana BenchMarkR LT platform using collagen 1 and fibronectin antibodies. Histological staining was also performed with hematoxilin-eosin and Masson trichrome. Samples were classified according to the degree of collagen fiber parallelism (0-2, intensity of Masson staining (0-2, and the expression of both antibodies (0-3. Friedman and Wilcoxon tests were applied to compare preservation methods and p-values below 0.05 were considered to ensure statistical significance. RESULTS: Relevant results were found in three situations: (i Friedman's test showed better collagen fiber integrity in the freeze-dried group rehydrated after 174-days as compared to the 90-day group; (ii Wilcoxon's test showed better collagen fiber integrity in the freeze-dried group after 18 and 174 days as compared to the ethanol group; (iii the freeze-dried group disclosed higher immunohistochemical expression for COL-1 antibody in the sclera samples rehydrated after 45, 90 and 174 days as compared to the ones rehydrated after 18 days. CONCLUSION: Histological and immunohistochemical analysis showed freeze-drying to be a superior method for sclera preservation as compared to 95% ethanol. This technique provides an easy method to manipulate tissue, with longer shelf life, and storage at room temperature.OBJETIVO: Comparar dois métodos de preservação de esclera humana, liofilização e álcool 95%, em diferentes períodos de tempo. MÉTODOS: Foram avaliados 96 fragmentos de seis escleras humanas. Metade das amostras foi submetida ao processo de liofilização e metade conservada em álcool 95%. Dois fragmentos de cada grupo foram avaliados pelas

  9. Pulmonary delivery of an inulin-stabilized influenza subunit vaccine prepared by spray-freeze drying induces systemic, mucosal humoral as well as cell-mediated immune responses in BALB/c mice

    NARCIS (Netherlands)

    Amorij, J-P.; Saluja, V.; Petersen, A.H.; Hinrichs, W.L.J.; Huckriede, A.; Frijlink, H.W.

    2007-01-01

    In this study pulmonary vaccination with a new influenza subunit vaccine powder was evaluated. Vaccine powder was produced by spray-freeze drying (SFD) using the oligosaccharide inulin as stabilizer. Immune responses after pulmonary vaccination of BALB/c mice with vaccine powder were determined and

  10. A comparison of freeze-drying and oven-drying preparation methods for bulk and compound-specific carbon stable isotope analyses: examples using the benthic macroinvertebrates Stenopsyche marmorata and Epeorus latifolium.

    Science.gov (United States)

    Akamatsu, Fumikazu; Suzuki, Yaeko; Kato, Yoshikazu; Yoshimizu, Chikage; Tayasu, Ichiro

    2016-01-15

    Carbon stable isotope analysis of bulk samples and fatty acids is an established method for tracing carbon flow pathways and reconstructing trophic interactions, but there is no consensus on which sample drying method should be used for sample preparation. The aim of this study was to determine if freeze-drying and oven-drying treatments used to prepare samples of the benthic macroinvertebrates Stenopsyche marmorata and Epeorus latifolium for bulk and fatty-acid-specific carbon stable isotope analysis yield different isotopic ratio values. Five individuals each from two species were split in half; one half was freeze-dried and the other half was oven-dried. The samples were ground and the δ(13)C values of the bulk samples and eight fatty acids were measured following combustion using an isotope ratio mass spectrometer coupled to an elemental analyzer or gas chromatography system. The mean difference in the bulk and fatty acid δ(13)C values between freeze-dried and oven-dried samples was small (≤0.1‰ in both cases), although relatively large variations were observed in individual fatty-acid-specific δ(13)C values (maximum of ≤0.9 ‰). There were no significant differences in either bulk sample or fatty-acid-specific δ(13)C values between freeze-dried or oven-dried samples of the same species. Freeze-drying and oven-drying are equally acceptable methods for preparing freshly caught S. marmorata and E. latifolium samples for bulk and fatty-acid-specific carbon stable isotope analyses. Copyright © 2015 John Wiley & Sons, Ltd.

  11. Bacteriological Contamination of Soya Bean Flour Sold in Makurdi ...

    African Journals Online (AJOL)

    Soya bean (Glycine max) is a leguminous crop that is used as a staple food worldwide. The raw harvest is processed into various food forms like soya bean flour and processing methods increase the chances of bacterial contamination. This research work assessed the bacteria contamination of soya bean flour sold in and ...

  12. Quality, safety, biofunctionality and fermentation control in soya

    NARCIS (Netherlands)

    Nout, M.J.R.

    2015-01-01

    Fermented soya foods play an important role in the diet and health of a large part of the world population. We will discuss the manufacture and properties of: soya sauce; semi-solid pastes such as miso, doujiang and doenjang; and solid fermented soya foods such as natto, kinema, tempe, sufu and

  13. Effects of fermented soya bean on digestion, absorption and diarrhoea

    NARCIS (Netherlands)

    Kiers, J.L.

    2001-01-01

    For many centuries Asian people have consumed soya beans in various forms of traditional fermented soya bean foods. Major desirable aspects of fermented soya bean foods are their attractive flavour and texture, certain nutritional properties, and possible health promoting effects. This

  14. The influence of freeze drying and ϒ-irradiation in pre-clinical studies of flurbiprofen polymeric nanoparticles for ocular delivery using D-(+-trehalose and polyethylene glycol

    Directory of Open Access Journals (Sweden)

    Ramos Yacasi GR

    2016-08-01

    Full Text Available Gladys Rosario Ramos Yacasi, María Luisa García López, Marta Espina García, Alexander Parra Coca, Ana Cristina Calpena Campmany Department of Pharmacy and Pharmaceutical Technology and Physical Chemistry, University of Barcelona, Barcelona, Spain Abstract: This study investigated the suspension of poly(ε-caprolactone nanoparticles as an ocular delivery system for flurbiprofen (FB-PεCL-NPs in order to overcome the associated problems, such as stability, sterility, tolerance, and efficacy, with two different FB-PεCL-NP formulations. The formulations were stabilized with poloxamer 188 (1.66% and 3.5% and submitted individually for freeze-drying and γ-irradiation with polyethylene glycol 3350 (PEG3350 and d-(+-trehalose (TRE. Both formulations satisfied criteria according to all physicochemical parameters required for ocular pharmaceuticals. The FB-PεCL-NP formulations showed non-Newtonian behavior and sustained drug release. Ex vivo permeation analysis using isolated ocular pig tissues suggested that the presence of PEG3350 results in a reduction of FB transcorneal permeation. Moreover, TRE improved the penetration of FB across the cornea, especially after γ-irradiation. In addition, both formulations did not show a significant affinity in increasing FB transscleral permeation. Both formulations were classified as nonirritating, safe products for ophthalmic administration according to hen’s egg test-chorioallantoic membrane and Draize eye test. Furthermore, an in vivo anti-inflammatory efficacy test showed that irradiated FB-PεCL-NPs prepared with PEG3350 (IR-NPsPEG have longer anti-inflammatory effects than those presented with irradiated FB-PεCL-NPs prepared with TRE (IR-NPsTRE. IR-NPsPEG showed a suitable physical stability after an aqueous reconstitution over .30 days. This study concludes that both formulations meet the Goldman’s criteria and demonstrate how irradiated nanoparticles, with innovative permeation characteristics

  15. Polifenoles y Actividad Antioxidante del Fruto Liofilizado de Palma Naidi (Açai Colombiano (Euterpe oleracea Mart Polyphenols and Antioxidant Activity of the Freeze-Dried Palm Naidi (Colombian Açai (Euterpe oleracea Mart

    Directory of Open Access Journals (Sweden)

    Benjamín Alberto Rojano

    2011-12-01

    Full Text Available Euterpe oleracea es una palmera indígena autóctona de América del Sur. El fruto conocido como açaí en Brasil y palma naidi en Colombia, es de gran valor económico para los pueblos nativos. Para los análisis se usó una pulpa liofilizada, proveniente del Pacifico colombiano. Entre los muchos hallazgos, se presenta un alto porcentaje de minerales (6,94%, específicamente sodio, hierro y potasio. La palma naidi es rica en compuestos polifenólicos, tipo antocianinas (268,5 mg Cianidin-3-Glucosido/ 100 g de liofilizado donde el 95% de las antocianinas corresponden al Cianidin-3-Glucosido (255,1 mg/ 100 g de liofilizado y de otros compuestos fenólicos como los ácidos fenólicos: ferúlico (10,27 mg/100 g de liofilizado, caféico (7,06 mg/100 g de liofilizado, p-coumárico (2,81 mg/100 g de liofilizado y menor cantidad clorogénico 0,30 mg/100 g de liofilizado. Los polifenoles contribuyen a la capacidad antioxidante del naidi; medida por las técnicas ABTS, DPPH y FRAP y específicamente un valor ORAC (Hidrofílico (Oxygen Radical Absorbance Capacity de 98142,0 Micromol Tx/100 g de liofilizado; además un valor ORAC Lipofílico de 3194,1 Micromol Tx/ 100 g de liofilizado. Un valor ORAC total igual a 101336,1 Micromol Tx/ 100 g de liofilizado.Euterpe oleracea Mart is a native palm tree native of South America. The fruit known as açaí in Brazil and naidi palm in Colombia and is of great economic value to the native peoples. For the analysis was used freeze-dried pulp, from the Colombian Pacific. This fruit has a high percentage of minerals (6.94%, specifically sodium, potassium and iron. Naidi palm is rich in polyphenolic compounds, especially anthocyanins (268.5 mg cyanidin-3-glucoside per 100 g of freeze dried and phenolic acid as ferulic (10.27 mg/100 g of freeze dried , caffeic (7.06 mg/100 g of freeze dried, p-Coumaric (2.81 mg/100 g of freeze dried and fewer chlorogenic (0.30 mg/100 g of freeze dried; which provides high antioxidant

  16. ELISA for Detection of Soya Proteins in Meat Products

    Directory of Open Access Journals (Sweden)

    Eva Renčová

    2009-01-01

    Full Text Available Indirect competitive ELISA method for the detection of soya proteins in meat products was developed. The detection limit of the method is 0.5% of the weight of added soya protein. A total of 131 meat product samples such as salamis or sausages from the Czech Republic market were investigated for the presence of soya proteins. Soya proteins were detected in 84% of the investigated samples without any declaration on the package of the product. The use of vegetable additives, namely soya in meat products in the market of the Czech Republic is very frequent and the restriction of its usage by legislation relates only to some kinds of durable products and ham (Act 264/2003 Coll.. The need for sensitive inspecting methods for soya protein detection is not only associated with the economic aspect (adulteration, but mainly with consumer health protection in case of allergy to soya proteins.

  17. Freeze-Dried Platelet-Rich Plasma Accelerates Bone Union with Adequate Rigidity in Posterolateral Lumbar Fusion Surgery Model in Rats

    Science.gov (United States)

    Shiga, Yasuhiro; Orita, Sumihisa; Kubota, Go; Kamoda, Hiroto; Yamashita, Masaomi; Matsuura, Yusuke; Yamauchi, Kazuyo; Eguchi, Yawara; Suzuki, Miyako; Inage, Kazuhide; Sainoh, Takeshi; Sato, Jun; Fujimoto, Kazuki; Abe, Koki; Kanamoto, Hirohito; Inoue, Masahiro; Kinoshita, Hideyuki; Aoki, Yasuchika; Toyone, Tomoaki; Furuya, Takeo; Koda, Masao; Takahashi, Kazuhisa; Ohtori, Seiji

    2016-11-01

    Fresh platelet-rich plasma (PRP) accelerates bone union in rat model. However, fresh PRP has a short half-life. We suggested freeze-dried PRP (FD-PRP) prepared in advance and investigated its efficacy in vivo. Spinal posterolateral fusion was performed on 8-week-old male Sprague-Dawley rats divided into six groups based on the graft materials (n = 10 per group): sham control, artificial bone (A hydroxyapatite-collagen composite) -alone, autologous bone, artificial bone + fresh-PRP, artificial bone + FD-PRP preserved 8 weeks, and artificial bone + human recombinant bone morphogenetic protein 2 (BMP) as a positive control. At 4 and 8 weeks after the surgery, we investigated their bone union-related characteristics including amount of bone formation, histological characteristics of trabecular bone at remodeling site, and biomechanical strength on 3-point bending. Comparable radiological bone union was confirmed at 4 weeks after surgery in 80% of the FD-PRP groups, which was earlier than in other groups (p < 0.05). Histologically, the trabecular bone had thinner and more branches in the FD-PRP. Moreover, the biomechanical strength was comparable to that of autologous bone. FD-PRP accelerated bone union at a rate comparable to that of fresh PRP and BMP by remodeling the bone with thinner, more tangled, and rigid trabecular bone.

  18. Iodine and freeze-drying enhanced high-resolution MicroCT imaging for reconstructing 3D intraneural topography of human peripheral nerve fascicles.

    Science.gov (United States)

    Yan, Liwei; Guo, Yongze; Qi, Jian; Zhu, Qingtang; Gu, Liqiang; Zheng, Canbin; Lin, Tao; Lu, Yutong; Zeng, Zitao; Yu, Sha; Zhu, Shuang; Zhou, Xiang; Zhang, Xi; Du, Yunfei; Yao, Zhi; Lu, Yao; Liu, Xiaolin

    2017-08-01

    The precise annotation and accurate identification of the topography of fascicles to the end organs are prerequisites for studying human peripheral nerves. In this study, we present a feasible imaging method that acquires 3D high-resolution (HR) topography of peripheral nerve fascicles using an iodine and freeze-drying (IFD) micro-computed tomography (microCT) method to greatly increase the contrast of fascicle images. The enhanced microCT imaging method can facilitate the reconstruction of high-contrast HR fascicle images, fascicle segmentation and extraction, feature analysis, and the tracing of fascicle topography to end organs, which define fascicle functions. The complex intraneural aggregation and distribution of fascicles is typically assessed using histological techniques or MR imaging to acquire coarse axial three-dimensional (3D) maps. However, the disadvantages of histological techniques (static, axial manual registration, and data instability) and MR imaging (low-resolution) limit these applications in reconstructing the topography of nerve fascicles. Thus, enhanced microCT is a new technique for acquiring 3D intraneural topography of the human peripheral nerve fascicles both to improve our understanding of neurobiological principles and to guide accurate repair in the clinic. Additionally, 3D microstructure data can be used as a biofabrication model, which in turn can be used to fabricate scaffolds to repair long nerve gaps. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Comparison of blueberry powder produced via foam-mat freeze-drying versus spray-drying: evaluation of foam and powder properties.

    Science.gov (United States)

    Darniadi, Sandi; Ho, Peter; Murray, Brent S

    2018-03-01

    Blueberry juice powder was developed via foam-mat freeze-drying (FMFD) and spray-drying (SD) via addition of maltodextrin (MD) and whey protein isolate (WPI) at weight ratios of MD/WPI = 0.4 to 3.2 (with a fixed solids content of 5 wt% for FMFD and 10 wt% for SD). Feed rates of 180 and 360 mL h -1 were tested in SD. The objective was to evaluate the effect of the drying methods and carrier agents on the physical properties of the corresponding blueberry powders and reconstituted products. Ratios of MD/WPI = 0.4, 1.0 and 1.6 produced highly stable foams most suitable for FMFD. FMFD gave high yields and low bulk density powders with flake-like particles of large size that were also dark purple with high red values. SD gave low powder recoveries. The powders had higher bulk density and faster rehydration times, consisting of smooth, spherical and smaller particles than in FMFD powders. The SD powders were bright purple but less red than FMFD powders. Solubility was greater than 95% for both FMFD and SD powders. The FMFD method is a feasible method of producing blueberry juice powder and gives products retaining more characteristics of the original juice than SD. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  20. Global Sensitivity Analysis as Good Modelling Practices tool for the identification of the most influential process parameters of the primary drying step during freeze-drying.

    Science.gov (United States)

    Van Bockstal, Pieter-Jan; Mortier, Séverine Thérèse F C; Corver, Jos; Nopens, Ingmar; Gernaey, Krist V; De Beer, Thomas

    2018-02-01

    Pharmaceutical batch freeze-drying is commonly used to improve the stability of biological therapeutics. The primary drying step is regulated by the dynamic settings of the adaptable process variables, shelf temperature T s and chamber pressure P c . Mechanistic modelling of the primary drying step leads to the optimal dynamic combination of these adaptable process variables in function of time. According to Good Modelling Practices, a Global Sensitivity Analysis (GSA) is essential for appropriate model building. In this study, both a regression-based and variance-based GSA were conducted on a validated mechanistic primary drying model to estimate the impact of several model input parameters on two output variables, the product temperature at the sublimation front T i and the sublimation rate ṁ sub . T s was identified as most influential parameter on both T i and ṁ sub , followed by P c and the dried product mass transfer resistance α Rp for T i and ṁ sub , respectively. The GSA findings were experimentally validated for ṁ sub via a Design of Experiments (DoE) approach. The results indicated that GSA is a very useful tool for the evaluation of the impact of different process variables on the model outcome, leading to essential process knowledge, without the need for time-consuming experiments (e.g., DoE). Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Dry powder inhaler formulation of high-payload antibiotic nanoparticle complex intended for bronchiectasis therapy: Spray drying versus spray freeze drying preparation.

    Science.gov (United States)

    Yu, Hong; Teo, Jeanette; Chew, Jia Wei; Hadinoto, Kunn

    2016-02-29

    Inhaled nano-antibiotics have recently emerged as the promising bronchiectasis treatment attributed to the higher and more localized antibiotic exposure generated compared to native antibiotics. Antibiotic nanoparticle complex (or nanoplex in short) prepared by self-assembly complexation with polysaccharides addresses the major drawbacks of existing nano-antibiotics by virtue of its high payload and cost-effective preparation. Herein we developed carrier-free dry powder inhaler (DPI) formulations of ciprofloxacin nanoplex by spray drying (SD) and spray freeze drying (SFD). d-Mannitol and l-leucine were used as the drying adjuvant and aerosol dispersion enhancer, respectively. The DPI formulations were evaluated in vitro in terms of the (1) aerosolization efficiency, (2) aqueous reconstitution, (3) antibiotic release, and (4) antimicrobial activity against respiratory pathogen Pseudomonas aeruginosa. The SFD powders exhibited superior aerosolization efficiency to their SD counterparts in terms of emitted dose (92% versus 66%), fine particle fraction (29% versus 23%), and mass median aerodynamic diameter (3 μm versus 6 μm). The superior aerosolization efficiency of the SFD powders was attributed to their large and porous morphology and higher l-leucine content. While the SFD powders exhibited poorer aqueous reconstitution that might jeopardize their mucus penetrating ability, their antibiotic release profile and antimicrobial activity were not adversely affected. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Inhalable Spray-Freeze-Dried Powder with L-Leucine that Delivers Particles Independent of Inspiratory Flow Pattern and Inhalation Device.

