bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bioprinting
Authors: Phamduy Theresa B. , Corr David T. , Chrisey Douglas B. 
Published: April 2010

AbstractBioprinting refers to the spatially‐controlled deposition of disparate biomaterials that is carried out by various printing techniques for the bottom‐up transfer of cells, biomolecules, and scaffold. The applications and techniques for bioprinting discussed in this chapter address the emergent demands of sub‐micrometer patterns for fundamental study, device construction, and bottom‐up tissue engineering. The advantages of bioprinting stem from its unique attributes of controllability, automated deposition, CAD/CAM construction, bottom‐up writing, and rapid prototyping. As advancements in biotechnology gravitate towards the micro‐scale and nano‐scale, precise deposition of biomaterial patterns becomes critical for many applications, including biomedical devices. In addition, the drive for the rapid prototyping of tissue constructs requires the combination of computer aided design and high‐resolution repeatability that bioprinting is able to achieve. Examples of bioprinting methods include patterning, ink‐jet based bioprinting, laser deposition, and nanobioprinting. Bioprinting is poised to be a significant tool for metric transfers of fragile biomaterials in both biomedical engineering research and industrial biotechnology applications.
High‐Throughput Technologies in Bioprocess Development
Authors: Carrier Trent , Heldin Eva , Ahnfelt Mattias , Brekkan Eggert , Hassett Richard , Peppers Steve , Rodrigo Gustav , Van Slyke Greg , Zhao David (Xiaojian) 
Published: April 2010

Abstract
Bioprocess development is a relatively new field for the application of high‐throughput technologies (HTT). Similar to historical applications in drug discovery, these new tools are generally being applied to increase throughput and efficiency to either enable improved performance by testing a larger experimental design space or improve speed for development for biological pipelines. In surveying the general application of these technologies in the biotechnology industry, it becomes clear that HTT have targeted a few key steps within upstream and downstream process development workflows (also called HTPD i.e. high‐throughput process development). The primary focus for upstream HTT has been cell line selection and cell culture development, whereas downstream HTT has centered on the chromatography unit operation. The successful implementation of these technologies has come with many lessons learned on technology selection, workflow validation, and study execution. Furthermore towards improving the application of HTT, analytical techniques in combination with experimental design strategies have been developed that enable larger and more complete scientific investigation of experimental conditions. The complete set of tools, techniques, and design strategies have yielded tangible benefits for early adopters, particularly where capacity and timeline restrictions create workflow bottlenecks. Applied properly, high‐throughput technologies can be an important tool in meeting the bioprocess challenges of today and tomorrow.
Bioreactor Scale‐Down
Authors: Palomares Laura A. , Lara Alvaro R. , RamÍRez Octavio T. 
Published: April 2010

Abstract
In this chapter, scale‐down methodology is described as a useful tool to study the effects of fluctuating conditions on large‐scale bioreactors. The scale‐down approach focuses on simulating, on the laboratory scale, the environmental conditions prevalent on the large scale and analyzing the effects of these fluctuations on cell physiology. The scale‐down approach consists of the following steps: regime analysis of the large‐scale conditions, their simulation on laboratory systems, optimization and modeling of the cultures, and the application of the results on the large scale. These steps are presented and discussed. A review of the published scale‐down studies in cell culture and microbial fermentation is also included. Finally, an overview of the most commonly used scale‐down systems for simulating environmental fluctuations is presented, emphasizing their advantages and limitations for their use on microbial or animal cells models.
Bioreactors, Fluidized‐Bed
Authors: Storhas Winfried 
Published: April 2010

