The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Fernanda Fonseca - One of the best experts on this subject based on the ideXlab platform.
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Freeze-Drying of bacteria : state of the art and new perspectives
2015Co-Authors: Stéphanie Passot, Stéphanie Cenard, Ioan-cristian Trelea, Fernanda FonsecaAbstract:Freeze-Drying of bacteria : state of the art and new perspectives. 7. International Conference of Lyophilization and Freeze-Drying
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Freeze-Drying of Lactic Acid Bacteria
Methods of Molecular Biology, 2014Co-Authors: Fernanda Fonseca, Stéphanie Cenard, Stéphanie PassotAbstract: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.
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Developing smart control strategies of Freeze-Drying of lactic acid bacteria
2012Co-Authors: Stéphanie Passot, Fernanda Fonseca, Stéphanie Cenard, Ioan-cristian TreleaAbstract:Developing smart control strategies of Freeze-Drying of lactic acid bacteria. 5. International Conference on Lyophilization and Freeze Drying
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Model for Heat and Mass Transfer in Freeze-Drying of Pellets
Journal of Biomechanical Engineering, 2009Co-Authors: Ioan-cristian Trelea, Michèle Marin, Stéphanie Passot, Fernanda FonsecaAbstract:Lyophilizing frozen pellets, and especially spray Freeze-Drying, have been receiving growing interest. To design efficient and safe Freeze-Drying cycles, local temperature and moisture content in the product bed have to be known, but both are difficult to measure in the industry. Mathematical modeling of heat and mass transfer helps to determine local Freeze-Drying conditions and predict effects of operation policy, and equipment and recipe changes on Drying time and product quality. Representative pellets situated at different positions in the product slab were considered. One-dimensional transfer in the slab and radial transfer in the pellets were assumed. Coupled heat and vapor transfer equations between the temperature-controlled shelf, the product bulk, the sub-limationfront inside the pellets, and the chamber were established and solved numerically. The model was validated based on bulk temperature measurement performed at two different locations in the product slab and on partial vapor pressure measurement in the Freeze-Drying chamber. Fair agreement between measured and calculated values was found. In contrast, a previously developed model for compact product layer was found inadequate in describing Freeze-Drying of pellets. The developed model represents a good starting basis for studying Freeze-Drying of pellets. It has to be further improved and validated for a variety ofproduct types and Freeze-Drying conditions (shelf temperature, total chamber pressure, pellet size, slab thickness, etc.). It could be used to develop Freeze-Drying cycles based on product quality criteria such as local moisture content and glass transition temperature.
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Impact of thermal properties on formulation and on Freeze-Drying development
2007Co-Authors: Stéphanie Passot, Fernanda Fonseca, Michèle MarinAbstract:Freeze-Drying continues to increase in importance due to the widespread development of protein therapeutic agents. This results in a great interest in analytical approaches to formulation and process development based on a better understanding of the physical chemistry of freezing and Freeze-Drying. This article describes how two analytical methods, differential scanning calorimetry and Freeze-Drying microscopy can help the formulation scientist to develop the optimum Freeze-dried protein formulation allowing the most efficient Freeze-Drying process.
Takehito Kaneko - One of the best experts on this subject based on the ideXlab platform.
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322 sperm preservation by Freeze Drying in endangered animals
Reproduction Fertility and Development, 2015Co-Authors: Takehito KanekoAbstract:Sperm preservation is a useful tool for conservation of endangered animals. Freeze-Drying sperm have been studied as new preservation method in various mammals as samples can be preserved in a refrigerator at 4°C or ambient temperature. Sperm preservation by Freeze-Drying is the ultimate method by which sperm can be stored that neither required specialised cryoprotectants nor constant supply of liquid nitrogen. We established the Freeze-Drying method that mouse and rat sperm could be preserved long-term at 4°C after Freeze-Drying using a simple solution containing 10 mM Tris and 1 mM EDTA (TE buffer; 2012 PLoS ONE 7, e35043; 2012 Cryobiology 64, 211–214). Using this method, the fertility of the chimpanzee, giraffe, and jaguar sperm after Freeze-Drying were estimated. Ejaculated chimpanzee and giraffe and cauda epididymal jaguar sperm were Freeze-dried using TE buffer. Sperm were rehydrated with sterile distilled water after storage at 4°C for 1 month. Sperm with normal shape were injected into mouse oocytes in CZB medium with HEPES, and oocytes were then cultured in vitro for 6 to 8 h in the same media. In all animals, pronuclei and sperm tail were observed into oocytes without artificial activation after injection of Freeze-dried sperm. When chimpanzee, giraffe, and jaguar sperm were injected into oocytes, 86% (12/14), 100% (12/12), and 96% (22/23) of oocytes formed 2 distinct pronuclei. This study demonstrated that the sperm of various animals could be decondensed into the mouse oocytes after Freeze-Drying using the same protocol. A further advantage is that Freeze-dried sperm can be transported oversea at ambient temperature. Freeze-Drying preservation without using liquid nitrogen can be protected strongly valuable gametes of endangered animals even in the event of unexpected accidents and disaster such as earthquakes and typhoons. Freeze-Drying of sperm has been applied as a “Freeze-Drying zoo” for conservation of endangered animals (http://www.anim.med.kyoto-u.ac.jp/reproduction/home.aspx).