    Science.gov (United States)

    Otake, Hiroko; Okuda, Tomoyuki; Hira, Daiki; Kojima, Haruyoshi; Shimada, Yasuhiro; Okamoto, Hirozazu

    2016-04-01

    The purpose of this study was to develop inhalable particles that can reach deep into the lungs efficiently independent of inhalation patterns of patients and inhalation devices. We prepared porous particles including L-leucine (Leu), a dispersive agent, by a spray-freeze-drying (SFD) method and examined the influence of inspiratory flow patterns and inhalation devices with various inhalation resistances. Four types of SFD powder with different Leu contents (0-10%) were prepared. Scanning electron microscopy and laser diffraction were used to measure the morphology and size distribution of the powders. In-vitro inhalation characteristics were determined using a twin-stage liquid impinger equipped with an inspiratory flow pattern simulator. The effects of Leu on the adhesion force and electrostatic property of the particles were evaluated. The inhalation performance of the powders was improved by the addition of Leu. The powders with Leu showed a high inhalation performance regardless of inspiratory flow patterns and devices. The addition of Leu decreased the adhesion force and increased the surface potential of the powders. The SFD particles with Leu showed high inhalation performance regardless of the inhalation patterns and devices, which was attributed to the decreased adhesion force between particles and increased dispersibility.

  3. A Comparison between Use of Spray and Freeze Drying Techniques for Preparation of Solid Self-Microemulsifying Formulation of Valsartan and In Vitro and In Vivo Evaluation

    Directory of Open Access Journals (Sweden)

    Sanjay Kumar Singh

    2013-01-01

    Full Text Available The objective of the present study was to develop self micro emulsifying formulation (SMEF of valsartan to improve its oral bioavailability. The formulations were screened on the basis of solubility, stability, emulsification efficiency, particle size and zeta potential. The optimized liquid SMEF contains valsartan (20% w/w, Capmul MCM C8 (16% w/w, Tween 80 (42.66% w/w and PEG 400 (21.33% w/w as drug, oil, surfactant and co-surfactant, respectively. Further, Liquid SMEF was adsorbed on Aerosol 200 by spray and freeze drying methods in the ratio of 2 : 1 and transformed into free flowing powder. Both the optimized liquid and solid SMEF had the particle size <200 nm with rapid reconstitution properties. Both drying methods are equally capable for producing stable solid SMEF and immediate release of drug in in vitro and in vivo conditions. However, the solid SMEF produced by spray drying method showed high flowability and compressibility. The solid state characterization employing the FTIR, DSC and XRD studies indicated insignificant interaction of drug with lipid and adsorbed excipient. The relative bioavailability of solid SMEF was approximately 1.5 to 3.0 folds higher than marketed formulation and pure drug. Thus, the developed solid SMEF illustrates an alternative delivery of valsartan as compared to existing formulations with improved bioavailability.

  4. Localization of tritiated 1-(2, 4-dichlorobenzyl)-1H-indazole-3-carboxylic acid ([3H] AF 1890) in rat testis using freeze-drying autoradiography

    International Nuclear Information System (INIS)

    Hilderbrandt-Stark, H.E.; Mills, J.W.; Fawcett, D.W.

    1982-01-01

    Tritiated 1-(2, 4-dichlorobenzyl)- 1 H-indazole-3-carboxylic acid ([ 3 H]AF 1890) was localized within rat testis using freeze-drying autoradiographic techniques. Ligated seminiferous tubule preparations were exposed in vitro to 80 microCi of [ 3 H]AF 1890 in the absence or presence of excess unlabeled AF 1890 for 30 min at 31 degrees C. Autoradiographs showed a generalized distribution of silver grains over the seminiferous epithelium, in the tubular lumen, and in the interstitial spaces. In addition, clusters of grains were concentrated over the seminiferous epithelium in regions of spermatid heads and tails and in the basal portion of the Sertoli cell cytoplasm, and over Leydig cells in the interstitial space. The generalized distribution was reduced and the grain clusters eliminated by incubation in an excess of unlabeled AF 1890. [ 3 H]inulin was used to assess the effectiveness of the tubular ligation because inulin does not normally penetrate the blood-testis barrier. This extracellular marker was not localized in the tubular lumen or in the seminiferous epithelium. Therefore, the labeling observed with [ 3 H]AF 1890 indicates that this compound crosses the blood-testis barrier

  5. Preservation of posterior mandibular extraction site with allogeneic demineralized, freeze-dried bone matrix and calcium sulphate graft binder before eventual implant placement: a case series.

    Science.gov (United States)

    Almasri, Mazen; Camarda, Aldo-Joseph; Ciaburro, Hugo; Chouikh, Fairouz; Dorismond, Sarah-Jane

    2012-01-01

    This case series reports short- and long-term healing, before and after placement of an implant, in posterior mandibular extraction sites grafted with demineralized, freeze-dried bone matrix (DFDBM) allograft mixed with calcium sulphate graft binder. Three patients who underwent surgical extraction of a posterior mandibular molar experienced partial loss of the buccal bone plate at the extraction site. Alveolar bone reconstruction with a DFDBM allograft mixed with calcium sulphate graft binder was performed immediately. The graft was covered with a biodegradable regenerative membrane. For each of the 3 patients, the implant and healing abutment were placed after 6, 9 and 12 months, respectively, followed by crown placement 3, 5 and 5 months later, respectively. The implants were periodically re-evaluated, both clinically and radiographically, between 10 and 39 months after final insertion of the crown. An implant stability device was used to evaluate the long-term biological and functional stability of the implants. Upon exposure and implant placement, the grafted alveolar ridge in all patients presented appropriately sized, dense and well-vascularized bone, wide enough to receive the planned wide-platform implant. The long-term interface stability quotient ranged from 87 to 90. Posterior mandibular extraction sites with compromised buccal alveolar bone may be effectively managed by immediate alveolar augmentation using a mixture of DFDBM allograft and calcium sulphate graft binder. This approach provides ideal alveolar form and consistency for eventual placement of the implant.

  6. Mechanical performance and thermal stability of glass fiber reinforced silica aerogel composites based on co-precursor method by freeze drying

    Science.gov (United States)

    Zhou, Ting; Cheng, Xudong; Pan, Yuelei; Li, Congcong; Gong, Lunlun; Zhang, Heping

    2018-04-01

    In order to maintain the integrity, glass fiber (GF) reinforced silica aerogel composites were synthesized using methltrimethoxysilane (MTMS) and water glass co-precursor by freeze drying method. The composites were characterized by scanning electron microscopy, Brunauer-Emmett-Teller analysis, uniaxial compressive test, three-point bending test, thermal conductivity analysis, contact angle test, TG-DSC analysis. It was found that the molar ratio of MTMS/water glass could significantly affect the properties of composites. The bulk density and thermal conductivity first decreased and then increased with the increasing molar ratio. The composites showed remarkable mechanical strength and flexibility compared with pure silica aerogel. Moreover, when the molar ratio is 1.8, the composites showed high specific surface area (870.9 m2/g), high contact angle (150°), great thermal stability (560 °C) and low thermal conductivity (0.0248 W/m·K). These outstanding properties indicate that GF/aerogels have broad prospects in the field of thermal insulation.

  7. Preparation of redispersible liposomal dry powder using an ultrasonic spray freeze-drying technique for transdermal delivery of human epithelial growth factor.

    Science.gov (United States)

    Yin, Fei; Guo, Shiyan; Gan, Yong; Zhang, Xinxin

    2014-01-01

    In this work, an ultrasonic spray freeze-drying (USFD) technique was used to prepare a stable liposomal dry powder for transdermal delivery of recombinant human epithelial growth factor (rhEGF). Morphology, particle size, entrapment efficiency, in vitro release, and skin permeability were systematically compared between rhEGF liposomal dry powder prepared using USFD and that prepared using a conventional lyophilization process. Porous and spherical particles with high specific area were produced under USFD conditions. USFD effectively avoided formation of ice crystals, disruption of the bilayer structure, and drug leakage during the liposome drying process, and maintained the stability of the rhEGF liposomal formulation during storage. The reconstituted rhEGF liposomes prepared from USFD powder did not show significant changes in morphology, particle size, entrapment efficiency, or in vitro release characteristics compared with those of rhEGF liposomes before drying. Moreover, the rhEGF liposomal powder prepared with USFD exhibited excellent enhanced penetration in ex vivo mouse skin compared with that for powder prepared via conventional lyophilization. The results suggest that ultrasonic USFD is a promising technique for the production of stable protein-loaded liposomal dry powder for application to the skin.

  8. Freeze-dried strawberry powder improves lipid profile and lipid peroxidation in women with metabolic syndrome: baseline and post intervention effects

    Directory of Open Access Journals (Sweden)

    Betts Nancy M

    2009-09-01

    Full Text Available Abstract Background Strawberry flavonoids are potent antioxidants and anti-inflammatory agents that have been shown to reduce cardiovascular disease risk factors in prospective cohort studies. Effects of strawberry supplementation on metabolic risk factors have not been studied in obese populations. We tested the hypothesis that freeze-dried strawberry powder (FSP will lower fasting lipids and biomarkers of oxidative stress and inflammation at four weeks compared to baseline. We also tested the tolerability and safety of FSP in subjects with metabolic syndrome. FSP is a concentrated source of polyphenolic flavonoids, fiber and phytosterols. Methods Females (n = 16 with 3 features of metabolic syndrome (waist circumference >35 inches, triglycerides > 150 mg/dL, fasting glucose > 100 mg/dL and 130/85 mm Hg were enrolled in the study. Subjects consumed two cups of the strawberry drink daily for four weeks. Each cup had 25 g FSP blended in water. Fasting blood draws, anthropometrics, dietary analyses, and blood pressure measurements were done at baseline and 4 weeks. Biomarkers of oxidative stress and inflammation were measured using ELISA techniques. Plasma ellagic acid was measured using HPLC-UV techniques. Results Total cholesterol and LDL-cholesterol levels were significantly lower at 4 weeks versus baseline (-5% and -6%, respectively, p

  9. Elimination of bicarbonate interference in the binding of U(VI) in mill-waters to freeze-dried Chlorella vulgaris

    International Nuclear Information System (INIS)

    Greene, B.; Henzl, M.T.; Hosea, J.M.; Darnall, D.W.

    1986-01-01

    Freeze-dried preparations of Chlorella vulgaris will accumulate U(Vl) from alkaline, bicarbonate-containing waters collected from uranium mill process streams, provided that the pH is pre-adjusted to between 4.0 and 6.0. Bicarbonate ion complexes the uranyl ion in these waters and seriously interferes with the binding of U(Vl) to the algal cells at pH values above 6.0. No binding of U(Vl) to the algae occurred at the natural pH of 8.0 when Chlorella vulgaris was suspended in untreated mull-waters containing up to 2.5 x 10 -4 M U(Vl). However, when the pH of these waters was lowered from 8.0 to near 5.0, with nitric acid, nearly quantitative binding of U(Vl) to the alga was achieved. Binding is rapid and largely unaffected by ions including Na + , Cl - , NO 3 - , - OAc, and SO 4 2- . Our results indicate that provided steps are taken to eliminate bicarbonate interference, such as adjustment of the pH to near 5.0, dried algal biomass could prove useful for the removal and recovery of U(Vl) from high carbonate-containing waters

  10. Safety assessment of freeze-dried powdered Tenebrio molitor larvae (yellow mealworm) as novel food source: Evaluation of 90-day toxicity in Sprague-Dawley rats.

    Science.gov (United States)

    Han, So-Ri; Lee, Byoung-Seok; Jung, Kyung-Jin; Yu, Hee-Jin; Yun, Eun-Young; Hwang, Jae Sam; Moon, Kyoung-Sik

    2016-06-01

    Worldwide demand for novel food source has grown and edible insects are a promising food sources for humans. Tenebrio molitor, as known as yellow mealworm, has advantages of being rich in protein, and easy to raise as a novel food source. The objective of this study was to evaluate subchronic toxicity, including potential hypersensitivity, of freeze-dried powdered T. molitor larvae (fdTML) in male and female Sprague-Dawley rats. The fdTML was administered orally once daily at dose levels of 0, 300, 1000 and 3000 mg/kg/day for 90 days. A toxicological assessment was performed, which included mortality, clinical signs, body and organ weights, food consumption, ophthalmology, urinalysis, hematology, serum chemistry, gross findings, histopathologic examination and allergic reaction. There were no fdTML- related findings in clinical signs, urinalysis, hematology and serum chemistry, gross examination, histopathologic examination or allergic reaction. In conclusion, the No Observed Adverse Effect Level (NOAEL) for fdTML was determined to be in excess of 3000 mg/kg/day in both sexes of rats under the experimental conditions of this study. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Freeze-dried strawberry and blueberry attenuates diet-induced obesity and insulin resistance in rats by inhibiting adipogenesis and lipogenesis.

    Science.gov (United States)

    Aranaz, Paula; Romo-Hualde, Ana; Zabala, María; Navarro-Herrera, David; Ruiz de Galarreta, Marina; Gil, Ana Gloria; Martinez, J Alfredo; Milagro, Fermín I; González-Navarro, Carlos J

    2017-11-15

    Obesity and type 2-diabetes are becoming a worldwide health problem, reiterating the importance of alternative therapies to tackle their progression. Here, we hypothesized that supplementation of diet with 6% w/w of a freeze-dried strawberry-blueberry (5 : 1) powder (FDSB) could exert beneficial metabolic effects on Wistar rats. FDSB-supplemented animals experienced significantly reduced body weight gain, food efficiency and visceral adiposity accumulation in two independent experiments. FDSB supplementation also contributed to lower area under the curve after an intraperitoneal GTT and reduced serum insulin levels and an insulin resistance index (IR-HOMA) in HFS diet-fed animals, together with reduced plasma MCP-1 inflammation marker concentrations. Gene expression analysis in retroperitoneal adipocytes from experiment 1 and 3T3-L1 cells showed that FDSB inhibited adipogenesis and lipogenesis through down-regulation of Pparg, Cebpa, Lep, Fasn, Scd-1 and Lpl gene expression. Untargeted metabolomics identified the cis isomer of resveratrol-3-glucoside-sulphate as a metabolite differentially increased in FDSB-treated serum samples, which corresponds to a strawberry metabolite that could be considered a serum biomarker of FDSB-intake. Our results suggest that FDSB powder might be useful for treatment/prevention of obesity-related diseases.

  12. A freeze dried kit formulation for the preparation of 99m Tc labelled human polyclonal IgG for the detection of infection and inflammation

    International Nuclear Information System (INIS)

    Pedraza L, M.

    1996-01-01

    A freeze dried kit formulation for the preparation of 99m Tc-labelled human polyclonal IgG for the detection of infection and inflammation employing direct methods for protein labeling was developed. The method comprises reduction of intrinsic disulphide bridges within the antibody molecule by the use of the reductant 2-mercaptoethanol. Following a subsequent purification, the resulting reduced antibody is labeled via Sn 2+ reduction of pertechnetate in the presence of a weak competing ligand ethane-1-hydroxy-1,1-diphosphonate (EHDP). High labeling efficiencies (>90%) were obtained with high in vitro stability and without effect upon antibody immunoreactivity. Methods of analysis were also established permitting identification of radiochemical impurities which may be present in radiopharmaceutical solution. 99m Tc-polyclonal IgG prepared by the kit method was evaluated for scintigraphic localization of inflammatory lesions and abscesses in rabbits. Data demonstrated that the 99m Tc-polyclonal IgG after kit-reconstitution shows excellent stability and is an effective imaging agent of infection and/or inflammation. (Author)

  13. Danube Soya – Improving European GM-free soya supply for food and feed

    OpenAIRE

    Krön Matthias; Bittner Ursula

    2015-01-01

    The Danube Soya Association is an international, voluntary, non-profit, non-governmental association promoting sustainable and GMO**-free soya production along the Danube River Basin – from Switzerland to the Black Sea. Founded in 2012 the association counts today more than 200 members from the whole value chain and civil society in 16 European countries. The members share the vision of a protein transition towards more European...

  14. Transbilayer distribution and mobility of phosphatidylcholine in intact erythrocyte membranes. A study with phosphatidylcholine exchange protein

    NARCIS (Netherlands)

    van Meer, G.; Poorthuis, B. J.; Wirtz, K. W.; Op den Kamp, J. A.; van Deenen, L. L.

    1980-01-01

    1. The exchange of phosphatidylcholine between intact human or rat erythrocytes and rat liver microsomes was greatly stimulated by phosphatidylcholine-specific exchange proteins from rat liver and beef liver. It was found, however, that compared to the exchange reaction between phospholipid vesicles

  15. Transbilayer distribution and mobility of phosphatidylcholine in intact erythrocyte membranes. A study with phosphatidylcholine exchange protein

    NARCIS (Netherlands)

    van Meer, G.|info:eu-repo/dai/nl/068570368; Poorthuis, B.J.H.M.; Wirtz, K.W.A.|info:eu-repo/dai/nl/068427956; op den Kamp, J.A.F.; van Deenen, L.L.M.

