Bioprocess

Abstract: Preface to the Second Edition. Preface to the First Edition. I. INTRODUCTION. 1. What is a Bioprocess Engineer? Introductory Remarks. Biotechnology and Bioprocess Engineering. Biologists and Engineers Differ in Their Approach to Research. The Story of Penicillin: How Biologists and Engineers Work Together. Bioprocesses: Regulatory Constraints. Suggestions for Further Reading. Problems. II. THE BASICS OF BIOLOGY: AN ENGINEER'S PERSPECTIVE. 2. An Overview of Biological Basics. Are All Cells the Same? Cell Construction. Cell Nutrients. Summary. Suggestions for Further Reading. Problems. 3. Enzymes. Introduction. How Enzymes Work. Enzyme Kinetics. Immobilized Enzyme Systems. Large-scale Production of Enzymes. Medical and Industrial Utilization of Enzymes. Summary. Suggestions for Further Reading. Problems. 4. How Cells Work. Introduction. The Central Dogma. DNA Replication: Preserving and Propagating the Cellular Message. Transcription: Sending the Message. Translation: Message to Product. Metabolic Regulation. How the Cell Senses Its Extracellular Environment. Summary. Appendix: Examples of Regulation of Complex Pathways. Suggestions for Further Reading. Problems. 5. Major Metabolic Pathways. Introduction. Bioenergetics. Glucose Metabolism: Glycolysis and the TCA Cycle. Respiration. Control Sites in Aerobic Glucose Metabolism. Metabolism of Nitrogenous Compounds. Nitrogen Fixation. Metabolism of Hydrocarbons. Overview of Biosynthesis. Overview of Anaerobic Metabolism. Overview of Autotrophic Metabolism. Summary. Suggestions for Further Reading. Problems. 6. How Cells Grow. Introduction. Batch Growth. Quantifying Growth Kinetics. How Cells Grow in Continuous Culture. Summary. Suggestions for Further Reading. Problems. 7. Stoichiometry of Microbial Growth and Product Formation. Introduction. Some Other Definitions. Stoichiometric Calculations. Theoretical Predictions of Yield Coefficients. Summary. Suggestions for Further Reading. Problems. 8. How Cellular Information is Altered. Introduction. Evolving Desirable Biochemical Activities through Mutation and Selection. Natural Mechanisms for Gene Transfer and Rearrangement. Genetically Engineering Cells. Genomics. Summary. Suggestions for Further Reading. Problems. III. ENGINEERING PRINCIPLES FOR BIOPROCESSES. 9. Operating Considerations for Bioreactors for Suspension and Immobilized Cultures. Introduction. Choosing the Cultivation Method. Modifying Batch and Continuous Reactors. Immobolized Cell Systems. Solid-state Fermentations. Summary. Suggestions for Further Reading. Problems. 10. Selection, Scale-Up, Operation, and Control of Bioreactors. Introduction. Scale-up and Its Difficulties. Bioreactor Instrumentation and Control. Sterilization of Process Fluids. Summary. Suggestions for Further Reading. Problems. 11. Recovery and Purification of Products. Strategies to Recover and Purify Products. Separation of Insoluble Products. Cell Disruption. Separation of Soluble Products. Finishing Steps for Purification. Integration of Reaction and Separation. Summary. Suggestions for Further Reading. Problems. IV. APPLICATIONS TO NONCONVENTIONAL BIOLOGICAL SYSTEMS. 12. Bioprocess Considerations in Using Animal Cell Cultures. Structure and Biochemistry of Animal Cells. Methods Used for the Cultivation of Animal Cells. Bioreactor Considerations for Animal Cell Culture. Products of Animal Cell Cultures. Summary. Suggestions for Further Reading. Problems. 13. Bioprocess Considerations in Using Plant Cell Cultures. Why Plant Cell Cultures? Plant Cells in Culture Compared to Microbes. Bioreactor Considerations. Economics of Plant Cell Tissue Cultures. Summary. Suggestions for Further Reading. Problems. 14. Utilizing Genetically Engineered Organisms. Introduction. How the Product Influences Process Decisions. Guidelines for Choosing Host-Vector Systems. Process Constraints: Genetic Instability. Considerations in Plasmid Design to Avoid Process Problems. Predicting HostDVector Interactions and Genetic Instability. Regulatory Constraints on Genetic Processes. Metabolic Engineering. Protein Engineering. Summary. Suggestions for Further Reading. Problems. 15. Medical Applications of Bioprocess Engineering. Introduction. Tissue Engineering. Gene Therapy Using Viral Vectors. Bioreactors. Summary. Suggestions for Further Reading. Problems. 16. Mixed Cultures. Introduction. Major Classes of Interactions in Mixed Cultures. Simple Models Describing Mixed-culture Interactions. Mixed Cultures in Nature. Industrial Utilization of Mixed Cultures. Biological Waste Treatment: An Example of the Industrial Utilization of Mixed Cultures. Summary. Suggestions for Further Reading. Problems. 17. Epilogue. Appendix: Traditional Industrial Bioprocesses. Anaerobic Bioprocesses. Aerobic Processes. Suggestions for Further Reading. Index.