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simple sperm preservation by Freeze Drying for conserving animal strains
Methods of Molecular Biology, 2015Co-Authors: Takehito KanekoAbstract:: Freeze-Drying spermatozoa is the ultimate method for the maintenance of animal strains, in that the gametes can be preserved for a long time in a refrigerator at 4 °C. Furthermore, it is possible to realize easy and safe transportation of spermatozoa at an ambient temperature that requires neither liquid nitrogen nor dry ice. Freeze-Drying spermatozoa has been established as a new method for storing genetic resources instead of cryopreservation using liquid nitrogen. This chapter introduces our latest protocols for Freeze-Drying of mouse and rat spermatozoa, and the anticipated results of the fertilizing ability of these gametes following long-term preservation or transportation.
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c 35 preservation of mammalian sperm by Freeze Drying
Cryobiology, 2014Co-Authors: Takehito KanekoAbstract:Stable conservation of genetic resources is important in various research fields. Sperm preservation is a valuable method for bio-banking of mammalian genetic resources. Freeze-Drying is a useful technique for storing biological materials as samples can be preserved for a long-term in a refrigerator (4 °C). Freeze-Drying sperm has been studied as a new, simple preservation method in various mammals. It is an effective method preservation as it has been reported that offspring could be obtained from mouse and rat sperm preserved long term at 4 °C after Freeze-Drying using a simple solution containing 10 mM Tris and 1 mM EDTA adjusted pH to 8.0 (TE buffer) (Kaneko T., Cryobiology 64, 211–214, 2012; Kaneko T., PLoS One 7, e35043, 2012). Freeze-Drying sperm results in lower costs and increased safety, as specialized cryoprotectants and a constant supply of liquid nitrogen is not required. A further advantage is that Freeze-dried sperm can be temporarily stored at room temperature. Freeze-Drying is possible to transport sperm oversea at ambient temperature that requires neither liquid nitrogen nor dry ice. Furthermore, Freeze-dried valuable samples can be also protected safety even at ambient temperature in the event of unexpected power failure and disaster such as earthquakes and typhoons. At the present, Freeze-Drying sperm has been applied to a “Freeze-Drying Zoo” for conservation of wild endangered animals ( http://www.anim.med.kyoto-u.ac.jp/reproduction/home.aspx ).
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successful long term preservation of rat sperm by Freeze Drying
PLOS ONE, 2012Co-Authors: Takehito Kaneko, Tadao SerikawaAbstract: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.
Stéphanie Passot - One of the best experts on this subject based on the ideXlab platform.
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Freeze-Drying of bacteria : state of the art and new perspectives
2015Co-Authors: Stéphanie Passot, Stéphanie Cenard, Ioan-cristian Trelea, Fernanda FonsecaAbstract:Freeze-Drying of bacteria : state of the art and new perspectives. 7. International Conference of Lyophilization and Freeze-Drying
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Freeze-Drying of Lactic Acid Bacteria
Methods of Molecular Biology, 2014Co-Authors: Fernanda Fonseca, Stéphanie Cenard, Stéphanie PassotAbstract: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.
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Developing smart control strategies of Freeze-Drying of lactic acid bacteria
2012Co-Authors: Stéphanie Passot, Fernanda Fonseca, Stéphanie Cenard, Ioan-cristian TreleaAbstract:Developing smart control strategies of Freeze-Drying of lactic acid bacteria. 5. International Conference on Lyophilization and Freeze Drying
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Model for Heat and Mass Transfer in Freeze-Drying of Pellets
Journal of Biomechanical Engineering, 2009Co-Authors: Ioan-cristian Trelea, Michèle Marin, Stéphanie Passot, Fernanda FonsecaAbstract:Lyophilizing frozen pellets, and especially spray Freeze-Drying, have been receiving growing interest. To design efficient and safe Freeze-Drying cycles, local temperature and moisture content in the product bed have to be known, but both are difficult to measure in the industry. Mathematical modeling of heat and mass transfer helps to determine local Freeze-Drying conditions and predict effects of operation policy, and equipment and recipe changes on Drying time and product quality. Representative pellets situated at different positions in the product slab were considered. One-dimensional transfer in the slab and radial transfer in the pellets were assumed. Coupled heat and vapor transfer equations between the temperature-controlled shelf, the product bulk, the sub-limationfront inside the pellets, and the chamber were established and solved numerically. The model was validated based on bulk temperature measurement performed at two different locations in the product slab and on partial vapor pressure measurement in the Freeze-Drying chamber. Fair agreement between measured and calculated values was found. In contrast, a previously developed model for compact product layer was found inadequate in describing Freeze-Drying of pellets. The developed model represents a good starting basis for studying Freeze-Drying of pellets. It has to be further improved and validated for a variety ofproduct types and Freeze-Drying conditions (shelf temperature, total chamber pressure, pellet size, slab thickness, etc.). It could be used to develop Freeze-Drying cycles based on product quality criteria such as local moisture content and glass transition temperature.