AbstractThe traditional 50‐year old fluidized‐bed technology has become an important tool in new patterns for modern biotechnological processes. All biotechnological processes use biocatalysts as cells or isolated enzymes. To handle these biocatalysts in an economical way, they have to be kept in the bioreactor. Therefore carrier systems are used.A suitable concept to handle economically carrier systems for retention enzymes and cells in a system is the fluidized‐bed reactor (FBR). FBRs can be run between two velocities. Starting with a very low superficial velocity, the packing of carriers keeps in the fixed‐bed manner till the incipient fluidization point. Then, the system changes into an FBR and remains there till the entrainment velocity (wash‐out point).To design FBR one uses fluidized bed state diagram (Reh). With the dimensionless numbers Archimedes and Omega in the fluidized bed state diagram all the necessary conditions can be found for the process, especially the suitable velocity. This can occur between the incipient fluidization and the entrainment velocity. The key for the final design is the power input into the bioreactor.
Bioreactors, Stirred Tank for Culture of Plant Cells
Authors: Doran Pauline M. 
Published: April 2010

AbstractBioreactors with mechanical stirring offer important advantages for large‐scale culture of suspended plant cells. Greater power can be input to the culture compared with air‐driven reactors; for viscous broths containing high cell densities, this translates into better mixing and oxygen transfer. The availability of two independent means of manipulating the hydrodynamic environment, adjusting the stirring speed and gas flow rate, also allows greater flexibility of reactor operation than in air‐driven systems. Yet, these potential advantages may never be realized in full in any particular plant cell application because the mechanical forces generated by conventional impellers and the shear sensitivity of the cells limit the operating conditions that can be employed. Reactor engineering and innovation in this area are aimed at finding an appropriate balance between the beneficial and destructive effects of energy dissipation and hydrodynamic shear in plant cell suspensions. To this end, a wide range of vessel, impeller, and sparger configurations has been applied in experimental studies. This article outlines the function of stirring equipment with reference to plant cell systems and the effect of reactor operating conditions on culture performance.
Bioreduction
Authors: Skorupa Parachin Nádia , Carlquist Magnus , Gorwa‐Grauslund Marie‐F 
Published: April 2010

AbstractBioreduction has emerged over the years as an alternative method to organic synthesis for the generation of chiral precursors of commercial interest. Bioreductions operate under mild conditions of pH and temperature with the help of highly regio‐ and enantio‐selective oxidoreductase enzymes.In this contribution, the different oxidoreductase families involved in bioreductions are exemplified and their main characteristics are presented. The wide spectrum of oxidoreductase substrates (including ketones, diketones, ketoesters, aldehydes, alkenes, and keto acids) is discussed and both preparative and industrial scale examples are reported. The advantages and disadvantages of using isolated enzymatic systems versus whole‐cell systems for bioreduction are discussed in terms of cost, specificity, stereoselectivity, and cofactor regeneration. The contribution is also reviewing strategies for improving the biocatalyst at the cell or enzyme level, which include process engineering, metabolic engineering as well as structure‐based and nonstructure‐based enzyme engineering. Finally, the potential role of metagenomics for isolating novel biocatalysts from different environments is discussed.
Bioremediation
Authors: Ward Owen P. 
Published: April 2010