    1980-01-01

    The exchange of phosphatidylcholine between intact human or rat erythrocytes and rat liver microsomes was greatly stimulated by phosphatidylcholine-specific exchange proteins from rat liver and beef liver. It was found, however, that compared to the exchange reaction between phospholipid vesicles

  16. Use of a non-linear method for including the mass uncertainty of gravimetric standards and system measurement errors in the fitting of calibration curves for XRFA freeze-dried UNO3 standards

    International Nuclear Information System (INIS)

    Pickles, W.L.; McClure, J.W.; Howell, R.H.

    1978-05-01

    A sophisticated nonlinear multiparameter fitting program was used to produce a best fit calibration curve for the response of an x-ray fluorescence analyzer to uranium nitrate, freeze dried, 0.2% accurate, gravimetric standards. The program is based on unconstrained minimization subroutine, VA02A. The program considers the mass values of the gravimetric standards as parameters to be fit along with the normal calibration curve parameters. The fitting procedure weights with the system errors and the mass errors in a consistent way. The resulting best fit calibration curve parameters reflect the fact that the masses of the standard samples are measured quantities with a known error. Error estimates for the calibration curve parameters can be obtained from the curvature of the ''Chi-Squared Matrix'' or from error relaxation techniques. It was shown that nondispersive XRFA of 0.1 to 1 mg freeze-dried UNO 3 can have an accuracy of 0.2% in 1000 s

  17. Effects of soya fatty acids on cassava ethanol fermentation.

    Science.gov (United States)

    Xiao, Dongguang; Wu, Shuai; Zhu, Xudong; Chen, Yefu; Guo, Xuewu

    2010-01-01

    Ethanol tolerance is a key trait of microbes in bioethanol production. Previous studies have shown that soya flour contributed to the increase of ethanol tolerance of yeast cells. In this paper, the mechanism of this ethanol tolerance improvement was investigated in cassava ethanol fermentation supplemented with soya flour or defatted soya flour, respectively. Experiment results showed that ethanol tolerance of cells from soya flour supplemented medium increased by 4-6% (v/v) than the control with defatted soya flour. Microscopic observation found that soya flour can retain the cell shape while dramatic elongations of cells were observed with the defatted soya flour supplemented medium. Unsaturated fatty acids (UFAs) compositions of cell membrane were analyzed and the UFAs amounts increased significantly in all tested strains grown in soya flour supplemented medium. Growth study also showed that soya flour stimulated the cell growth rate by approximately tenfolds at 72-h fermentation. All these results suggested that soya fatty acids play an important role to protect yeast cells from ethanol stress during fermentation process.

  18. A comparison study on the behavior of human endometrial stem cell-derived osteoblast cells on PLGA/HA nanocomposite scaffolds fabricated by electrospinning and freeze-drying methods.

    Science.gov (United States)

    Namini, Mojdeh Salehi; Bayat, Neda; Tajerian, Roxana; Ebrahimi-Barough, Somayeh; Azami, Mahmoud; Irani, Shiva; Jangjoo, Saranaz; Shirian, Sadegh; Ai, Jafar

    2018-03-27

    An engineered tissue structure is an artificial scaffold combined with cells and signaling factors. Among various polymers, the polylactide-co-glycolide/hydroxyapatite (PLGA/HA) has attracted much attention due to their optimal properties. The aim of this study was to study the behavior of human endometrial stem cell (hEnSC)-derived osteoblast cells cultured on PLGA/HA nanocomposite scaffolds. hEnSCs were isolated and exposed to osteogenic media for 21 days. Differentiated cells were cultured on PLGA/HA synthetic scaffolds. The PLGA/HA-based nanocomposite scaffolds were fabricated using either electrospinning or freeze-drying methods. Behavior of the cells was evaluated a week after seeding hEnSC-derived osteoblast-like cells on these scaffolds. Osteogenesis was investigated in terms of alkaline phosphatase activity, gene expression, immunocytochemistry (ICC), proliferation, and scanning electron microscopy (SEM). Moreover, scaffold properties, such as pore size and morphology of the cells, onto the scaffolds were evaluated using SEM. Furthermore, biocompatibility of these scaffolds was confirmed by 3-(4,5-dimethylthiazoyl-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The matrix mineralization was proved by alizarin red staining, and the osteogenic media-treated cultures positively expressed osteocalcin and osteopontin markers. Moreover, qRT-PCR results confirmed the positive gene expression of osteopontin and osteonectin in the differentiated osteoblast-like cells. The results of behavior assessment of the cultured cells on electrospinning and freeze-dried scaffolds showed that the behavior of the cultured cells on the freeze-dried PLGA/HA scaffolds was significantly better than the electrospinning PLGA/HA scaffolds. It has been shown that the freeze-dried PLGA/HA nanocomposite scaffolds can appropriately support the attachment and proliferation of the differentiated osteoblast cells and are a suitable candidate for bone tissue engineering.

  19. Comparison of bile salt/phosphatidylcholine mixed micelles in solubilization to sterols and stability

    Directory of Open Access Journals (Sweden)

    Guo Q

    2016-11-01

    Full Text Available Qin Guo,1,* Jie Cai,1,2,* Pengyu Li,1 Dongling Xu,1 Xiaomin Ni,1 Hui Wen,3 Dan Liu,3 Suizhen Lin,3 Haiyan Hu1 1School of Pharmaceutical Sciences, Sun Yat-sen University, 2Guangzhou First People’s Hospital, Guangzhou Medical University, 3Guangzhou Cellprotek Pharmaceutical Co., Ltd., Science Park, Guangzhou, People’s Republic of China *These authors contributed equally to this work Abstract: Androst-3β,5α,6β-triol (Triol is a promising neuroprotective agent, but its poor solubility restricts its development into parenteral preparations. In this study, Triol is significantly solubilized by bile salt/phosphatidylcholine mixed micelles (BS/PC-MM. All BS/PC-MM systems are tested to remarkably improve the drug solubility with various stabilities after drug loading. Among them, the sodium glycocholate (SGC/egg phosphatidylcholine (EPC system with 2:1 ratio in weight and the total concentration of SGC and EPC of 100 mg/mL is proved to produce stable mixed micelles with high drug loading. It is found that the stability of drug-loaded mixed micelles is quite different, which might be related to the change in critical micelle concentration (CMC after incorporating drugs. SGC/EPC and SGC/soya phosphatidylcholine (SPC remain transparent under accelerated conditions and manifest a decreased CMC (dropping from 0.105 to 0.056 mg/mL and from 0.067 to 0.024 mg/mL, respectively. In contrast, swine bile acid-sodium salt (SBA-Na/PC and sodium deoxycholate (SDC/PC are accompanied by drug precipitation and reached the maximum CMC on the first and the third days, respectively. Interestingly, the variation of CMC under accelerated testing conditions highly matches the drug-precipitating event in the primary stability experiment. In brief, the bile salt/phosphatidylcholine system exists as a potential strategy of improving sterol drug solubility. CMC variation under accelerated testing conditions might be a simple and easy method to predict the stability of

  20. In-line near infrared spectroscopy during freeze-drying as a tool to measure efficiency of hydrogen bond formation between protein and sugar, predictive of protein storage stability.

    Science.gov (United States)

    Mensink, Maarten A; Van Bockstal, Pieter-Jan; Pieters, Sigrid; De Meyer, Laurens; Frijlink, Henderik W; van der Voort Maarschalk, Kees; Hinrichs, Wouter L J; De Beer, Thomas

    2015-12-30

    Sugars are often used as stabilizers of protein formulations during freeze-drying. However, not all sugars are equally suitable for this purpose. Using in-line near-infrared spectroscopy during freeze-drying, it is shown here that hydrogen bond formation during freeze-drying, under secondary drying conditions in particular, can be related to the preservation of the functionality and structure of proteins during storage. The disaccharide trehalose was best capable of forming hydrogen bonds with the model protein, lactate dehydrogenase, thereby stabilizing it, followed by the molecularly flexible oligosaccharide inulin 4kDa. The molecularly rigid oligo- and polysaccharides dextran 5kDa and 70kDa, respectively, formed the least amount of hydrogen bonds and provided least stabilization of the protein. It is concluded that smaller and molecularly more flexible sugars are less affected by steric hindrance, allowing them to form more hydrogen bonds with the protein, thereby stabilizing it better. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Effect of mangosteen peel extract combined with demineralized freezed-dried bovine bone xenograft on osteoblast and osteoclast formation in post tooth extraction socket

    Directory of Open Access Journals (Sweden)

    Utari Kresnoadi

    2016-12-01

    Full Text Available Background: Tooth extraction, a common procedure in dentistry, can cause bone resorption during socket healing. Therefore, it is important to perform socket preservation procedure to maintain alveolar bone. Providing a combination of mangosteen peel extract with demineralized freezed-dried bovine bone xenograft (DFDBBX in tooth extraction socket was expected to accelerate alveol bone formation. Purpose: This study aims to determine the effect of mangosteen peel extract combined with DFDBBX introduced into the socket of post tooth extraction on the formation of osteoblasts and osteoclasts. Method: Twenty-eight (28 Cavia cobayas were divided into four groups. Extraction to the lower left incisor of Cavia cobaya was performed. The extraction socket was filled with 25 gram of PEG (group I as a control, active materials consisted of mangosteen peel extract and DFDBBX 0.5% (group II, active materials consisted of mangosteen peel extract and DFDBBX 1% (group III, and active materials consisted of mangosteen peel extract and DFDBBX 2% (group IV. After thirty days, those Cavia cobayas were sacrificed. By using HE on Histopatological examination, the number of osteoblasts and osteoclasts were measured by light microscope with 400 times of magnification. The statistical analysis was then performed using oneway Anova & TukeyHSD test. Result: The component active materials consisted of mangosteen peel extract and DFDBBX 2% had the most significant results related to the formation of osteoblasts and osteoclasts. Conclusion: Mangosteen peel extract combined with DFDBBX can increase osteoblasts and decrease osteoclasts in the socket of tooth extraction in Cavia cobaya. The combination of mangosteen peel extract and DFDBBX 2% is the most effective material in increasing osteoblast and decreasing osteoclast.

  2. Histologic Evaluation of Wound Healing After Ridge Preservation With Cortical, Cancellous, and Combined Cortico-Cancellous Freeze-Dried Bone Allograft: A Randomized Controlled Clinical Trial.

    Science.gov (United States)

    Demetter, Randy S; Calahan, Blaine G; Mealey, Brian L

    2017-09-01

    Cortical and cancellous mineralized freeze-dried bone allografts (FDBA) are available for use in alveolar ridge preservation after tooth extraction. There are currently no data regarding use of a combination 50%/50% cortico-cancellous FDBA compared with a 100% cortical or 100% cancellous FDBA in ridge preservation. The primary objective of this study is to dimensionally and histologically evaluate healing after ridge preservation in non-molar sites using 50%/50% cortico-cancellous FDBA versus 100% cortical and 100% cancellous FDBA. Sixty-six patients requiring extraction of a non-molar tooth were enrolled and randomized into three groups to receive ridge preservation with the following: 1) 100% cortical FDBA; 2) 100% cancellous FDBA; or 3) 50%/50% cortico-cancellous FDBA. After 18 to 20 weeks of healing, a biopsy was harvested, and an implant was placed. The alveolar ridge was measured pre- and postoperatively to evaluate change in ridge height and width. Percentages of vital bone, residual graft, and connective tissue (CT)/other were determined via histomorphometric analysis. Histomorphometric analysis revealed no significant differences among groups regarding percentage of vital bone or CT/other. The 100% cortical FDBA group had significantly greater residual graft material (P = 0.04). Dimensional analysis revealed no significant between-group differences in any parameter measured. To the best knowledge of the authors, this study offers the first histologic evidence demonstrating no significant difference in vital bone formation or dimensional changes among 50%/50% cortico-cancellous FDBA, 100% cortical FDBA, and 100% cancellous FDBA when used in ridge preservation of non-molar tooth sites.

  3. Microbial Diversity of a Camembert-Type Cheese Using Freeze-Dried Tibetan Kefir Coculture as Starter Culture by Culture-Dependent and Culture-Independent Methods

    Science.gov (United States)

    Mei, Jun; Guo, Qizhen; Wu, Yan; Li, Yunfei

    2014-01-01

    The biochemical changes occurring during cheese ripening are directly and indirectly dependent on the microbial associations of starter cultures. Freeze-dried Tibetan kefir coculture was used as a starter culture in the Camembert-type cheese production for the first time. Therefore, it's necessary to elucidate the stability, organization and identification of the dominant microbiota presented in the cheese. Bacteria and yeasts were subjected to culture-dependent on selective media and culture-independent polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) analysis and sequencing of dominant bands to assess the microbial structure and dynamics through ripening. In further studies, kefir grains were observed using scanning electron microscopy (SEM) methods. A total of 147 bacteria and 129 yeasts were obtained from the cheese during ripening. Lactobacillus paracasei represents the most commonly identified lactic acid bacteria isolates, with 59 of a total of 147 isolates, followed by Lactococcus lactis (29 isolates). Meanwhile, Kazachstania servazzii (51 isolates) represented the mainly identified yeast isolate, followed by Saccharomyces cerevisiae (40 isolates). However, some lactic acid bacteria detected by sequence analysis of DGGE bands were not recovered by plating. The yeast S. cerevisiae and K. servazzii are described for the first time with kefir starter culture. SEM showed that the microbiota were dominated by a variety of lactobacilli (long and curved) cells growing in close association with a few yeasts in the inner portion of the grain and the short lactobacilli were observed along with yeast cells on the exterior portion. Results indicated that conventional culture method and PCR-DGGE should be combined to describe in maximal detail the microbiological composition in the cheese during ripening. The data could help in the selection of appropriate commercial starters for Camembert-type cheese. PMID:25360757

  4. Preparation of liposomes containing zedoary turmeric oil using freeze-drying of liposomes via TBA/water cosolvent systems and evaluation of the bioavailability of the oil.

    Science.gov (United States)

    Yang, Zhiwen; Yu, Songlin; Fu, Dahua

    2010-02-01

    The purpose of this study was to enhance the absorption of zedoary turmeric oil (ZTO) in vivo and develop new formulations of a water-insoluble oily drug. This study described a method for preparing ZTO liposomes, which involved freeze-drying (FD) of liposomes with TBA/water cosolvent systems. The TBA/water cosolvent systems were used to investigate a feasible method of liposomes manufacture; the two factors, sugar/lipid mass ratio and TBA content (concentration), of the preparation process were evaluated in this study. The results showed that the addition of TBA content could significantly enhance the sublimation of ice resulting in short FD cycles time, and reduce the entrapment efficiency of liposomes. In addition, the residual TBA solvents levels were determined to be less than 0.37% under all optimum formulations and processing conditions. Several physical properties of liposomes were examined by H-600 transmission electron microscope (TEM) and zetamaster analyser system. The results revealed that the liposomes were smooth and spherical with an average particle size of 457 +/- 7.8 nm and the zeta potential was more than 3.65 Mv. The bioavailability of the liposomes was evaluated in rabbits, compared with the conventional self-emulsifying formulation for oral administration. Compared with the conventional self-emulsifying formulation, the plasma concentration-time profiles with improved sustained-release characteristics were achieved after oral administration of the liposomes with a bioavailability of 257.7% (a good strategy for improving the bioavailability of an oily drug). In conclusion, the present experimental findings clearly demonstrated the usefulness of ZTO liposome vesicles in improving therapeutic efficacy by enhancing oral bioavailability. Our study offered an alternative method for designing sustained-release preparations of oily drugs.

  5. Clinical and biometrical evaluation of socket preservation using demineralized freeze-dried bone allograft with and without the palatal connective tissue as a biologic membrane.

    Science.gov (United States)

    Moghaddas, Hamid; Amjadi, Mohammad Reza; Naghsh, Narges

    2012-11-01

    Alveolar ridge preservation following tooth extraction has the ability to maintain the ridge dimensions and allow the implant placement in an ideal position fulfilling both functional and aesthetic results. The aim of this study was to evaluate the efficacy of the palatal connective tissue as a biological membrane for socket preservation with demineralized freeze-dried bone allograft (DFDBA). Twelve extraction sites were treated with DFDBA with (case group) and without (control group) using autogenous palatal connective tissue membrane before placement of implants. Alveolar width and height, amount of keratinized tissue, and gingival level were measured at pre-determined points using a surgical stent at two times, the time of socket preservation surgery. In both groups a decrease in all socket dimensions was found. The average decrease in socket width, height, keratinized tissue, and gingival level in case group was 1.16, 0.72, 3.58, and 1.27 mm, and in control group was 2.08, 0.86, 4.52, and 1.58 mm respectively. Statistical analysis showed that decrease in socket width (P = 0.012), keratinized tissue (P ≤ 0.001), and gingival level (P = 0.031) in case group was significantly lower than that of the control group. Results showed no meaningful difference in socket height changes when compared with case and control groups (P = 0.148). Under the limits of this study, connective tissue membrane could preserve socket width, amount of keratinized tissue, and the gingival level more effectively than DFDBA alone.

  6. A randomized controlled evaluation of alveolar ridge preservation following tooth extraction using deproteinized bovine bone mineral and demineralized freeze-dried bone allograft.

    Science.gov (United States)

    Sadeghi, Rokhsareh; Babaei, Maryam; Miremadi, S Asghar; Abbas, Fatemeh Mashadi

    2016-01-01

    Alveolar ridge preservation could be performed immediately following tooth extraction to limit dimensional changes of alveolar process due to bone resorption. The aim of this study was to compare the clinical and histologic outcomes of socket preservation using two different graft materials; deproteinized bovine bone mineral (DBBM) and demineralized freeze-dried bone allograft (DFDBA) with absorbable collagen membrane. Twenty extraction sockets in 20 patients were randomly divided into 2 treatment groups: 10 sockets were augmented with DBBM and collagen membrane whereas 10 sockets were filled with DFDBA and covered by collagen membrane. Primary closure was achieved over extraction sockets by flap advancement. Horizontal and vertical ridge dimensional changes were assessed at baseline and after 4-6 months at the time of implant placement. For histological and histomorphometrical analysis, bone samples were harvested from the augmented sites with trephine during implant surgery. All data were analyzed using SPSS version 18 (α=0.05). Clinical measurements revealed that average horizontal reduction was 2.3 ± 0.64 mm for DFDBA and 2.26 ± 0.51 mm for DBBM. Mean vertical ridge resorption at buccal side was 1.29 ± 0.68 mm for DFDBA and 1.1 ± 0.17 mm for DBBM. Moreover, mean vertical ridge reduction at lingual site was 0.41 ± 0.38 mm and 0.35 ± 0.34 mm for DFDBA and DBBM, respectively. No significant differences were seen between two groups in any of those clinical parameters. Histologic analysis showed statistically significant more new bone deposition for DFDBA compared to DBBM (34.49 ± 3.19 vs. 18.76 ± 3.54) (P alveolar ridge preservation after tooth extraction, but there was more new bone formation and less residual graft particles in DFDBA group than in DBBM group.