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Impact of thermal properties on formulation and on Freeze-Drying development
2007Co-Authors: Stéphanie Passot, Fernanda Fonseca, Michèle MarinAbstract:Freeze-Drying continues to increase in importance due to the widespread development of protein therapeutic agents. This results in a great interest in analytical approaches to formulation and process development based on a better understanding of the physical chemistry of freezing and Freeze-Drying. This article describes how two analytical methods, differential scanning calorimetry and Freeze-Drying microscopy can help the formulation scientist to develop the optimum Freeze-dried protein formulation allowing the most efficient Freeze-Drying process.
Ioan-cristian Trelea - One of the best experts on this subject based on the ideXlab platform.
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Freeze-Drying of bacteria : state of the art and new perspectives
2015Co-Authors: Stéphanie Passot, Stéphanie Cenard, Ioan-cristian Trelea, Fernanda FonsecaAbstract:Freeze-Drying of bacteria : state of the art and new perspectives. 7. International Conference of Lyophilization and Freeze-Drying
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Developing smart control strategies of Freeze-Drying of lactic acid bacteria
2012Co-Authors: Stéphanie Passot, Fernanda Fonseca, Stéphanie Cenard, Ioan-cristian TreleaAbstract:Developing smart control strategies of Freeze-Drying of lactic acid bacteria. 5. International Conference on Lyophilization and Freeze Drying
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Model for Heat and Mass Transfer in Freeze-Drying of Pellets
Journal of Biomechanical Engineering, 2009Co-Authors: Ioan-cristian Trelea, Michèle Marin, Stéphanie Passot, Fernanda FonsecaAbstract:Lyophilizing frozen pellets, and especially spray Freeze-Drying, have been receiving growing interest. To design efficient and safe Freeze-Drying cycles, local temperature and moisture content in the product bed have to be known, but both are difficult to measure in the industry. Mathematical modeling of heat and mass transfer helps to determine local Freeze-Drying conditions and predict effects of operation policy, and equipment and recipe changes on Drying time and product quality. Representative pellets situated at different positions in the product slab were considered. One-dimensional transfer in the slab and radial transfer in the pellets were assumed. Coupled heat and vapor transfer equations between the temperature-controlled shelf, the product bulk, the sub-limationfront inside the pellets, and the chamber were established and solved numerically. The model was validated based on bulk temperature measurement performed at two different locations in the product slab and on partial vapor pressure measurement in the Freeze-Drying chamber. Fair agreement between measured and calculated values was found. In contrast, a previously developed model for compact product layer was found inadequate in describing Freeze-Drying of pellets. The developed model represents a good starting basis for studying Freeze-Drying of pellets. It has to be further improved and validated for a variety ofproduct types and Freeze-Drying conditions (shelf temperature, total chamber pressure, pellet size, slab thickness, etc.). It could be used to develop Freeze-Drying cycles based on product quality criteria such as local moisture content and glass transition temperature.
Anerl V King - One of the best experts on this subject based on the ideXlab platform.
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effects of far infrared radiation on the Freeze Drying of sweet potato
Journal of Food Engineering, 2005Co-Authors: Jenhorng Tsen, Anerl V KingAbstract:Abstract An experimental dryer was developed to determine the Drying characteristics of sweet potato during Freeze-Drying with far-infrared radiation. The experimental Drying time of sweet potato cubes dehydrated by three Drying methods, i.e., air-Drying, Freeze-Drying, and Freeze-Drying with far-infrared radiation, were compared, and Freeze-Drying with far-infrared radiation was found to be able to reduce the Drying time of sweet potato. Both constant and falling rate Drying periods were observed, and empirical equations were developed to study the behavior of Drying rate in falling rate period. On the other hand, four mathematical models were used to describe the Drying characteristics of sweet potato during Freeze-Drying with far-infrared radiation. The coefficients of determination (R2) in the exponential, Page, and approximate diffusion model were found to be above 0.98, and that of diffusion model was above 0.92. The rank of fitness of those models was Page, approximate diffusion, exponential and diffusion model. The choice of Page model was evident because of the lowest residual as well as RMSE. The Page model described the far-infrared Freeze-Drying characteristics of sweet potato properly.