AbstractBioremediation, which exploits biological processes to remove contaminants from the biosphere, is generally a low‐cost option among remediation alternatives. The organisms involved are predominantly microbes which have the capacity to survive contaminant toxicity and access and transform the contaminants. Many contaminants are organic solvents which disrupt membranes, and cells may develop defence mechanisms including formation of outer cell‐membrane‐protective material, often hydrophobic or solvent efflux pumps. Many of the contaminants are hydrophobic and microbial species appear to take up these substances by a combination of biosurfactant secretion and direct cell‐contaminant association. Bioremediation may involve aerobic or anaerobic microbial activities. Aerobic degradation often involves introduction of oxygen atoms in reactions mediated by monooxygenases, dioxygenases, hydroxylases, oxidative dehalogenases, or chemically reactive oxygen atoms generated by enzymes such as ligninases or peroxidases. Anaerobic degradations of predominant contaminants such as petroleum hydrocarbons, typically involve initial activation reactions followed by oxidative catabolism mediated by anoxic electron acceptors. Many microbes participate in bioremediation processes by mineralizing the organic contaminants to end‐products such as carbon dioxide and water, or to metabolic intermediates which are used as primary substrates for cell growth. Cells may be able to biotransform the contaminant without being able to utilize the contaminant for growth in a process known as cometabolism. Microbes have also evolved biocatalytic systems which indirectly mediate the transformation of some recalcitrant molecular species, mediated by enzymes which generate chemically reactive species which in turn, attack the recalcitrant molecules.Major strategies for implementing bioremediation processes include biostimulation and bioaugmentation approaches. Biostimulation involves adding supplements to a contaminated site with the objective of stimulating growth of the microbial population already present there, which may be capable of degrading the contaminants. Where the contaminated environment does not contain microbes capable of degrading the contaminants, there may be a case for addition of a selected and acclimated microbial inoculum. This is termed bioaugmentation. Widely used process configurations include slurry bioreactors, landfarming, soil‐pile composting systems, engineered soil piles,in situsubsurface bioremediation and phytoremediation. Bioremediation accounts only for a small fraction of the remediation market because arguably, some of the processes implemented failed to meet the required contaminant reduction criteria. For bioremediation processes to gain access to a more substantial proportion of the remediation market, processes must be judiciously selected to be technically dependable and cost‐effective.
Biosensors, Environmental
Authors: Bassi Amarjeet S. 
Published: April 2010

AbstractIn this article, the principles and applications of biosensors for environmental monitoring are presented. Biosensors represent an interesting and relevant approach to overcome the shortcomings in the diverse areas of environmental monitoring. Biosensors can complement laboratory‐based analytical techniques and can also be applied for real‐time field applications. The current approaches using nano and micro sensors, multiple arrays, and interfacing with remote monitoring systems are making biosensor technology the technology of choice for environmental mapping, robots, security, and other areas of relevance. In this article, the principles of biosensors for environmental applications are reviewed. Some new approaches available for biosensor design are also presented.
Biosensors, Foodborne Pathogen Detection
Authors: Bhunia Arun K. , Nanduri Viswaprakash , Bae Euiwon , Hirleman E. Dan 
Published: April 2010

Abstract

In recent years, foodborne pathogens have become a significant concern due to increasing numbers of outbreaks and the resulting fatalities and economic losses. In addition to improving hygienic practices in food production and preparation, improvement in pathogen testing is urgently needed. Conventional culture‐based methods are lengthy, involve multiple steps, and lack sensitivity. Even the so‐called antibody‐ or nucleic acid‐based “rapid methods” require a minimum of 24–48 h to complete. Faster and more sensitive detection methods are needed, and biosensor‐based methods have the capacity to meet that need. In this review, we describe developments in the area of select sensors that show promise for foodborne pathogen detection, including
Fourier Transform InfraRed spectroscopy
(FTIR), light scattering,
surface plasmon resonance
(SPR), fiber optic, microfluidic protein biochip, and mammalian cell‐based sensors. FTIR and light‐scattering sensors are considered label‐free methods since they do not require any probes or labeling reagents. SPR is a semi‐label‐free method since it requires recognition molecules such as antibodies, nucleic acids, aptamers, or bacteriophages for detection. The remaining methods require labeling reagents and probes. Application and utilization of these biosensors in pathogen detection are also highlighted.
Biotransformation, Process Optimization, Kinetics and Engineering Aspects
Authors: Hilterhaus Lutz , Liese Andreas , Kragl Udo 
Published: April 2010

AbstractThe use of biotransformations in the food, pharmaceutical, and chemical industries has increased steadily since the early 1970s. Applications range from synthesis in the milligram scale for precious oligosaccharides up to multiton scale for bulk chemicals either using whole cells or isolated enzymes. When new processes are being developed, the special properties of the biocatalyst must be considered, as well as the basic elements of chemical engineering. There is a strong interaction among the individual aspects, which may be considered for process optimization.The intention of this article is to outline the basic strategy for the development of a biocatalytic step. For some selected examples the beneficial role of biochemical engineering is demonstrated.
Large‐Scale Chromatography Columns, Modeling Flow Distribution
Authors: Fang Zhiwu 
Published: April 2010