  7. Histologic healing following tooth extraction with ridge preservation using mineralized versus combined mineralized-demineralized freeze-dried bone allograft: a randomized controlled clinical trial.

    Science.gov (United States)

    Borg, Tyler D; Mealey, Brian L

    2015-03-01

    Mineralized and demineralized freeze-dried bone allografts (FDBAs) are used in alveolar ridge (AR) preservation; however, each material has advantages and disadvantages. Combinations of allografts aimed at capitalizing on the advantages each offers are available. To date, there is no evidence to indicate if a combination allograft is superior in this application. The primary objective of this study is to histologically evaluate and compare healing of non-molar extraction sites grafted with either mineralized FDBA or a 70:30 mineralized:demineralized FDBA combination allograft in AR preservation. The secondary objective is to compare dimensional changes in ridge height and width after grafting with these two materials. Forty-two patients randomized into two equal groups received ridge preservation with either 100% mineralized FDBA (active control group) or the combination 70% mineralized: 30% demineralized allograft (test group). Sites were allowed to heal for 18 to 20 weeks, at which time core biopsies were obtained and dental implants were placed. AR dimensions were evaluated at the time of extraction and at implant placement, including change in ridge width and change in buccal and lingual ridge height. Histomorphometric analysis was performed to determine percentage of vital bone, residual graft, and connective tissue/other non-bone components. There was no significant difference between groups in AR dimensional changes. Combination allograft produced increased vital bone percentage (36.16%) compared to the FDBA group (24.69%; P = 0.0116). The combination allograft also had a significantly lower mean percentage of residual graft particles (18.24%) compared to FDBA (27.04%; P = 0.0350). This study provides the first histologic evidence showing greater new bone formation with a combination mineralized/demineralized allograft compared to 100% mineralized FDBA in AR preservation in humans. Combination allograft results in increased vital bone formation while

  8. Evaluation of bioactive glass and demineralized freeze dried bone allograft in the treatment of periodontal intraosseous defects: A comparative clinico-radiographic study

    Directory of Open Access Journals (Sweden)

    Kishore Kumar Katuri

    2013-01-01

    Full Text Available Aim: The purpose of this study was to evaluate the efficacy of demineralized freeze dried bone allograft (DFDBA and bioactive glass by clinically and radiographically in periodontal intrabony defects for a period of 12 months. Materials and Methods: Ten systemically healthy patients diagnosed with chronic periodontitis, with radiographic evidence of at least a pair of contralateral vertical osseous defects were included in this study. Defect on one-side is treated with DFDBA and the other side with bioactive glass. Clinical and radiographic measurements were made at baseline 6 month and 12 month after the surgery. Results: Compared to baseline, the 12 month results indicated that both treatment modalities resulted in significant changes in all clinical parameters (gingival index, probing depth, clinical attachment level (CAL and radiographic parameters (bone fill; P < 0.001FNx01. However, sites treated with DFDBA exhibited statistically significantly more changes compared to the bioactive glass in probing depth reduction (2.5 ± 0.1 mm vs. 1.8 ± 0.1 mm CAL gain 2.4 ± 0.1 mm versus 1.7 ± 0.2 mm; ( P < 0.001FNx01. At 12 months, sites treated with bioactive glass exhibited 56.99% bone fill and 64.76% bone fill for DFDBA sites, which is statistically significant ( P < 0.05FNx01. Conclusion: After 12 months, there was a significant difference between the two materials with sites grafted with DFDBA showing better reduction in probing pocket depth, gain in CAL and a greater percentage of bone fill when compared to that of bioactive glass.

  9. Formulation and In-Vitro and In-Vivo Evaluation of a Mucoadhesive Gel Containing Freeze Dried Black Raspberries: Implications for Oral Cancer Chemoprevention

    Science.gov (United States)

    Mallery, Susan R.; Stoner, Gary D.; Larsen, Peter E.; Fields, Henry W.; Rodrigo, Kapila A.; Schwartz, Steven J.; Tian, Qingguo; Dai, Jin; Mumper, Russell J.

    2008-01-01

    Purpose The purpose of these studies was to formulate mucoadhesive gels containing freeze dried black raspberries (FBR) and to determine optimum parameters for a subset of FBR bioactive compounds including anthocyanin stability, absorption and penetration in-vitro and in-vivo. Materials and Methods Berry gels were prepared having FBR at 5% and 10% w/w and final pHs ranging from 3.5 to 7.5. A HPLC assay was developed to quantify and determine the stability of the anthocyanins in the gels. A single time-point study was performed to determine anthocyanin uptake when the gels were applied to oral mucosa. Penetration of anthocyanins into human oral tissue explants was determined as a function of gel pH and FBR content. A HPLC-mass spectroscopy assay was utilized to quantify the anthocyanin levels in human oral tissue explants, saliva, and blood. Results The stability of anthocyanins in the gel was directly related to gel pH and storage temperature. Maximum stability of anthocyanins was found at lower pH (pH 3.5) and storage temperature (4°C). Anthocyanins contained in mucoadhesive berry gel formulations were readily absorbed into human oral mucosa tissue as evidenced by detectable blood levels within 5 min after gel application. There was a trend for greater penetration of anthocyanins into tissue explants for berry gels with a final pH of 6.5 versus pH 3.5. Conclusions Formulation and characterization of a novel gel formulation for local delivery of chemopreventive compounds to human oral mucosal tissues has been described. The results show anthocyanin stability was dependent upon gel pH and storage temperature and also demonstrate that the gel composition is well-suited for absorption and penetration into the target oral mucosal tissue site. PMID:17372698

  10. Kinetics of the Degradation of Anthocyanins, Phenolic Acids and Flavonols During Heat Treatments of Freeze-Dried Sour Cherry Marasca Paste

    Directory of Open Access Journals (Sweden)

    Zoran Zorić

    2014-01-01

    Full Text Available The effect of heating temperature (80–120 °C and processing time (5–50 min on the stability of anthocyanins (cyanidin-3-glucosylrutinoside, cyanidin-3-rutinoside and cyanidin- 3-glucoside, quercetin-3-glucoside and phenolic acids (chlorogenic, neochlorogenic, p-coumaric and ferulic acids in freeze-dried Marasca sour cherry pastes was studied. The degradation rates of individual anthocyanins, quercetin-3-glucoside and phenolic acids followed the first order reaction kinetics. Cyanidin-3-glucoside was found to be the most unstable among the anthocyanins, together with p-coumaric and neochlorogenic acids among other phenols. Activation energies for anthocyanin degradation ranged from 42 (cyanidin-3-glucosylrutinoside to 55 kJ/mol (cyanidin-3-glucoside, and for other phenols from 8.12 (chlorogenic acid to 27 kJ/mol (neochlorogenic acid. By increasing the temperature from 80 to 120 °C, the reaction rate constant of cyanidin-3-glucosylrutinoside increased from 2.2·10–2 to 8.5·10–2 min–1, of p-coumaric acid from 1.12·10–2 to 2.5·10–2 min–1 and of quercetin-3-glucoside from 1.5·10–2 to 2.6·10–2 min–1. The obtained results demonstrate that at 80°C the half-life of anthocyanins ranges from 32.10 min for cyanidin-3-glucosylrutinoside to 45.69 min for cyanidin-3-rutinoside, and of other phenolic compounds from 43.39 for neochlorogenic acid to 66.99 min for chlorogenic acid. The results show that the heating temperature and duration affect the anthocyanins considerably more than the other phenols in terms of degradation.

  11. Influence of freeze-drying and γ-irradiation in preclinical studies of flurbiprofen polymeric nanoparticles for ocular delivery using d-(+)-trehalose and polyethylene glycol

    Science.gov (United States)

    Ramos Yacasi, Gladys Rosario; García López, María Luisa; Espina García, Marta; Parra Coca, Alexander; Calpena Campmany, Ana Cristina

    2016-01-01

    This study investigated the suspension of poly(ε-caprolactone) nanoparticles as an ocular delivery system for flurbiprofen (FB-PεCL-NPs) in order to overcome the associated problems, such as stability, sterility, tolerance, and efficacy, with two different FB-PεCL-NP formulations. The formulations were stabilized with poloxamer 188 (1.66% and 3.5%) and submitted individually for freeze-drying and γ-irradiation with polyethylene glycol 3350 (PEG3350) and d-(+)-trehalose (TRE). Both formulations satisfied criteria according to all physicochemical parameters required for ocular pharmaceuticals. The FB-PεCL-NP formulations showed non-Newtonian behavior and sustained drug release. Ex vivo permeation analysis using isolated ocular pig tissues suggested that the presence of PEG3350 results in a reduction of FB transcorneal permeation. Moreover, TRE improved the penetration of FB across the cornea, especially after γ-irradiation. In addition, both formulations did not show a significant affinity in increasing FB transscleral permeation. Both formulations were classified as nonirritating, safe products for ophthalmic administration according to hen’s egg test-chorioallantoic membrane and Draize eye test. Furthermore, an in vivo anti-inflammatory efficacy test showed that irradiated FB-PεCL-NPs prepared with PEG3350 (IR-NPsPEG) have longer anti-inflammatory effects than those presented with irradiated FB-PεCL-NPs prepared with TRE (IR-NPsTRE). IR-NPsPEG showed a suitable physical stability after an aqueous reconstitution over >30 days. This study concludes that both formulations meet the Goldman’s criteria and demonstrate how irradiated nanoparticles, with innovative permeation characteristics, could be used as a feasible alternative to a flurbiprofen solution for ocular application in clinical trials. PMID:27601897

  12. Effects of bovine somatotropin (rbSt) concentration at different moisture levels on the physical stability of sucrose in freeze-dried rbSt/sucrose mixtures.

    Science.gov (United States)

    Sarciaux, J M; Hageman, M J

    1997-03-01

    The inherent instability of many proteins during freeze-drying and storage necessitates the addition of excipients to protect the proteins. It is emphasized in the literature that lyophilized sugar/protein composites should be stored at temperatures below their glass transition temperature (T(g)) to prevent crystallization of excipients. The influence of bovine somatotropin (rbSt) concentration on inhibition of sucrose crystallization at different relative humidities (RH) was of interest. Thermally modulated differential scanning calorimetry (MDSC) was used to measure T(g) and sucrose crystallization temperatures (T(c)) of the composites. Sorption isotherms of the various sucrose/rbSt mixtures were determined gravimetrically with a controlled atmosphere microbalance (CAM) and verified by Karl Fischer analysis of selected samples. The CAM was also used to determine lag times and sucrose crystal growth rates by monitoring weight losses resulting from water liberation upon crystallization of sucrose at 23 degrees C. Results obtained by MDSC indicate that the T(c) increased linearly from approximately 110 degrees C for pure sucrose to approximately 140 degrees C with 20% rbSt at very low water content ( or = 30% rbSt in nonisothermal conditions. Plasticization by water decreased both T(g) and T(c) quite similarly but didn't impact the noted effect of protein on T(c). Induction time for sucrose crystallization (i.e. nucleation) at approximately 45% RH (23 degrees C) increased almost 10-fold by addition of 10% rbSt, whereas rates of water loss due to crystallization decreased by no more than 2-3-fold. The overall results strongly indicate that formulations of higher protein concentration will be more resistant to sucrose crystallization and thus more robust when transiently exposed to storage temperatures above their T(g).

  13. Clinical application of radiation sterilized demineralized freeze dried bone allograft (DFDBA) and DFDBA combined with bovine periosteum membrane in periodontal defects

    International Nuclear Information System (INIS)

    Tantin R Dwijartini; Paramita Pandansari; Basril Abbas; Nazly Hilmy

    2008-01-01

    Full text: The objective of this report is to evaluate the effects of Radiation Sterilized Demineralized Freeze Dried Bone Allograft (DFDBA) and DFDBA combined with Bovine Periosteum Membrane (BPM) as well as BPM only in some cases of Periodontal Defects. BPM was used as a guided tissue regeneration. This study was carried out to 26 patients as follows : 10 cases for periodontal pocket using only DFDBA and DFDBA combined with BPM for 16 cases which consist of 10 cases of post extraction socket, 5 cases of gingival recession and one case of maxillary bone defect. DFDBA and periosteum membrane used were produced by BATAN Research Tissue Bank. Flap operation was done for all of the treatments, and followed by filling with DFDBA and/or DFDBA combined with periosteum membrane or BPM only. Evaluations were done up to 6 months. Parameters observed were the improvement of bone level, clinical attachment level, pocket depth and gingival margin location as well as increasing the thickness of maxillary bone. All of those evaluations were done by clinical observation and x-ray examination. Results obtained show that the improvement of clinical attachment level, reduces the pocket depth and increases bone density happened in all cases observed. It was also shows that BPM can be used as a guided tissue regeneration. No rejection could be observed in all of those cases. This study clearly indicated that DFDBA had an inductive effect on the formation of new bone and connective tissue. It can be concluded that DFDBA and Bovine Periosteum Membrane are promising to be used in treatment of the case of Periodontal Defects. (Author)

  14. Microbial diversity of a Camembert-type cheese using freeze-dried Tibetan kefir coculture as starter culture by culture-dependent and culture-independent methods.

    Directory of Open Access Journals (Sweden)

    Jun Mei

    Full Text Available The biochemical changes occurring during cheese ripening are directly and indirectly dependent on the microbial associations of starter cultures. Freeze-dried Tibetan kefir coculture was used as a starter culture in the Camembert-type cheese production for the first time. Therefore, it's necessary to elucidate the stability, organization and identification of the dominant microbiota presented in the cheese. Bacteria and yeasts were subjected to culture-dependent on selective media and culture-independent polymerase chain reaction (PCR-denaturing gradient gel electrophoresis (DGGE analysis and sequencing of dominant bands to assess the microbial structure and dynamics through ripening. In further studies, kefir grains were observed using scanning electron microscopy (SEM methods. A total of 147 bacteria and 129 yeasts were obtained from the cheese during ripening. Lactobacillus paracasei represents the most commonly identified lactic acid bacteria isolates, with 59 of a total of 147 isolates, followed by Lactococcus lactis (29 isolates. Meanwhile, Kazachstania servazzii (51 isolates represented the mainly identified yeast isolate, followed by Saccharomyces cerevisiae (40 isolates. However, some lactic acid bacteria detected by sequence analysis of DGGE bands were not recovered by plating. The yeast S. cerevisiae and K. servazzii are described for the first time with kefir starter culture. SEM showed that the microbiota were dominated by a variety of lactobacilli (long and curved cells growing in close association with a few yeasts in the inner portion of the grain and the short lactobacilli were observed along with yeast cells on the exterior portion. Results indicated that conventional culture method and PCR-DGGE should be combined to describe in maximal detail the microbiological composition in the cheese during ripening. The data could help in the selection of appropriate commercial starters for Camembert-type cheese.

  15. Implications of modifying membrane fatty acid composition on membrane oxidation, integrity, and storage viability of freeze-dried probiotic, Lactobacillus acidophilus La-5.

    Science.gov (United States)

    Hansen, Marie-Louise R W; Petersen, Mikael A; Risbo, Jens; Hümmer, Magdalena; Clausen, Anders

    2015-01-01

    The aim of this study was to investigate the effect of altering the fatty acid profile of the lipid membrane on storage survival of freeze-dried probiotic, Lactobacillus acidophilus La-5, as well as study the membrane integrity and lipid oxidation. The fatty acid composition of the lipid membrane of L. acidophilus La-5 was significantly different upon growth in MRS (containing Tween 80, an oleic acid source), or in MRS with Tween 20 (containing C12:0 and C14:0), linoleic, or linolenic acid supplemented. Bacteria grown in MRS showed the highest storage survival rates. No indications of loss of membrane integrity could be found, and membrane integrity could therefore not be connected with loss of viability. Survival of bacteria grown with linoleic or linolenic acid was more negatively affected by the presence of oxygen, than bacteria grown in MRS or with Tween 20 supplemented. A small, but significant, loss of linolenic acid during storage could be identified, and an increase of volatile secondary oxidation products during storage was found for bacteria grown in MRS, or with linoleic, or linolenic acid supplemented, but not for bacteria grown with Tween 20. Overall, the results indicate that lipid oxidation and loss of membrane integrity are not the only or most important detrimental reactions which can occur during storage. By altering the fatty acid composition, it was also found that properties of oleic acid gave rise to more robust bacteria than more saturated or unsaturated fatty acids did. © 2015 American Institute of Chemical Engineers.

  16. Effect of glass-forming biopreservatives on head group rotational dynamics in freeze-dried phospholipid bilayers: A 31P NMR study

    Science.gov (United States)

    Jain, P.; Sen, S.; Risbud, S. H.

    2009-07-01

    P31 NMR spectroscopy has been used to elucidate the role of glass-forming sugars in the preservation of dipalmitoylphosphatidylcholine (DPPC) lipid bilayers. P31 wideline NMR spectra of freeze-dried pure DPPC, DPPC/trehalose, DPPC/glucose, and DPPC/hydroxyethyl starch (HES) mixtures collected in the temperature range of 25-80 °C have been simulated to obtain quantitative information about rotational dynamics and orientation of the lipid head groups in these media. In the case of pure DPPC, DPPC/glucose, and DPPC/HES, the gel-to-liquid crystalline phase transition of DPPC bilayer is characterized by a sudden increase in the rate of rotational diffusion of the PO4 head groups near 40 °C. The corresponding rotational jump frequency increases from a few kilohertz in the gel phase to at least several megahertz in the liquid crystalline phase. On the other hand, in the case of DPPC/trehalose mixture the temperature of this onset of rapid head group dynamics is increased by ˜10 °C. Trehalose reduces the lipid head group motions most effectively in the temperature range of T ≤50 °C relevant for biopreservation. Additionally, and possibly more importantly, trehalose is found to strongly restrict any change in the orientation of the diffusion axis of the PO4 head groups during the phase transformation. This unique ability of trehalose to maintain the dynamical and orientational rigidity of lipid head groups is likely to be responsible for its superior ability in biopreservation.