Abstract: Biologically mediated processes seem promising for energy conversion, in particular for the conversion of lignocellulosic biomass into fuels. Although processes featuring a step dedicated to the production of cellulase enzymes have been the focus of most research efforts to date, consolidated bioprocessing (CBP)--featuring cellulase production, cellulose hydrolysis and fermentation in one step--is an alternative approach with outstanding potential. Progress in developing CBP-enabling microorganisms is being made through two strategies: engineering naturally occurring cellulolytic microorganisms to improve product-related properties, such as yield and titer, and engineering non-cellulolytic organisms that exhibit high product yields and titers to express a heterologous cellulase system enabling cellulose utilization. Recent studies of the fundamental principles of microbial cellulose utilization support the feasibility of CBP.

Abstract: Recalcitrance to saccharification is a major limitation for conversion of lignocellulosic biomass to ethanol. In stems of transgenic alfalfa lines independently downregulated in each of six lignin biosynthetic enzymes, recalcitrance to both acid pretreatment and enzymatic digestion is directly proportional to lignin content. Some transgenics yield nearly twice as much sugar from cell walls as wild-type plants. Lignin modification could bypass the need for acid pretreatment and thereby facilitate bioprocess consolidation.

Abstract: In aerobic bioprocesses, oxygen is a key substrate; due to its low solubility in broths (aqueous solutions), a continuous supply is needed. The oxygen transfer rate (OTR) must be known, and if possible predicted to achieve an optimum design operation and scale-up of bioreactors. Many studies have been conducted to enhance the efficiency of oxygen transfer. The dissolved oxygen concentration in a suspension of aerobic microorganisms depends on the rate of oxygen transfer from the gas phase to the liquid, on the rate at which oxygen is transported into the cells (where it is consumed), and on the oxygen uptake rate (OUR) by the microorganism for growth, maintenance and production. The gas-liquid mass transfer in a bioprocess is strongly influenced by the hydrodynamic conditions in the bioreactors. These conditions are known to be a function of energy dissipation that depends on the operational conditions, the physicochemical properties of the culture, the geometrical parameters of the bioreactor and also on the presence of oxygen consuming cells. Stirred tank and bubble column (of various types) bioreactors are widely used in a large variety of bioprocesses (such as aerobic fermentation and biological wastewater treatments, among others). Stirred tanks bioreactors provide high values of mass and heat transfer rates and excellent mixing. In these systems, a high number of variables affect the mass transfer and mixing, but the most important among them are stirrer speed, type and number of stirrers and gas flow rate used. In bubble columns and airlifts, the low-shear environment compared to the stirred tanks has enabled successful cultivation of shear sensitive and filamentous cells. Oxygen transfer is often the rate-limiting step in the aerobic bioprocess due to the low solubility of oxygen in the medium. The correct measurement and/or prediction of the volumetric mass transfer coefficient, (k(L)a), is a crucial step in the design, operation and scale-up of bioreactors. The present work is aimed at the reviewing of the oxygen transfer rate (OTR) in bioprocesses to provide a better knowledge about the selection, design, scale-up and development of bioreactors. First, the most used measuring methods are revised; then the main empirical equations, including those using dimensionless numbers, are considered. The possible increasing on OTR due to the oxygen consumption by the cells is taken into account through the use of the biological enhancement factor. Theoretical predictions of both the volumetric mass transfer coefficient and the enhancement factor that have been recently proposed are described; finally, different criteria for bioreactor scale-up are considered in the light of the influence of OTR and OUR affecting the dissolved oxygen concentration in real bioprocess.

Abstract: This welcome new edition discusses bioprocess engineering from the perspective of biology students. It includes a great deal of new material and has been extensively revised and expanded. These updates strengthen the book and maintain its position as the book of choice for senior undergraduates and graduates seeking to move from biochemistry/microbiology/molecular biology to bioprocess engineering. New to this edition: * All chapters thoroughly revised for current developments, with over 200 pgs of new material, including significant new content in: * Metabolic Engineering * Sustainable Bioprocessing * Membrane Filtration * Turbulence and Impeller Design * Downstream Processing * Oxygen Transfer Systems * Over 150 new problems and worked examples * More than 100 new illustrations