AbstractLiquid chromatography has become an indispensable tool in the pharmaceutical and biotechnology industries for preparative and large‐scale purifications to obtain high purity biopharmaceutical products. However, imperfect packing of the column bed and complex rheological behaviors of resin particles pose a great challenge for any modeling effort.A systematic study, based on rigorous physics, which attempts to understand the intrinsic complicated interrelationships between column packing, hardware design, flow distribution, and separation efficiency would be of great help to chromatography practitioners. Seeing this need, this article makes an effort to perform a systematic study of the chromatography processes from start to finish and to provide mathematical models and case studies for each stage. First, the author discusses the challenges in scaling up chromatography column packing and examines the wall effect through a dimensional analysis, then follows it by introducing a one‐dimensional model, describing column packing and scale‐up. Next, the author presents a case study on a commercial scale column with a special headplate design and investigates the impact of hardware design on flow distribution, using the technique of computational fluid dynamics (CFD). Finally, this article presents simulations on the transport of elute and computation on the height equivalent to a theoretic plate (HETP) in a modeled, large column set for no retention, ion exchange, and affinity systems. The author discovers that the hardware design exerts a great impact on the flow distribution in the columns and thus affects the column separation efficiency to a large extent.
Spectral Data Comparability–Acceptance Criteria Definition by Statistical Analysis
Authors: Bierau Horst , Tranter George E. , Le Pevelen Delphine D. , Giartosio Carlo E. , Jone Carl S. 
Published: April 2010

Abstract
An approach is proposed to define unequivocal acceptance criteria for circular dichroism (CD) spectra, which eliminates operator bias associated with visual assessment of sample versus reference spectra. It is based on a statistical analysis of reference data obtained and allows distinguishing the variation inherent in a given set of reference spectra from genuine structural differences that may be present in a sample. This approach was successfully applied for comparing CD spectra in the framework of a comparability study of a marketed biopharmaceutical. Moreover, the proposed approach is generic and may readily be adapted to analyze spectral data obtained from techniques other than CD.
Clostridium
Authors: Schiel Bettina , Dürre Peter 
Published: April 2010

AbstractSpecies of the genusClostridiumare Gram‐positive, strictly anaerobic or moderately aerotolerant bacteria, producers of endospores, and unable of dissimilatory sulfate reduction. Clostridia are able to metabolize a variety of substances, and the respective fermentation pathways are diverse. Meanwhile, all techniques (culturing techniques and techniques for genetic manipulation) necessary to effectively work with clostridia in the laboratory are established. Clostridia are often considered as dangerous to humankind. This is due to the well‐known speciesC. botulinumandC. tetaniproducing the most dangerous natural toxins (botulinum toxin and tetanus toxin, respectively). Albeit very famous, these and some other dangerous species represent a minority within the genusClostridium. The majority of the approximately 150 validly describedClostridiumspecies are absolutely safe to mankind, and moreover, they are of utmost importance for biotechnological processes (e.g. production of biofuels, bulk chemicals) and medical treatments (e.g. cancer treatment). Even the above mentioned botulinum toxin is nowadays used to treat diseases, and it is even more popular as a tool in cosmetics. The versatile use of differentClostridiumspecies turns the genus to the avant‐garde of industrially useful microorganisms. The biotechnological and medical potentials of this genus are underlined by a number of books devoted to this specific group of bacteria that have been published in the last 19 years.
Protein Crystallization, Kinetics
Authors: Profio Gianluca Di , Curcio Efrem , Drioli Enrico 
Published: April 2010