  17. A comparision of two types of decalcified freeze-dried bone allograft in treatment of dehiscence defects around implants in dogs

    Directory of Open Access Journals (Sweden)

    Ahmad Moghareh Abed

    2011-01-01

    Full Text Available Background: Decalcified freeze-dried bone allograft (DFDBA may have the potential to enhance bone formation around dental implants. Our aim in this study was the evaluation and comparison of two types of DFDBA in treatment of dehiscence defects around Euroteknika® implants in dogs. Methods : In this prospective clinical trial animal study, all mandibular premolars of three Iranian dogs were extracted. After 3 months of healing, fifteen SLA type Euroteknika® dental implants (Natea with 4.1mm diameter and 10mm length were placed in osteotomy sites with dehiscence defects of 5mm length, 4 mm width, and 3mm depth. Guided bone regeneration (GBR procedures were performed using Cenobone and collagen membrane for six implants, the other six implants received Dembone and collagen membrane and the final three implants received only collagen membrane. All implants were submerged. After 4 months of healing, implants were uncovered and stability (Implant Stability Quotient of all implants was measured. Then, block biopsies of each implant site were taken and processed for ground sectioning and histomorphometric analysis. The data was analyzed by ANOVA and Pearson tests. P value less than 0.05 was considered to be significant. Results: All implants osseointegrated after 4 months. The mean values of bone to implant contact for histomorphometric measurements of Cenobone, Denobone, and control groups were 77.36 ± 9.96%, 78.91 ± 11.9% and 71.56 ± 5.61% respectively, with no significant differences among the various treatment groups. The correlation of Implant Stability Quotient and histomorphometric techniques was 0.692. Conclusion: In treating of dehiscence defects with GBR technique in this study, adding DFDBA did not significantly enhance the percentages of bone-to-implant contact measurements; and Implant Stability Quotient Resonance Frequency Analysis appeared to be a precise technique.

  18. Comparison of spray freeze drying and the solvent evaporation method for preparing solid dispersions of baicalein with Pluronic F68 to improve dissolution and oral bioavailability.

    Science.gov (United States)

    He, Xiuqiong; Pei, Lixia; Tong, Henry H Y; Zheng, Ying

    2011-03-01

    The objective of this study was to prepare solid dispersions consisting of baicalein and a carrier with a low glass transition/melting point (Pluronic F68) by spray freeze drying (SFD). We compared these powders to those produced from the conventional solvent evaporation method. In the SFD process, a feeding solution was atomized above the surface of liquid nitrogen following lyophilization, which resulted in instantaneously frozen microparticles. However, solid dispersions prepared by the solvent evaporation method formed a sticky layer on the glass flask with crystalline baicalein separated out from the carrier. The powder samples were characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), surface area measurement, differential scanning calorimetry, and Fourier transform infrared spectrometry. SEM and PXRD results suggested that the majority of baicalein in the SFD-processed solid dispersion was in the amorphous state, which has a higher specific surface area than pure baicalein. However, the majority of baicalein was recrystallized in the solid dispersion at the same composition prepared by the solvent evaporation method, which showed a similar dissolution rate to the physical mixture. SFD product was physically and chemically stable after being stored at 40 °C with low humidity for 6 months. After enzyme hydrolysis, baicalein in the SFD product displayed a significantly shorter T (max) and higher C (max) than pure baicalein after oral dosing. The relative bioavailability of the SFD product versus pure baicalein determined by comparing the AUC(0-12) was 233%, which demonstrated the significantly improved oral bioavailability of baicalein produced by the SFD technique. © 2010 American Association of Pharmaceutical Scientists

  19. FREEZE DRYING PROCESS: A REVIEW

    OpenAIRE

    Soham Shukla

    2011-01-01

    Among the various methods of drying, this article has mentioned only one most important method, “Freeze drying”. This method is mainly used for the drying of thermo labile materials. This method works on the principle of sublimation. This method is divided into 3 steps for its better understanding; these are Freezing, Primary drying, and secondary drying. There are many advantages and disadvantages of this method, but still this is the most useful drying method nowadays.

  20. Al2O3 Coated Concentration-Gradient Li[Ni0.73Co0.12Mn0.15]O2 Cathode Material by Freeze Drying for Long-Life Lithium Ion Batteries

    International Nuclear Information System (INIS)

    Wang, Jingpeng; Du, Chunyu; Yan, Chunqiu; He, Xiaoshu; Song, Bai; Yin, Geping; Zuo, Pengjian; Cheng, Xinqun

    2015-01-01

    Highlights: • Al 2 O 3 -coated concentration-gradient oxide is synthesized by a freeze drying method. • The effect of Al 2 O 3 -coating on concentration-gradient cathode is firstly studied. • Al 2 O 3 -coated sample exhibits high capacity and significantly enhanced cyclability. • Improved cyclability is ascribed to the effective protection of uniform Al 2 O 3 layer. - Abstract: In order to enhance the electrochemical performance of the high capacity layered oxide cathode with a Ni-rich core and a concentration-gradient shell (NRC-CGS), we use a freeze drying method to coat Al 2 O 3 layer onto the surface of NRC-CGS Li[Ni 0.73 Co 0.12 Mn 0.15 ]O 2 material. The samples are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, charge-discharge measurements and electrochemical impedance spectroscopy. It is revealed that an amorphous Al 2 O 3 layer of about 5 nm in thickness is uniformly formed on the surface of NRC-CGS Li[Ni 0.73 Co 0.12 Mn 0.15 ]O 2 material by the freeze drying procedure. The freeze drying Al 2 O 3 -coated (FD-Al 2 O 3 -coated) sample demonstrates similar discharge capacity and significantly enhanced cycling performances, in comparison to the pristine and conventional heating drying Al 2 O 3 -coated (HD-Al 2 O 3 -coated) samples. The capacity decay rate of FD-Al 2 O 3 -coated Li[Ni 0.73 Co 0.12 Mn 0.15 ]O 2 material is 1.7% after 150 cycles at 55 °C, which is 9 and 12 times lower than that of the pristine and HD-Al 2 O 3 -coated samples. The superior electrochemical stability of the FD-Al 2 O 3 -coated sample is attributed to the synergistic protection of CGS and high-quality Al 2 O 3 coating that effectively protect the active material from electrolyte attack. The freeze drying process provides an effective method to prepare the high performance surface-coated electrode materials

  1. Formulation and evaluation of freeze-dried DOTMP kit for the preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP at the hospital radiopharmacy

    Energy Technology Data Exchange (ETDEWEB)

    Das, Tapas; Banerjee, Sharmila [Bhabha Atomic Research Centre, Radiopharmaceuticals Chemistry Section, Mumbai (India); Chakraborty, Sudipta [Bhabha Atomic Research Centre, Isotope Production and Applications Div., Mumbai (India); Sarma, Haladhar D. [Bhabha Atomic Research Centre, Radiation Biology and Health Sciences Div., Mumbai (India)

    2015-07-01

    The objective of the present work is to develop and evaluate freeze-dried DOTMP kit, which could be utilized for the convenient and single-step preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP, both of which have shown potential as alternative agents for metastatic bone pain palliation. Freeze-dried DOTMP kits, each comprising a lyophilized mixture of 20 mg DOTMP and 8.75 mg NaOH, were prepared. The kits were used for the preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP complexes. The agents were prepared by dissolving the lyophilized powder in 1 mL of normal saline and incubating with {sup 177}LuCl{sub 3} or {sup 153}SmCl{sub 3}, produced in-house, for 15 min at room temperature. Pharmacokinetic behavior and biological distribution of the agents were studied by carrying out biodistribution as well as scintigraphic studies in normal male Wistar rats. Shelf-life of the freeze-dried kits was also ascertained. Clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP complexes, comprising up to 3.7 GBq (100 mCi) of activity, were prepared with > 99% radiochemical purity using the freeze-dried kits. The complexes exhibited high in vitro stability when stored at room temperature. Biological studies showed selective skeletal accumulation and insignificant uptake of the radiotracers in any of the vital organs/tissue. The non-accumulated activity exhibited primary urinary clearance. The kits had a shelf-life of 2 years when stored at 4 C temperature. Freeze-dried DOTMP kits, suitable for the preparation of clinical-scale {sup 177}Lu-DOTMP and {sup 153}Sm-DOTMP, have been developed and the radiochemical and biological behaviors of the radiolabeled agents have been studied. The use of the kit at the hospital radiopharmacy is expected to make the preparations easy and convenient. This in turn will enable the widespread dissemination of these promising agents towards their application for regular use.

  2. Effect of Chronic Alcohol Consumption on Phosphatidylcholine ...

    African Journals Online (AJOL)

    Purpose: To investigate the correlation between alcohol-induced oxidative stress and tissue phosphatidylcholine hydroperoxide (PC-OOH) content of rat liver and brain. Methods: Ten Wistar rats were divided into two groups: one group was given 20 % ethanol (5 g/kg) and the other the same volume of normal saline, orally ...

  3. PENGGUNAAN BERBAGAI JENIS BAHAN PELINDUNG UNTUK MEMPERTAHANKAN VIABILITAS BAKTERI ASAM LAKTAT YANG DI ISOLASI DARI AIR SUSU IBU PADA PROSES PENGERINGAN BEKU [Utilization of various cryogenic agents during freeze drying to Maintain the viability of Lactic Acid Bacteria Isolated from breast milk

    Directory of Open Access Journals (Sweden)

    Ni Nyoman Puspawati1*

    2010-06-01

    Full Text Available Lactic acid bacteria are the most important bacteria having potential as probiotic. The objectives of the present study were to examine the growth of Lactic Acid Bacteria, identify the Lactic Acid Bacteria capable of surviving and evaluate the best cryogenic agents that protect the viability of Lactic Acid Bacteria during freeze drying. Four cryogenic agents, i.e. sucrose, lactose, skim milk and maltodextrin, were used in freeze drying of three species of Lactic Acid Bacteria, i.e. Pediococcus pentosaceus A16, Lactobacillus brevis A17 and Lactobacillus rhamnosus R21 isolated from breast milk. Evaluation included viability before and after freeze drying, survival of freeze dried culture in 0.5 % bile salt and low pH for 5 hours. The result showed that three of cryogenics, i.e. sucrose, lactose and skim milk improved the viability of freeze dried of all lactobacilli, except maltodextrin that did not give protection to L. rhamnosus R21. Evaluation on the survival of LAB in 0.5 % bile salt showed that cryogenic agents improved the survival rate of all Lactic Acid Bacteria during freeze drying. The cryogenic also improved the survival rate of LAB at low pH, with the best protection given by skim milk on L. rhamnosus R21.

  4. Comparative evaluation of platelet-rich fibrin with demineralized freeze-dried bone allograft in periodontal infrabony defects: A randomized controlled clinical study

    Directory of Open Access Journals (Sweden)

    Monali Shah

    2015-01-01

    Full Text Available Introduction: Several bone graft materials have been used in the treatment of infrabony defects. Demineralized freeze-dried bone allograft (DFDBA has been histologically proven to be the material of choice for regeneration. However, platelet-rich fibrin (PRF has been said to have several properties that aid in healing and regeneration. Hence, this study focuses on the regenerative capacity of PRF when compared with DFDBA. Materials and Methods: A total of 40 sites with intrabony defects were selected and were assigned to the test group (open flap debridement [OFD] and PRF, n = 20 and the control group (OFD + DFDBA, n = 20. At the test sites, two PRF plugs were placed in the intrabony defect after debridement of the site and flap was sutured in place. The parameters measured were probing depth (PD, relative attachment level (RAL, and gingival marginal level (GML. These parameters were measured just before surgery (baseline and at 6 months postsurgery. The changes in PD, RAL, and GML were analyzed at baseline and postsurgically after 6 months in each group with paired t-test and between the two groups with unpaired t-test. Results: The mean reduction in PD after 6 months in the test PRF group is 3.67 ± 1.48 mm where in control DFDBA group is 3.70 ± 1.78 mm. Gain in RAL in the test PRF group is 2.97 ± 1.42 mm where in control DFDBA group, it is 2.97 ± 1.54 mm. Gingival margin migrated apically in the test PRF group by 0.43 ± 1.31 mm where in control DFDBA group by 0.72 ± 2.3 mm. It was seen that the differences in terms of PD (P = 0.96, RAL (P = 1.00 and GML (P = 0.62 were not significant. Conclusion: Platelet-rich fibrin has shown significant results after 6 months, which is comparable to DFDBA for periodontal regeneration in terms of clinical parameters. Hence, it can be used in the treatment of intrabony defects.

  5. Rapid diagnosis of avian influenza virus in wild birds: use of a portable rRT-PCR and freeze-dried reagents in the field.

    Science.gov (United States)

    Takekawa, John Y; Hill, Nichola J; Schultz, Annie K; Iverson, Samuel A; Cardona, Carol J; Boyce, Walter M; Dudley, Joseph P

    2011-08-02

    Wild birds have been implicated in the spread of highly pathogenic avian influenza (HPAI) of the H5N1 subtype, prompting surveillance along migratory flyways. Sampling of wild birds for avian influenza virus (AIV) is often conducted in remote regions, but results are often delayed because of the need to transport samples to a laboratory equipped for molecular testing. Real-time reverse transcriptase polymerase chain reaction (rRT-PCR) is a molecular technique that offers one of the most accurate and sensitive methods for diagnosis of AIV. The previously strict lab protocols needed for rRT-PCR are now being adapted for the field. Development of freeze-dried (lyophilized) reagents that do not require cold chain, with sensitivity at the level of wet reagents has brought on-site remote testing to a practical goal. Here we present a method for the rapid diagnosis of AIV in wild birds using an rRT-PCR unit (Ruggedized Advanced Pathogen Identification Device or RAPID, Idaho Technologies, Salt Lake City, UT) that employs lyophilized reagents (Influenza A Target 1 Taqman; ASAY-ASY-0109, Idaho Technologies). The reagents contain all of the necessary components for testing at appropriate concentrations in a single tube: primers, probes, enzymes, buffers and internal positive controls, eliminating errors associated with improper storage or handling of wet reagents. The portable unit performs a screen for Influenza A by targeting the matrix gene and yields results in 2-3 hours. Genetic subtyping is also possible with H5 and H7 primer sets that target the hemagglutinin gene. The system is suitable for use on cloacal and oropharyngeal samples collected from wild birds, as demonstrated here on the migratory shorebird species, the western sandpiper (Calidrus mauri) captured in Northern California. Animal handling followed protocols approved by the Animal Care and Use Committee of the U.S. Geological Survey Western Ecological Research Center and permits of the U.S. Geological Survey

  6. Rapid diagnosis of avian influenza virus in wild birds: Use of a portable rRT-PCR and freeze-dried reagents in the field

    Science.gov (United States)

    Takekawa, John Y.; Hill, N.J.; Schultz, A.K.; Iverson, S.A.; Cardona, C.J.; Boyce, W.M.; Dudley, J.P.

    2011-01-01

    Wild birds have been implicated in the spread of highly pathogenic avian influenza (HPAI) of the H5N1 subtype, prompting surveillance along migratory flyways. Sampling of wild birds for avian influenza virus (AIV) is often conducted in remote regions, but results are often delayed because of the need to transport samples to a laboratory equipped for molecular testing. Real-time reverse transcriptase polymerase chain reaction (rRT-PCR) is a molecular technique that offers one of the most accurate and sensitive methods for diagnosis of AIV. The previously strict lab protocols needed for rRT-PCR are now being adapted for the field. Development of freeze-dried (lyophilized) reagents that do not require cold chain, with sensitivity at the level of wet reagents has brought on-site remote testing to a practical goal. Here we present a method for the rapid diagnosis of AIV in wild birds using an rRT-PCR unit (Ruggedized Advanced Pathogen Identification Device or RAPID, Idaho Technologies, Salt Lake City, UT) that employs lyophilized reagents (Influenza A Target 1 Taqman; ASAY-ASY-0109, Idaho Technologies). The reagents contain all of the necessary components for testing at appropriate concentrations in a single tube: primers, probes, enzymes, buffers and internal positive controls, eliminating errors associated with improper storage or handling of wet reagents. The portable unit performs a screen for Influenza A by targeting the matrix gene and yields results in 2-3 hours. Genetic subtyping is also possible with H5 and H7 primer sets that target the hemagglutinin gene. The system is suitable for use on cloacal and oropharyngeal samples collected from wild birds, as demonstrated here on the migratory shorebird species, the western sandpiper (Calidrus mauri) captured in Northern California. Animal handling followed protocols approved by the Animal Care and Use Committee of the U.S. Geological Survey Western Ecological Research Center and permits of the U.S. Geological Survey

  7. Freeze-dried live attenuated smallpox vaccine prepared in cell culture "LC16-KAKETSUKEN": Post-marketing surveillance study on safety and efficacy compliant with Good Clinical Practice.

    Science.gov (United States)

    Nishiyama, Yasumasa; Fujii, Tatsuya; Kanatani, Yasuhiro; Shinmura, Yasuhiko; Yokote, Hiroyuki; Hashizume, So

    2015-11-09

    In Japan, production of smallpox vaccine LC16m8 (named LC16-KAKETSUKEN) was restarted and was determined to be maintained as a national stockpile in March 2002. To conduct a post-marketing surveillance study of the vaccination of freeze-dried live attenuated smallpox vaccine prepared in cell culture LC16-KAKETSUKEN using attenuated vaccinia strain LC16m8. The study complied with Good Clinical Practice, focusing on a comparison between primary vaccinees and re-vaccinees. 268 personnel (261 males and 7 females) of the Japan Ground Self-Defense Force were inoculated with LC16-KAKETSUKEN and thereafter adverse events and efficacy were evaluated. Among 268 vaccinee participants, the following vaccinees showed adverse events, none serious: 53 of 196 primary vaccinees (without previous smallpox vaccination), 4 of 71 re-vaccinees (with previous smallpox vaccination) and 1 vaccinee with unknown previous vaccination history. A breakdown of adverse events observed in this study (total 268 vaccinees) showed the following minor or mild adverse events: 52 (19.4%) swelling of axillary lymph node, 4 (1.5%) fever, 2 (0.7%) fatigue, 1 (0.4%) of rash, 14 (5.2%) erythema at the inoculation site, 1 (0.4%) swelling at the inoculation site and 1 (0.4%) autoinoculation. The incidence of adverse events for primary vaccinees (53/196; 27.0%) was significantly higher than for re-vaccinees (4/71; 5.6%). However, the proportion of vaccine take was significantly higher for primary vaccinees (185/196; 94.4%) than for re-vaccinees (58/71; 81.7%). Although the proportion of vaccine take of re-vaccinees was significantly lower than for primary vaccinees due to preexisting immunity by previous vaccination, no significant difference was found in neutralizing antibody titers between primary vaccinees and re-vaccinees at 1, 4 and 7 months after LC16-KAKETSUKEN vaccination. The present post-marketing surveillance study compliant with Good Clinical Practice demonstrated the efficacy and safety of the

  8. Histologic and histomorphometric evaluation of bone regeneration using nanocrystalline hydroxyapatite and human freeze-dried bone graft : An experimental study in rabbit.

    Science.gov (United States)

    Sadeghi, Rokhsareh; Najafi, Mohammad; Semyari, Hassan; Mashhadiabbas, Fatemeh

    2017-03-01

    Bone regeneration is an important concern in periodontal treatment and implant dentistry. Different biomaterials and surgical techniques have been used for this purpose. The aim of the present study was to compare the effect of nanocrystalline hydroxyapatite and human freeze-dried bone graft (FDBG) in regeneration of rabbit calvarium bony defects by histologic and histomorphometric evaluation. In this experimental study, three similar defects, measuring 8 mm in diameter, were created in the calvaria of 16 white New Zealand rabbits. Two defects were filled with FDBG and nanocrystalline hydroxyapatite silica gel, while the other one remained unfilled to be considered as control. All the defects were covered with collagen membranes. During the healing period, two animals perished; so 14 rabbits were divided into two groups: half of them were euthanized after 6 weeks of healing and the other half after 12 weeks. The specimens were subjected to histologic and histomorphometric examinations for assessment of the following variables: percentage of bone formation and residual graft material, inflammation scores, patterns of bone formation and type of newly formed bone. The percentages of new bone formation after 6 weeks were 14.22 ± 7.85, 21.57 ± 6.91, and 20.54 ± 10.07% in FDBG, NanoBone, and control defects. These values were 27.54 ± 20.19, 23.86 ± 6.27, and 26.48 ± 14.18% in 12-week specimens, respectively. No significant differences were found in the amount of bone formation between the groups. With regard to inflammation, the control and NanoBone groups showed significantly less inflammation compared to FDBG at the 6-week healing phase (P = 0.04); this difference was not significant in the 12-week specimens. Based on the results of this experimental study, both NanoBone and FDBG exhibited a similar effect on bone formation.

  9. Volumetric and viscometric behaviour of soya bean and gram ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-06-17

    Jun 17, 2008 ... properties. Thus an estimation of intermolecular forces with water and proteins in aqueous solution is of interest to protein engineering (Mulder et al., 1839; Leiberg et al.,. 1841). Soya protein has cholesterol lowering effect in human serum (Carroll et al., 1995, 1980) with lysine and arginine rich soya protein ...

  10. Effect of soya bean diet preparations on some haematological and ...

    African Journals Online (AJOL)

    Effects of Soya bean diet preparations on the hematocrit, hemoglobin concentration, total plasma protein, plasma albumin, sodium, potassium and chloride concentrations were studied in male albino rats. The animals were fed diets containing 75%, 50% and 25% Soya bean in groups II, III and IV respectively. Group I rats ...

  11. Volumetric and viscometric behaviour of soya bean and gram ...

    African Journals Online (AJOL)

    Volumetric and viscometric behaviour of soya bean and gram proteins in aqueous methotrexate (anticancer drug) solution at 298.15 to 308.15K. ... and viscosities (h) for 0.00005 to 0.0004 kg.mol-1 (50 to 400 mmol kg-1) aqueous methotrexate (MTX), gram (Gp) and soya bean (SBp) proteins, and similar compositions of Gp

  12. Utilization of soya protein as an alternative protein source in ...

    African Journals Online (AJOL)

    The effect of replacing fish protein with soya protein in tilapia (Oreochromis niloticus) diets was examined. Three isoproteic (35%) diets containing 0% (FD); 50% (MD) and 100% (SD) fish protein substituted by soya protein were formulated. Fish (initial weight = 11.56 ± 4.22 g) was fed with experimental diets for 180 days.

  13. Soya ve Soya Ürünlerinin Fonksiyonel Gıda Bileşenleri

    Directory of Open Access Journals (Sweden)

    Dilara Nilüfer

    2015-02-01

    Full Text Available Soya ürünleri, yüksek miktarda soya proteini, izoflavonlar, omega–3-yağ asitleri ve diyet lifi içerikleri ile çok önemli fonksiyonel gıda bileşenleri veya ürünleridir. Sağlığa olumlu etkilerinden dolayı, ürün geliştirmede soyanın geleneksel gıdalara tamamen veya kısmen ilave edilmesi veya diğer bileşenlerle yer değiştirmesi yönünde eğilimler giderek artış göstermektedir. Soyanın sağlığa yararlı etkileri tüketicilere yaygın olarak tüketilen ve kabul edilebilir nitelikteki soya ürünleri ile ulaştırılabilir. Çok çeşitli soya esaslı bileşen dünya pazarında mevcut olup, formülasyonların optimizasyonu için her birinin fonksiyonu, besin değeri, maliyet ve lezzet özellikleri tam olarak anlaşılmalıdır. Bu çalışmada; soya ürünlerinin fonksiyonel gıda bileşenlerinin sağlığa olan etkileri, gıda süreçlerinden etkilenmeleri ve ürünlerde uygulamalarının irdelenmesi amaçlanmıştır.

  14. Effect of fermented soya beans on diarrhoea and feed efficiency in weaned piglets

    NARCIS (Netherlands)

    Kiers, J.L.; Meijer, J.C.; Nout, M.J.R.; Rombouts, F.M.; Nabuurs, M.J.A.; Meulen, van der J.

    2003-01-01

    Aims: To evaluate anti-diarrhoeal and growth enhancing properties of fermented soya beans in weaned piglets. Methods and Results: In a first phase piglet diet, toasted full-fat soya beans (20%) were replaced with either cooked soya beans or Rhizopus microsporus or Bacillus subtilis fermented soya

  15. [Soya isoflavones and evidences on cardiovascular protection].

    Science.gov (United States)

    González Cañete, Natalia; Durán Agüero, Samuel

    2014-06-01

    Soya isoflavones represent a group of non-nutritive, bioactive compounds, of non-steroidal phenolic nature that are present in soy bean and derived foods. They share with other compounds the capacity of binding to estrogenic receptors from different cells and tissues so that they may act as phytoestrogens. The current interest in these compounds comes from the knowledge that in Asian populations with high levels of their consumption the prevalence of cancer and cardiovascular disease is lower, as compared to the Western countries populations. This cardiovascular benefit would be the result not only of the modulation of plasma lipids, which is a widely studied mechanism. This paper reviews the published evidence about the beneficial effects of soya isoflavones and the different mechanisms of action that would benefit cardiovascular health and that surpass the mechanisms traditionally approached such as the modulation of plasma lipids, and that implicate the regulation of cellular and enzymatic functions in situations such as inflammation, thrombosis, and atherosclerotic progression. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  16. Inflammatory markers in a randomised soya intervention among men.

    Science.gov (United States)

    Maskarinec, Gertraud; Oum, Robert; Chaptman, Ann K; Ognjanovic, Simona

    2009-06-01

    The present analysis investigated the effect of soya foods on serum levels of six inflammatory markers, leptin, adiponectin, monocyte attractant protein 1 (MCP-1), macrophage inflammatory protein-1b (MIP-1b), IL-6 and C-reactive protein (CRP), and their relationship with BMI and lifetime soya intake. We randomised twenty-four men to a high- (two daily servings with 30-35 mg isoflavones per serving) or a low-soya diet for 3 months. After a 1-month washout period, the men crossed over to the other treatment. We used a multiplex bead immunoassay to measure leptin, adiponectin, MCP-1 and MIP-1b and ELISA assays for IL-6 and CRP. The statistical analysis applied mixed models that incorporated the four repeated measurements. The men had a mean age of 58.7 (sd 7.2) years and a mean BMI of 28.4 (sd 4.9) kg/m2. We observed no significant intervention effect of the soya treatment on any of the six markers. After adjustment for age and ethnicity, highly significant associations of BMI and body weight with leptin and MCP-1 emerged. Men with high soya intake early in life also had higher levels of leptin and MCP-1, whereas no association was seen for soya intake during adulthood. MIP-1b, adiponectin, IL-6 and CRP were not related to BMI, body weight or soya intake at any time in life. No intervention effect of soya foods on markers of inflammation was observed in this small study, but adiposity and early-life soya intake were related to higher leptin and MCP-1 levels.

  17. Freeze-drying synthesis of three-dimensional porous LiFePO{sub 4} modified with well-dispersed nitrogen-doped carbon nanotubes for high-performance lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Xiaofeng; Zhou, Yingke, E-mail: zhouyk888@hotmail.com; Song, Yijie

    2017-04-01

    Highlights: • Three-dimensional porous LiFePO{sub 4}/N-CNTs is synthesized by a freeze-drying method. • The N-CNTs conductive network enhances the electron transport within the LiFePO{sub 4} electrode. • The continuous pores accelerate the diffusion of lithium ions. • LiFePO{sub 4}/N-CNTs demonstrates an excellent electrochemical Li-insertion performance. - Abstract: The three-dimensional porous LiFePO{sub 4} modified with uniformly dispersed nitrogen-doped carbon nanotubes has been successfully prepared by a freeze-drying method. The morphology and structure of the porous composites are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), and the electrochemical performances are evaluated using the constant current charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy. The nitrogen-doped carbon nanotubes are uniformly dispersed inside the porous LiFePO{sub 4} to construct a superior three-dimensional conductive network, which remarkably increases the electronic conductivity and accelerates the diffusion of lithium ion. The porous composite displays high specific capacity, good rate capability and excellent cycling stability, rendering it a promising positive electrode material for high-performance lithium-ion batteries.

  18. Effect of freeze-drying and self-ignition process on the microstructural and electrochemical properties of Li{sub 4}Ti{sub 5}O{sub 12}

    Energy Technology Data Exchange (ETDEWEB)

    Jamin, Claire [GREEnMat/LCIS, Department of Chemistry, B6a, University of Liège, Sart-Tilman, 4000 Liège (Belgium); Traina, Karl [GREEnMat/LCIS, Department of Chemistry, B6a, University of Liège, Sart-Tilman, 4000 Liège (Belgium); APTIS, Department of Physics, B5a, University of Liège, Sart-Tilman, 4000 Liège (Belgium); Eskenazi, David [Chemical Engineering Laboratory, Department of Applied Chemistry, B6a, University of Liège, Sart-Tilman, 4000 Liège (Belgium); Krins, Natacha; Cloots, Rudi; Vertruyen, Bénédicte [GREEnMat/LCIS, Department of Chemistry, B6a, University of Liège, Sart-Tilman, 4000 Liège (Belgium); Boschini, Frédéric, E-mail: frederic.boschini@ulg.ac.be [GREEnMat/LCIS, Department of Chemistry, B6a, University of Liège, Sart-Tilman, 4000 Liège (Belgium); APTIS, Department of Physics, B5a, University of Liège, Sart-Tilman, 4000 Liège (Belgium)

    2013-11-15

    Graphical abstract: - Highlights: • Li{sub 4}Ti{sub 5}O{sub 12} is prepared by a method involving self-ignition of a freeze-dried gel. • Addition of NH{sub 4}NO{sub 3} modifies the self-ignition propagation mode. • Well-crystallized Li{sub 4}Ti{sub 5}O{sub 12} phase is obtained after only 2 h at 800 °C. • Li{sub 4}Ti{sub 5}O{sub 12} powder has 161 mAh g{sup −1} capacity and good retention at C/4 rate. - Abstract: Crystalline Li{sub 4}Ti{sub 5}O{sub 12} is synthesized by a method involving the freeze-drying and self-ignition of a gel prepared from titanium isopropoxide, lithium nitrate and hydroxypropylmethylcellulose (HPMC). This synthesis route yields crystalline Li{sub 4}Ti{sub 5}O{sub 12} particles after calcination at 800 °C for 2 h. In an alternative route, addition of ammonium nitrate shifts the self-ignition mode from wave-like propagation to simultaneous. Powders with different microstructures are thereby obtained. Electrochemical characterization shows that the best results for Li{sup +} intercalation/desintercalation are obtained for the powder prepared without ammonium nitrate addition. These results highlight the necessity for a control of the self-ignition mode to obtain adequate properties.

  19. Freeze-drying synthesis of three-dimensional porous LiFePO4 modified with well-dispersed nitrogen-doped carbon nanotubes for high-performance lithium-ion batteries

    International Nuclear Information System (INIS)

    Tu, Xiaofeng; Zhou, Yingke; Song, Yijie

    2017-01-01

    Highlights: • Three-dimensional porous LiFePO 4 /N-CNTs is synthesized by a freeze-drying method. • The N-CNTs conductive network enhances the electron transport within the LiFePO 4 electrode. • The continuous pores accelerate the diffusion of lithium ions. • LiFePO 4 /N-CNTs demonstrates an excellent electrochemical Li-insertion performance. - Abstract: The three-dimensional porous LiFePO 4 modified with uniformly dispersed nitrogen-doped carbon nanotubes has been successfully prepared by a freeze-drying method. The morphology and structure of the porous composites are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), and the electrochemical performances are evaluated using the constant current charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy. The nitrogen-doped carbon nanotubes are uniformly dispersed inside the porous LiFePO 4 to construct a superior three-dimensional conductive network, which remarkably increases the electronic conductivity and accelerates the diffusion of lithium ion. The porous composite displays high specific capacity, good rate capability and excellent cycling stability, rendering it a promising positive electrode material for high-performance lithium-ion batteries.

  20. Ca2+-induced isotropic motion and phosphatidylcholine flip-flop in phosphatidylcholine-cardiolipin bilayers

    NARCIS (Netherlands)

    Gerritsen, W.J.; Kruijff, B. de; Verkleij, A.J.; Gier, J. de; Deenen, L.L.M. van

    1980-01-01

    Ca2+ induces a structural change in phosphatidylcholine-cardiolipin bilayers, which is visualised by freeze-fracturing as lipidic particles associated with the bilayer and is detected by 31P-NMR as isotropic motion of the phospholipids. In this structure a rapid transbilayer movement of

  1. Phospholipid lateral diffusion in phosphatidylcholine-sphingomyelin-cholesterol monolayers; Effects of oxidatively truncated phosphatidylcholines

    Czech Academy of Sciences Publication Activity Database

    Parkkila, P.; Štefl, Martin; Olžyńska, Agnieszka; Hof, Martin; Kinnunen, P. K. J.

    2015-01-01

    Roč. 1848, č. 1 (2015), s. 167-173 ISSN 0005-2736 R&D Projects: GA ČR GBP208/12/G016 Institutional support: RVO:61388955 Keywords : Oxidatively truncated phosphatidylcholines * Lateral diffusion * Fluorescence correlation spectroscopy Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.687, year: 2015

  2. Improving oxidative stability of soya and sunflower oil using ...

    African Journals Online (AJOL)

    Rosmarinus officinallis) and tert- butyl-hydroquinone (TBHQ) as possible antioxidants in sunflower and soya oil. Upon addition of 200 ppm of dried leaf extract, acetone extract yielded protection of the samples against oxidation more efficiently as ...

  3. Preparation and characterization of soaps made from soya bean oil ...

    African Journals Online (AJOL)

    This research work deals with the preparation of soaps from neem oil and soya bean oil blends and analyses the soap produced. The soaps were produced using cold process technique by varying the percentage of oils; (soya bean oil and neem oil) in the ratio of 100%, 90/10%, 80/20%, 70/30%, 60/40%, 50/50%, 40/60%, ...

  4. Watershed responses to Amazon soya bean cropland expansion and intensification.

    Science.gov (United States)

    Neill, Christopher; Coe, Michael T; Riskin, Shelby H; Krusche, Alex V; Elsenbeer, Helmut; Macedo, Marcia N; McHorney, Richard; Lefebvre, Paul; Davidson, Eric A; Scheffler, Raphael; Figueira, Adelaine Michela e Silva; Porder, Stephen; Deegan, Linda A

    2013-06-05

    The expansion and intensification of soya bean agriculture in southeastern Amazonia can alter watershed hydrology and biogeochemistry by changing the land cover, water balance and nutrient inputs. Several new insights on the responses of watershed hydrology and biogeochemistry to deforestation in Mato Grosso have emerged from recent intensive field campaigns in this region. Because of reduced evapotranspiration, total water export increases threefold to fourfold in soya bean watersheds compared with forest. However, the deep and highly permeable soils on the broad plateaus on which much of the soya bean cultivation has expanded buffer small soya bean watersheds against increased stormflows. Concentrations of nitrate and phosphate do not differ between forest or soya bean watersheds because fixation of phosphorus fertilizer by iron and aluminium oxides and anion exchange of nitrate in deep soils restrict nutrient movement. Despite resistance to biogeochemical change, streams in soya bean watersheds have higher temperatures caused by impoundments and reduction of bordering riparian forest. In larger rivers, increased water flow, current velocities and sediment flux following deforestation can reshape stream morphology, suggesting that cumulative impacts of deforestation in small watersheds will occur at larger scales.