AbstractProtein crystallization has become today a fundamental operation in scientific, technological, and industrial sectors. The principal aim of crystal growers is to obtain protein crystals with specific characteristics. Large, well‐diffracting crystals are necessary for tridimensional structure resolution at atomic level by X‐ray diffraction analysis, while smaller, monodispersed in size and uniformly shaped crystals are required in some industrial sectors as, for example, environmental protection, chemical synthesis, and heterogeneous catalysis. However, the production of crystals with opportune properties can only be realized by a fine control of the crystallization kinetics throughout its several steps. The main difficulty in achieving this goal is the poor understanding of the crystallization mechanism in its various aspects, especially for proteins, due to their structural complexity. Generally, theories developed for small molecules crystallization have been extended to proteins. However, although in certain circumstances proteins crystallize by the same mechanisms, they have some of their own peculiarities. These differences can be ascribed to the asymmetric and weak bonding configuration at the protein surface, the tendency to aggregate inn‐mers, the sensitivity to contaminants and impurities, the formation of precipitates, oils or gels and the low diffusivities in solution. As a result, protein crystallization is a complicated physical–chemical process not fully described by simple theory.In this contribution, the different steps involved during protein crystallization are discussed. These include the initial interaction of protein in solution, their aggregation to form stable nuclei—even when it is promoted by heterogeneous substrates, the growth to macroscopic crystals, and the case of growth in forced solution convection regime.
Dehydrogenases, Electrochemical Cofactor Regeneration
Authors: Kornberger Petra , Giffhorn Friedrich , Kohring Gert‐Wieland 
Published: April 2010

AbstractDehydrogenases represent a valuable tool in biotechnology for the production of fine chemicals and reactive compounds and as the building blocks of pharmaceutical and agrochemical active substances. Their activity in regiospecific and enantioselective hydroxyl group oxidation and ketone reduction has attracted increasing interest with respect to production processes, design of biosensors, and construction of biofuel cells. However, the electron transfer cofactors necessary for their enzymatic activity are usually high priced and, therefore, have to be regenerated in the corresponding processes. In the last few decades, multiple regeneration procedures have been developed for different groups of dehydrogenases with application potential; for example, whole cell systems, cofactor regeneration with a second substrate and/or a second enzyme, and photochemical or electrochemical methods. Here, we discuss the different systems with focus on electrochemical restoration of redox equivalents.
Cleaning and Sanitization in Downstream Processing
Authors: Sofer Gail , Robinson Craig , Yourkin Jonathan , Pitarresi Tina , Birse Darcy 
Published: April 2010

Abstract

Downstream processing of biopharmaceuticals typically includes chromatography and filtration unit operations. Downstream processing enables the production of highly purified biological therapeutic products for preclinical testing, clinical and commercial use. The design and implementation of suitable cleaning protocols are part of regulatory commitments ensuring the consistent production and control of manufacturing conditions for biotherapeutics. In current modern biomanufacturing, cleaning and validation remain critical concerns for industrial biotechnology products and processes. In this article, the review focuses on cleaning and sanitization of chromatography media, membranes, and equipment for the production of biotherapeutics and
in vivo
diagnostics. The Cleaning and Cleaning Validation principles described in this review apply to the production of a range of biotechnology products including biotherapeutics such as vaccines [nucleic acid (DNA, RNA) viruses, antigens, and polysaccharides], MAbs, recombinant proteins (rProteins), and peptides.
Energy Metabolism of Cells Used for Industrial Production
Authors: Butler Michael , Sparling Richard , Court Deborah 
Published: April 2010

AbstractThe metabolic pathways of bacterial, fungal and animal cells used in industrial bioprocesses are described. Some of the pathways of catabolism utilizing carbohydrates such as glucose for energy and reducing equivalents are common to many of these cells. Cells used in industrial processes are commonly selected or genetically engineered to allow the synthesis of specific products required in large quantities. Some of these products are the end‐points of catabolic pathways and include ethanol, acetate and lactate. Secondary metabolites have been the source of many pharmaceutical products such as antibiotics, which are produced from fungal fermentation. Animal cells in culture have been the basis of bioprocesses used to produce recombinant glycoproteins many of which are developed as novel biopharmaceuticals. These cultures require careful design of culture conditions to maximize cell growth and productivity.