  5. Quantifying Dustiness, Specific Allergens, and Endotoxin in Bulk Soya Imports

    Directory of Open Access Journals (Sweden)

    Howard J. Mason

    2017-11-01

    Full Text Available Soya is an important bulk agricultural product often transported by sea as chipped beans and/or the bean husks after pelletisation. There are proven allergens in both forms. Bulk handling of soya imports can generate air pollution containing dust, allergens, and pyrogens, posing health risks to dockside workers and surrounding populations. Using an International Organization for Standardization (ISO standardised rotating drum dustiness test in seven imported soya bulks, we compared the generated levels of dust and two major soya allergens in three particle sizes related to respiratory health. Extractable levels of allergen and endotoxin from the bulks showed 30–60 fold differences, with levels of one allergen (hydrophobic seed protein and endotoxin higher in husk. The generated levels of dust and allergens in the three particle sizes also showed very wide variations between bulks, with aerolysed levels of allergen influenced by both the inherent dustiness and the extractable allergen in each bulk. Percentage allergen aerolysed from pelletized husk—often assumed to be of low dustiness—after transportation was not lower than that from chipped beans. Thus, not all soya bulks pose the same inhalation health risk and reinforces the importance of controlling dust generation from handling all soya bulk to as low as reasonably practicable.

  6. Soya Fasulyesinden Konsantre Protein Üretimi ve Soya Ürünlerinin Bileşim Unsurları

    OpenAIRE

    Artık, Nevzat

    2014-01-01

    Soya fasulyesi üretimi ülkemizde 1981 verilerine göre 15000 ton düzeyindedir. Ortalama verim 88 kg da olarak gerçekleşmektedir. Ülkemizde üretilen soya fasulyesinin büyük bir çoğunluğu hayvan yemi olarak kullanılmaktadır. Bileşimi çok zengin olan ve hayvansal proteine eşdeğer oranda protein içeren soya fasulyesi gereğince değerlendirilememektedir. Soya fasulyesinden proteince zengin değişik ürünler elde edilmektedir. Bunlar soya unu, konsantre soya proteini, soya izolatı, et analogu ve ferme...

  7. Eletrólise de resíduos poluidores: I - Efluente de uma indústria liofilizadora de condimentos Electrolysis of polluting wastes: I - Wastewater from a seasoning freeze-drying industry

    Directory of Open Access Journals (Sweden)

    Dejanira F. de Angelis

    1998-02-01

    Full Text Available Wastewater from a seasoning freeze-drying industry was electrolysed to increase its biodegradability. Stainless-steel electrodes were used at 9.09 A/m², for up to 80 min. Conductivity, pH, biochemical (BOD and chemical (COD oxygen demands, Daphnia similis acute toxicity bioassays, and bacteria counting through the plate count agar method were determined after different times of electrolysis. The results (e.g. higher BOD and lower COD showed that the biodegradability of the wastewater was significantly increased; furthermore, Fe2+ ions liberated by the electrodes cause microorganisms to die and, when oxidised to Fe3+, contribute for the flocculation and sedimentation of solid residues.

  8. PENGARUH DEFATTING, FREKUENSI PENCUCIAN DAN JENIS DRYOPROTECTANT TERHADAP MUTU TEPUNG SURIMI IKAN LELE KERING BEKU [Effect of Defatting, Washing Cycle and Dryoprotectant Type on the Quality of Freeze Dried Catfish Surimi Powder

    Directory of Open Access Journals (Sweden)

    Wahyu Ramadhan*

    2014-06-01

    Full Text Available Freeze dried surimi powder is a surimi type processed by freeze drying. To utilize oversized catfish and to reduce surimi handling cost, oversized catfish has been used as raw material of surimi powder. The study aimed to determine the effect of defatting (NaHCO3 concentration and soaking duration, washingcycle,and dryoprotectant type on catfish surimi, as well as quality differences between surimi powder and wet surimi. With regard to defatting step, soaking in NaHCO3 0.75% for 10 minutes was found as the best treatment and resulting in a fat content of 1.52%. Moreover, one time of washing cycle was found as the most appropriate procedure to obtain a superior quality of surimi with whiteness value 57.21%, water holding capacity 73.28%, salts soluble protein 7.17%, pH 6.69, and gel strength 482.3 g/cm2, folding value of 4.84, and teeth cutting value of 8.26. Trehalose 6% was the most suitable dryoprotectant resulting in surimi powder with water holding capacity of 8.01 mL/g, gel strength 826.3 g/cm2, salt soluble protein 18.98%, density 4.06 mL/10 g, rehydration capacity 3.81, emulsion capacity 69.3%, emulsion stability 59.3%, foaming capacity 25.33% and foaming stability 9.40%. The microstructure profile of surimi powder added with trehalose had more compact tissues, without any damage and clots, than that treated with other dryoprotectants. However, surimi powder still had lower protein content than wet surimi, and lower physical and chemical properties, particularly in its teeth cutting and folding characteristics.

  9. Development of new-generation dietary bread technologies by using soya processing products

    Directory of Open Access Journals (Sweden)

    M.A. Silagadze

    2017-06-01

    Full Text Available In order to develop low-calorie high-biological value dietary bread, we used the soya processing products – roasted full fat soya flour, soya milk and soya pomace. There has been studied their chemical and micro nutrient composition. The study shows that the soya processing products have low energy and high biological value, and exhibit low glycemic index that makes them very attractive for the design of dietary food products. In order to increase bioavailability of soya, we carried out its sprouting. We studied the impact of different technological factors on the accumulation dynamics of highly digestible components of soya. based on the studies of the separate and complex influence of the soya processing products on the quality of whole wheat bread, there have been determined the optimal doses of food additives. There has been developed a new-generation dietary product with the trade name “Our Daily Bread”, as well as its making technology.

  10. Surfactant phosphatidylcholine metabolism and surfactant function in preterm, ventilated lambs

    International Nuclear Information System (INIS)

    Jobe, A.H.; Ikegami, M.; Seidner, S.R.; Pettenazzo, A.; Ruffini, L.

    1989-01-01

    Preterm lambs were delivered at 138 days gestational age and ventilated for periods up to 24 h in order to study surfactant metabolism and surfactant function. The surfactant-saturated phosphatidylcholine pool in the alveolar wash was 13 +/- 4 mumol/kg and did not change from 10 min to 24 h after birth. Trace amounts of labeled natural sheep surfactant were mixed with fetal lung fluid at birth. By 24 h, 80% of the label had become lung-tissue-associated, yet there was no loss of label from phosphatidylcholine in the lungs when calculated as the sum of the lung tissue plus alveolar wash. De novo synthesized phosphatidylcholine was labeled with choline given by intravascular injection at 1 h of age. Labeled phosphatidylcholine accumulated in the lung tissue linearly to 24 h, and the labeled phosphatidylcholine moved through lamellar body to alveolar pools. The turnover time for alveolar phosphatidylcholine was estimated to be about 13 h, indicating an active metabolic pool. A less surface-active surfactant fraction recovered as a supernatant after centrifugation of the alveolar washes at 40,000 x g increased from birth to 10 min of ventilation, but no subsequent changes in the distribution of surfactant phosphatidylcholine in surfactant fractions occurred. The results were consistent with recycling pathway(s) that maintained surface-active surfactant pools in preterm ventilated lambs

  11. Grain product of 34 soya mutant lines

    International Nuclear Information System (INIS)

    Salmeron E, J.; Mastache L, A. A.; Valencia E, F.; Diaz V, G. E.; Cervantes S, T.; De la Cruz T, E.; Garcia A, J. M.; Falcon B, T.; Gatica T, M. A.

    2009-01-01

    This work was development with the objective of obtaining information of the agronomic behavior of 34 soya mutant lines (R 4 M 18 ) for human consumption and this way to select the 2 better lines. The genetic materials were obtained starting from the variety ISAAEG-B M2 by means of the application of recurrent radiation with Co 60 gammas, to a dose of 350 Gray for the first two generations and both later to 200 Gray and selection during 17 cycles, being obtained the 34 better lines mutants with agronomic characteristic wanted and good flavor. The obtained results were that the mutant lines L 25 and L 32 produced the major quantity in branches/plant number with 7.5 and 7.25, pods/plant number with 171.25 and 167, grains/plant number with 350.89 and 333.07 and grain product (ton/ha) to 15% of humidity 5.15 and 4.68 ton/ha, respectively. (Author)

  12. The fate of phosphorus fertilizer in Amazon soya bean fields.

    Science.gov (United States)

    Riskin, Shelby H; Porder, Stephen; Neill, Christopher; Figueira, Adelaine Michela e Silva; Tubbesing, Carmen; Mahowald, Natalie

    2013-06-05

    Fertilizer-intensive soya bean agriculture has recently expanded in southeastern Amazonia, and whereas intensive fertilizer use in the temperate zone has led to widespread eutrophication of freshwater ecosystems, the effects in tropical systems are less well understood. We examined the fate of fertilizer phosphorus (P) by comparing P forms and budgets across a chronosequence of soya bean fields (converted to soya beans between 2003 and 2008) and forests on an 800 km(2) soya bean farm in Mato Grosso, Brazil. Soya bean fields were fertilized with 50 kg P ha(-1) yr(-1) (30 kg P ha(-1) yr(-1) above what is removed in crops). We used modified Hedley fractionation to quantify soil P pools and found increases in less-plant-available inorganic pools and decreases in organic pools in agricultural soils compared with forest. Fertilizer P did not move below 20 cm. Measurements of P sorption capacity suggest that while fertilizer inputs quench close to half of the sorption capacity of fast-reacting pools, most added P is bound in more slowly reacting pools. Our data suggest that this agricultural system currently has a low risk of P losses to waterways and that long time-scales are required to reach critical soil thresholds that would allow continued high yields with reduced fertilizer inputs.

  13. Effects of soya oligosaccharides and soya oligopeptides on lipid metabolism in hyperlipidaemic rats.

    Science.gov (United States)

    Xie, Shali; Zhu, Jundong; Zhang, Yanqi; Shi, Kai; Shi, Yuangang; Ma, Xiao

    2012-08-01

    In the present study, we aimed to examine the effects of soya oligosaccharides (SOS) and soya oligopeptides (SOP) on blood lipid levels, release of vasoactive substances, antioxidant activity and faecal bile acid (FBA) excretion in rats fed a high-fat diet (HFD). Male Sprague-Dawley rats were evenly divided into five groups according to diets as follows: regular diet (control), HFD, HFD enriched with 2 % of SOS (SOS), HFD enriched with 3 % of SOP (SOP) and HFD enriched with 2 % SOS and 3 % SOP (SOSP). The results showed that SOS and SOP significantly reduced plasma total cholesterol, LDL-cholesterol and TAG, whereas HDL-cholesterol concentration was significantly increased. Furthermore, SOS and SOP reduced plasma apoB, apoE and the apoB:apoAI ratio, whereas apoAI was significantly increased. Moreover, SOS and SOP also reduced plasma thromboxane A₂ (TXA₂) and the TXA₂:prostacyclin (PGI₂) ratio, whereas plasma PGI₂ and nitric oxide were significantly increased. In addition, SOS and SOP significantly reduced serum and liver malondialdehyde concentrations and increased FBA excretion. However, we did not observe obvious influences of SOS and SOP on superoxide dismutase activities in the liver of HFD-fed rats. The combination of 2 % SOS and 3 % SOP showed a more marked effect than SOS or SOP alone in improving the lipid profile, release of vasoactive substances and increasing FBA excretion (P blood lipid levels, regulating vasoactive substances and protecting against oxidative stress.

  14. A proteomic study to identify soya allergens--the human response to transgenic versus non-transgenic soya samples.

    Science.gov (United States)

    Batista, Rita; Martins, Isabel; Jeno, Paul; Ricardo, Cândido Pinto; Oliveira, Maria Margarida

    2007-01-01

    In spite of being among the main foods responsible for allergic reactions worldwide, soybean (Glycine max)-derived products continue to be increasingly widespread in a variety of food products due to their well-documented health benefits. Soybean also continues to be one of the elected target crops for genetic modification. The aim of this study was to characterize the soya proteome and, specifically, IgE-reactive proteins as well as to compare the IgE response in soya-allergic individuals to genetically modified Roundup Ready soya versus its non-transgenic control. We performed two-dimensional gel electrophoresis of protein extracts from a 5% genetically modified Roundup Ready flour sample and its non-transgenic control followed by Western blotting with plasma from 5 soya-sensitive individuals. We used peptide tandem mass spectrometry to identify soya proteins (55 protein matches), specifically IgE-binding ones, and to evaluate differences between transgenic and non-transgenic samples. We identified 2 new potential soybean allergens--one is maturation associated and seems to be part of the late embryogenesis abundant proteins group and the other is a cysteine proteinase inhibitor. None of the individuals tested reacted differentially to the transgenic versus non-transgenic samples under study. Soybean endogenous allergen expression does not seem to be altered after genetic modification. Proteomics should be considered a powerful tool for functional characterization of plants and for food safety assessment. Copyright (c) 2007 S. Karger AG, Basel.

  15. Quorum Quenching Bacillus sonorensis Isolated from Soya Sauce Fermentation Brine

    Directory of Open Access Journals (Sweden)

    Kok-Gan Chan

    2012-03-01

    Full Text Available An N-acylhomoserine lactone (AHL-degrading bacterial strain, L62, was isolated from a sample of fermentation brine of Chinese soya sauce by using rich medium agar supplemented with soya sauce (10% v/v. L62, a rod-shaped Gram positive bacterium with amylolytic activity, was phylogentically related to Bacillus sonorensis by 16S ribosomal DNA and rpoB sequence analyses. B. sonorensis L62 efficiently degraded N-3-oxohexanoyl homoserine lactone and N-octanoylhomoserine lactone. However, the aiiA homologue, encoding an autoinducer inactivation enzyme catalyzing the degradation of AHLs, was not detected in L62, suggesting the presence of a different AHL-degrading gene in L62. To the best of our knowledge, this is the first report of AHL-degrading B. sonorensis from soya sauce liquid state fermentation.

  16. Türkiye’de Yetiştirilen bazı Soya Varyetelerinden Elde Edilen Soya Sütlerinin Amino Asit Profilinin Belirlenmesi

    OpenAIRE

    Artık, Nevzat

    1989-01-01

    Bu araştırmada Türkiye’de yetiştirilen 5 farklı soya varyetesinden üretilen soya sütlerinin amino asit profilleri incelenmiştir. Ayrıca Japon soya varyetesi amino asit bileşimi ile karşılaştırma yapılmıştır. Soya sütlerinde esansiyel amino asitler yüksek düzeyde bulunmuştur. Esansiyel amino asit miktarı tüm soya varyetelerinde 4.125, 4.922 (mg/g) sınırları içinde değişmektedir. Bu özelliği ile soya sütü insan beslenmesinde önemli bir gıda maddesidir.  

  17. Türkiye’de Yetiştirilen bazı Soya Varyetelerinden Elde Edilen Soya Sütlerinin Amino Asit Profilinin Belirlenmesi

    Directory of Open Access Journals (Sweden)

    Nevzat Artık

    2015-02-01

    Full Text Available Bu araştırmada Türkiye’de yetiştirilen 5 farklı soya varyetesinden üretilen soya sütlerinin amino asit profilleri incelenmiştir. Ayrıca Japon soya varyetesi amino asit bileşimi ile karşılaştırma yapılmıştır. Soya sütlerinde esansiyel amino asitler yüksek düzeyde bulunmuştur. Esansiyel amino asit miktarı tüm soya varyetelerinde 4.125, 4.922 (mg/g sınırları içinde değişmektedir. Bu özelliği ile soya sütü insan beslenmesinde önemli bir gıda maddesidir.

  18. Immune response in mice to ingested soya protein: antibody production, oral tolerance and maternal transfer

    DEFF Research Database (Denmark)

    Christensen, Hanne Risager; Pedersen, Susanne Brix; Frøkiær, Hanne

    2004-01-01

    by ELISA, and to the presence of oral tolerance detected as a suppressed antibody and cell-proliferation response upon immunisation with soya protein. F0 mice generated soya-specific antibodies, while oral tolerance to the same soya proteins was also clearly induced. When F0 dams were transferred to soya...... antibody response in the offspring, bat in this case in the absence of oral tolerance. This indicates that, under certain conditions, factors involved in spontaneous antibody production can be transmitted from mother to offspring. Understanding the immune response to soya protein ingested under healthy...

  19. Liofilização de fatias de abacaxi: avaliação da cinética de secagem e da qualidade do produto Freeze drying of pineapple slices: evaluation of drying kinetics and product quality

    Directory of Open Access Journals (Sweden)

    Ana Paula Vieira

    2012-03-01

    Full Text Available O objetivo deste trabalho foi avaliar a cinética de secagem e os parâmetros de qualidade - conteúdo de vitamina C, reidratação e textura - de fatias de abacaxi liofilizadas em função da espessura e da temperatura de congelamento. Abacaxis do tipo Havaí, variedade Smooth Cayenne, foram fatiados transversalmente em espessuras de 0,5, 1,0 e 1,5 cm. As fatias foram congeladas nas temperaturas de -14, -24 e -34 °C, sendo, em seguida, conduzidas ao liofilizador. Uma parcela das amostras era destinada ao estudo da cinética de secagem pela pesagem periódica das mesmas, enquanto outra foi reservada para os testes de qualidade. O teor de vitamina C foi quantificado por adição de ácido oxálico na amostra e titulado com 2,6-diclorofenolindofenol. O parâmetro de textura avaliado foi a dureza, por testes de compressão em texturômetro, enquanto a reidratação foi obtida pela pesagem das amostras antes e após a imersão em água destilada por 5 min. Os resultados do presente trabalho mostraram que existe uma forte dependência da cinética de secagem e dos atributos de qualidade de fatias de abacaxi liofilizadas em função das condições utilizadas durante a etapa de congelamento, mesmo sendo este classificado como congelamento lento. Por outro lado, a taxa de congelamento não é a única variável que tem influência sobre a cinética de secagem e os atributos de qualidade. A combinação de temperatura e umidade, tanto durante a liofilização propriamente dita, quanto durante a etapa de reidratação, tem influência sobre a transição vítrea do material que, por sua vez, afeta a extensão do colapso estrutural sofrido pelo produto.The aim of this study was to evaluate the drying kinetics and quality parameters - vitamin C content, rehydration and texture - of freeze dried pineapple slices, according to the thickness and temperature of freezing. Pineapples of the Hawaii type, Smooth Cayenne variety, were sliced transversely with

  20. Obtaining and a comprehensive study of highly bioavailable functional food additives based on Georgian soya varieties

    Directory of Open Access Journals (Sweden)

    M.A. Silagadze

    2017-09-01

    Full Text Available Overall chemical and micro-nutrient composition of Georgian soya varieties grown in different districts of West Georgia have been studied. It was established that “Gurian” soya from Lanchkhuti district is distinguished by the highest content of proteins, fats and dietary fibers that ensures its high functional properties. 18 Aminoacids, mostly fixed in the fractions of globulin and albumin, were identified in protein fractions of Georgian soya varieties that indicates to their high biological value. Highly-bioavailable foods: soya milk, soya pomace and soya flour were obtained during the soya processing; they were tested as food additives in the production of whole wheat bread. Their impact on the fermentation process of wheat dough was studied and the optimal parameters of this process were developed.

  1. Effects of Fermented Soya Bean Supplements on Serum Insulin and ...

    African Journals Online (AJOL)

    This study aimed to evaluate the effects of fermented soya bean supplements on serum insulin and leptin levels of high fat diet-induced type 2 diabetes mellitus in rabbits. Methods: Twenty rabbits of both sexes weighing, 1–2kg were used. Type 2 diabetes was induced by feeding the animals with a high fat diet for eight ...

  2. Utilization of soya protein as an alternative protein source in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-01-05

    Jan 5, 2009 ... source in Oreochromis niloticus diet: Growth performance ... The effect of replacing fish protein with soya protein in tilapia (Oreochromis niloticus) diets was ..... Thomassen MS, Rosjo C (1989). Different fats in feed for salmon: influence on sensory parameters, growth rate and fatty acids in muscle and heart.

  3. Effects of a Proprietary Freeze-Dried Water Extract of Eurycoma longifolia (Physta) and Polygonum minus on Sexual Performance and Well-Being in Men: A Randomized, Double-Blind, Placebo-Controlled Study.

    Science.gov (United States)

    Udani, Jay K; George, Annie A; Musthapa, Mufiza; Pakdaman, Michael N; Abas, Azreena

    2014-01-01

    Background. Physta is a proprietary product containing a freeze-dried water extract of Eurycoma longifolia (tongkat ali), which is traditionally used as an energy enhancer and aphrodisiac. We aim to evaluate a 300 mg combination of Physta and Polygonum minus, an antioxidant, with regard to sexual performance and well-being in men. Methods. Men that aged 40-65 years were screened for this 12-week randomized, double-blind, placebo-controlled, parallel-group study. Outcome measures included validated questionnaires that aimed to evaluate erectile function, satisfaction with intervention, sexual intercourse performance, erectile hardness, mood, and overall quality of life. Results. 12 subjects in the active group and 14 in the placebo group completed the study. Significant improvements were noted in scores for the Sexual Intercourse Attempt diary, Erection Hardness Scale, Sexual Health Inventory of Men, and Aging Male Symptom scale (P < 0.05 for all). Three adverse events were reported in the active group and four in the placebo group, none of which were attributed to study product. Laboratory evaluations, including liver and kidney function testing, showed no clinically significant abnormality. Conclusion. Supplementation for twelve weeks with Polygonum minus and the proprietary Eurycoma longifolia extract, Physta, was well tolerated and more effective than placebo in enhancing sexual performance in healthy volunteers.

  4. Effects of a Proprietary Freeze-Dried Water Extract of Eurycoma longifolia (Physta and Polygonum minus on Sexual Performance and Well-Being in Men: A Randomized, Double-Blind, Placebo-Controlled Study

    Directory of Open Access Journals (Sweden)

    Jay K. Udani

    2014-01-01

    Full Text Available Background. Physta is a proprietary product containing a freeze-dried water extract of Eurycoma longifolia (tongkat ali, which is traditionally used as an energy enhancer and aphrodisiac. We aim to evaluate a 300 mg combination of Physta and Polygonum minus, an antioxidant, with regard to sexual performance and well-being in men. Methods. Men that aged 40–65 years were screened for this 12-week randomized, double-blind, placebo-controlled, parallel-group study. Outcome measures included validated questionnaires that aimed to evaluate erectile function, satisfaction with intervention, sexual intercourse performance, erectile hardness, mood, and overall quality of life. Results. 12 subjects in the active group and 14 in the placebo group completed the study. Significant improvements were noted in scores for the Sexual Intercourse Attempt diary, Erection Hardness Scale, Sexual Health Inventory of Men, and Aging Male Symptom scale (P<0.05 for all. Three adverse events were reported in the active group and four in the placebo group, none of which were attributed to study product. Laboratory evaluations, including liver and kidney function testing, showed no clinically significant abnormality. Conclusion. Supplementation for twelve weeks with Polygonum minus and the proprietary Eurycoma longifolia extract, Physta, was well tolerated and more effective than placebo in enhancing sexual performance in healthy volunteers.

  5. Application of process analytical technology for monitoring freeze-drying of an amorphous protein formulation: use of complementary tools for real-time product temperature measurements and endpoint detection.

    Science.gov (United States)

    Schneid, Stefan C; Johnson, Robert E; Lewis, Lavinia M; Stärtzel, Peter; Gieseler, Henning

    2015-05-01

    Process analytical technology (PAT) and quality by design have gained importance in all areas of pharmaceutical development and manufacturing. One important method for monitoring of critical product attributes and process optimization in laboratory scale freeze-drying is manometric temperature measurement (MTM). A drawback of this innovative technology is that problems are encountered when processing high-concentrated amorphous materials, particularly protein formulations. In this study, a model solution of bovine serum albumin and sucrose was lyophilized at both conservative and aggressive primary drying conditions. Different temperature sensors were employed to monitor product temperatures. The residual moisture content at primary drying endpoints as indicated by temperature sensors and batch PAT methods was quantified from extracted sample vials. The data from temperature probes were then used to recalculate critical product parameters, and the results were compared with MTM data. The drying endpoints indicated by the temperature sensors were not suitable for endpoint indication, in contrast to the batch methods endpoints. The accuracy of MTM Pice data was found to be influenced by water reabsorption. Recalculation of Rp and Pice values based on data from temperature sensors and weighed vials was possible. Overall, extensive information about critical product parameters could be obtained using data from complementary PAT tools. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  6. Optimization of the Synthesis of Structured Phosphatidylcholine with Medium Chain Fatty Acid.

    Science.gov (United States)

    Ochoa-Flores, Angélica A; Hernández-Becerra, Josafat A; Cavazos-Garduño, Adriana; Vernon-Carter, Eduardo J; García, Hugo S

    2017-11-01

    Structured phosphatidylcholine was successfully produced by acidolysis between phosphatidylcholine and free medium chain fatty acid, using phospholipase A 1 immobilized on Duolite A568. Response surface methodology was applied to optimize the reaction system using three process parameters: molar ratio of substrates (phosphatidylcholine to free medium chain fatty acid), enzyme loading, and reaction temperature. All parameters evaluated showed linear and quadratic significant effects on the production of modified phosphatidylcholine; molar ratio of substrates contributed positively, but temperature influenced negatively. Increased enzyme loading also led to increased production of modified phosphatidylcholine but only during the first 9 hours of the acidolysis reaction. Optimal conditions obtained from the model were a ratio of phosphatidylcholine to free medium chain fatty acid of 1:15, an enzyme loading of 12%, and a temperature of 45°C. Under these conditions a production of modified phosphatidylcholine of 52.98 % were obtained after 24 h of reaction. The prediction was confirmed from the verification experiments; the production of modified phosphatidylcholine was 53.02%, the total yield of phosphatidylcholine 64.28% and the molar incorporation of medium chain fatty acid was 42.31%. The acidolysis reaction was scaled-up in a batch reactor with a similar production of modified phosphatidylcholine, total yield of phosphatidylcholine and molar incorporation of medium chain fatty acid. Purification by column chromatography of the structured phosphatidylcholine yielded 62.53% of phosphatidylcholine enriched with 42.52% of medium chain fatty acid.

  7. Inverse association between soya food consumption and insulin resistance in Japanese adults.

    Science.gov (United States)

    Nakamoto, Mariko; Uemura, Hirokazu; Sakai, Tohru; Katsuura-Kamano, Sakurako; Yamaguchi, Miwa; Hiyoshi, Mineyoshi; Arisawa, Kokichi

    2015-08-01

    The purpose of the present study was to examine the association between soya food consumption and insulin resistance using baseline data of the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study in Tokushima, Japan. This cross-sectional study included 1274 subjects, aged 34-70 years at baseline, living in Tokushima Prefecture between 2008 and 2013. Fasting blood samples were collected and information on lifestyle characteristics including soya food intake and medical history were obtained using a structured self-administered questionnaire. The homeostasis model assessment of insulin resistance (HOMA-IR) was measured and those with HOMA-IR ≥ 2.5 were defined as having insulin resistance. Multiple logistic regression models were used to analyse the association between soya product intake and the prevalence of insulin resistance. Rural communities located in Tokushima Prefecture, Japan, between 2008 and 2013. A total of 1148 adults (565 men and 583 women), aged 34-70 years. The frequency of intake of miso soup, total non-fried soya products and total soya products showed significant inverse dose-response relationships with insulin resistance, after adjustments for potential confounders. When soya product intake was calculated as soya protein and isoflavone, the odds ratios of insulin resistance decreased significantly as the estimated intake of soya protein increased. Furthermore, significant inverse dose-response relationships were observed for total non-fried soya products and total soya products, after adjustment for total vegetable or total fibre consumption. The present results indicate that the intake of soya products and non-fried soya products is associated with reduced insulin resistance in the Japanese population.

  8. Protein-stimulated exchange of phosphatidylcholine between intact erythrocytes and various membrane systems

    NARCIS (Netherlands)

    Meer, G. van; Lange, L.G.; Kamp, J.A.F. op den; Deenen, L.L.M. van

    1980-01-01

    Phosphatidylcholine specific exchange protein from beef liver was found to catalyze the exchange of phosphatidylcholine between intact rat and human erythrocytes and various artificial membranes. Both multilamellar liposomes and single bilayer vesicles prepared from egg lecithin, cholesterol and

  9. Sphingomyelin exhibits greatly enhanced protection compared with egg yolk phosphatidylcholine against detergent bile salts

    NARCIS (Netherlands)

    Moschetta, A.; vanBerge-Henegouwen, G. P.; Portincasa, P.; Palasciano, G.; Groen, A. K.; van Erpecum, K. J.

    2000-01-01

    Inclusion of phosphatidylcholine within bile salt micelles protects against bile salt-induced cytotoxicity. In addition to phosphatidylcholine, bile may contain significant amounts of sphingomyelin, particularly under cholestatic conditions. We compared protective effects of egg yolk

  10. The effect of combined Moringa oleifera and demineralized freeze-dried bovine bone xenograft on the amount of osteoblast and osteoclast in the healing of tooth extraction socket of Cavia cobaya

    Directory of Open Access Journals (Sweden)

    Rostiny Rostiny

    2016-12-01

    Full Text Available Background: Alveolar bone has an important role in providing support to teeth and dentures. Loss of support caused by alveolar resorption will cause functional and aesthetic problems. Preservation socket using bone graft is one way to maintain the dimensions of the alveolar bone. Moringa oleifera leaf can increase the activity of bone graft in the formation of new bone. Purpose: This study was aimed to evaluate the effect of combined Moringa oleivera leaf extract and demineralized freeze-dried bovine bone xenograft (DFDBBX towards the formation of osteoblasts and osteoclasts in the tooth extraction sockets of cavia cobaya. Method: This study used 28 cavia cobayas divided into four groups. The combination of Moringa oleifera leaf extract and DFDBBX was inducted into the sockets of lower incisor tooth with certain dose in each group, ointment 1 containing PEG (a mixture of PEG 400 and PEG 4000 for control group, ointment 2 containing Moringa oleifera leaf extract and DFDBBX and PEG (at active subtance consentration of 0.5% for group 1, ointment 3 containing Moringa oleifera leaf extract and DFDBBX and PEG (at active substance concentration of 1% for group 2, and Ointment 4 containing Moringa oleifera leaf extract and DFDBBX and PEG (at active substance consentration of 2% for group 3. paraffin block preparations were made for histopathology examination using hematoxylin eosin staining. Result: The results showed that there were significant differences of the number of osteoblasts and osteoclasts in each treatment group (p <0.05. Conclusion: It can be concluded that the combination of Moringa oleifera leaf extract and DFDBBX at 2% cocentration can increase the number of osteoblasts and decrease osteoclasts in the healing of tooth extraction sockets of cavia cobaya.

  11. Fast analysis of phthalates in freeze-dried baby foods by ultrasound-vortex-assisted liquid-liquid microextraction coupled with gas chromatography-ion trap/mass spectrometry.

    Science.gov (United States)

    Russo, Mario Vincenzo; Avino, Pasquale; Notardonato, Ivan

    2016-11-25

    This paper is focused on the determination of phthalates (PAEs), compounds "plausibly" endocrine disruptors, in baby food products by means of a method based on ultrasound-vortex-assisted liquid-liquid microextraction coupled with GC-IT/MS (UVALLME-GC-IT/MS). Particularly, the whole procedure allows the determination of six phthalates such as DMP, DEP, DBP, iBcEP, BBP and DEHP. After dissolution of 0.1g product sample and addition of anthracene as Internal Standard, 250μL of n-heptane are used as extraction solvent. The solution, held for 5min on the vortex mixer and for 6min in an ultrasonic bath at 100W for favoring the solvent dispersion and consequently the analyte extraction, is centrifuged at 4000rpm for 30min. About 100μL of heptane are recovered and 1μL is injected into the GC-IT/MS. All the analytical parameters investigated are deeply discussed: under the best conditions, the percentage recoveries range between 96.2 and 109.2% with an RSD ≤10.5% whereas the Limit of Detections (LODs) and the Limit of Quantifications (LOQs) are below 11 and 20ngg -1 , respectively, for all the PAEs except for iBcEP (23 and 43ngg -1 , respectively). The linear dynamic range of this procedure is between 10 and 5000ngg -1 with R 2 ≥0.92. The method has been applied to real commercial freeze-dried samples (chicken and turkey meats) available on the Italian pharmaceutical market: three PAEs were preliminary identified, i.e. DEP (14ngg -1 ), DBP (11ngg -1 ) and DEHP (64ngg -1 ). Copyright © 2016. Published by Elsevier B.V.

  12. In vitro comparison of the efficacy of TGF-β1 and PDGF-BB in combination with freeze-dried bone allografts for induction of osteogenic differentiation in MG-63 osteoblast-like cells.

    Science.gov (United States)

    Vahabi, Surena; Torshabi, Maryam; Esmaeil Nejad, Azadeh

    2016-12-01

    Predictable regeneration of alveolar bone defects has always been a challenge in implant dentistry. Bone allografts are widely used bone substitutes with controversial osteoinductive activity. This in vitro study aimed to assess the osteogenic potential of some commercially available freeze-dried bone allografts supplemented with human recombinant platelet-derived growth factor-BB and transforming growth factor beta-1. Cell viability, mineralization, and osteogenic gene expression of MG-63 osteoblast-like cells were compared among the allograft alone, allograft/platelet-derived growth factor-BB, allograft/transforming growth factor beta-1, and allograft/platelet-derived growth factor-BB/transforming growth factor beta-1 groups. The methyl thiazol tetrazolium assay, real-time quantitative reverse transcription polymerase chain reaction and alizarin red staining were performed, respectively, for assessment of cell viability, differentiation, and mineralization at 24-72 h post treatment. The allograft with greater cytotoxic effect on MG-63 cells caused the lowest differentiation among the groups. In comparison with allograft alone, allograft/transforming growth factor beta-1, and allograft/transforming growth factor beta-1/platelet-derived growth factor-BB caused significant upregulation of bone sialoprotein and osteocalcin osteogenic mid-late marker genes, and resulted in significantly higher amounts of calcified nodules especially in mineralized non-cytotoxic allograft group. Supplementation of platelet-derived growth factor-BB alone in 5 ng/mL concentration had no significant effect on differentiation or mineralization markers. According to the results, transforming growth factor beta-1 acts synergistically with bone allografts to enhance the osteogenic differentiation potential. Therefore, this combination may be useful for rapid transformation of undifferentiated cells into bone-forming cells for bone regeneration. However, platelet-derived growth factor

  13. A comparative evaluation of freeze-dried bone allograft with and without bioabsorbable guided tissue regeneration membrane Healiguide® in the treatment of Grade II furcation defects: A clinical study

    Directory of Open Access Journals (Sweden)

    Deept Jain

    2015-01-01

    Full Text Available Background: Furcation defects represent one of the most demanding therapeutic challenges for periodontal therapy. Various treatment modalities have been tried with different success rates. The present study was undertaken to evaluate the efficacy of freeze-dried bone allograft (FDBA with and without bioabsorbable guided tissue regeneration (GTR membrane Healiguide® in the treatment of Grade II furcation defects. Materials and Methods: Ten patients with bilateral Grade II furcation defects were selected for the study. After phase I therapy, subjects were divided into two arms and treated in a split-mouth design. Ten defects were treated with FDBA alone in the control arm. Ten defects were treated with FDBA in conjunction with bioabsorbable GTR membrane Healiguide® in test arm. Clinical parameters lik