Highly Selective Separations In Biotechnology

Success in meeting the challenge to produce the commercial products anticipated by the exploitation of biological processes depends upon provid ing effective separation protocols. Effectiveness can be measured in terms of selectivity, purity, resolution and validatory success. The major processing problems are associated with either the selective recovery of molecules which are present in low concentrations from complex mixtures or the selective removal of contaminants from the desired molecule. Central to the evolution of processes satisfying this demand are the regulatory requirements being imposed by governments on the purity of a product, especially in the health care market. Synthetic organic chemists are increasingly finding it advantageous to conduct one or more steps using either enzymic biotransformations where molecules with a single and consistent stereochemistry or chirality are required. The underlying princi ples behind the methods, techniques and processes currently being used and developed commercially rely upon the biospecific nature and properties of the desired molecule. When these factors are married to the more traditional techniques of precipitation, chromatography, liquid-liquid extraction and membrane processes, powerful tools emerge, allowing highly selective separations to be designed. The logical extension of these combinations is to apply genetic engineering techniques to influence the separations at a more fundamental and structural level by modifying the target protein at source, during its synthesis, to facilitate its separation in a given, selective manner, leading to the distinct possibility of producing 'designer' separation programmes.

The challenge of bioseparations is to isolate and purify identified products from the dilute product broth produced from cell culture. Innovation in bioseparations technology is increasingly driven by the requirements imposed by the growing importance of production on a process scale of injectable-grade products, and economic pressures to improve the efficiency of downstream processing. As in other areas of technical change, science does not necessarily precede new technology: progress results from a complex and messy mixture of advances in understanding, ingenious ideas, novel techniques and chance discoveries. What is certain is that close interaction between academics and practitioners, biological scientists and process engineers is needed to solve the problems of bioseparations. The Second International Conference on Separations for Biotechnology at Reading, UK, in September 1990 set out to provide a critical multidisciplinary forum for the discussion of bioseparations. This volume contains the papers presented at the meeting. The meeting was organised around six themes with oral and poster presentations on the science and practice of bioseparations technology, and the same structure has been kept for this book. We have also included the texts of the keynote review paper by Professor Alan Michaels and the introductory review papers specially commissioned for the conference. Within each part of this book the review paper is followed by the contributed papers grouped alphabetically by their first author. All the original papers published here were accepted for publication after scientific refereeing.

One major concern of biotechnology is either using enzymes or producing them. Enzyme/protein production is therefore an important starting point for biotechnology. Bioseparation or Downstream Processing constitutes about 40-90% of the total production cost. Driven by economics, highly selective technologies applicable to large-scale processing have emerged during the last decade. These technologies are slowly diffusing to enzymologists who are working on a smaller scale, looking for fast and efficient purification protocols. The affinity-based techniques (including precipitation, two-phase extractions, expanded bed chromatography, perfusion chromatography and monoliths) described in this volume provide current and new cutting-edge methods. Consequently, the book is of main interest to researchers in biochemistry, biochemical engineering and biotechnology, working either in academic or industrial sectors.

This text details the relationship between membrane technology and bioprocesses, discussing applications. This second edition refines and optimizes key features of the first edition - and features new illustrative case studies. The book examines advantages and disadvantages of using standard and new membrane technologies; analyzes a wide range of a

This book reviews methods and techniques for separating food components and products of the biotechnology industry. The introduction focuses on food composition and some of the conventional separation techniques. Subsequent chapters deal with each specific type or area of application individually and include information on the basic principles, industrial equipment available, commercial applications and an overview of research and development.

Edited to avoid duplication and favor comprehensiveness, 20 contributors detail the recovery, separation, and purification operations of bioprocess technology. Individual chapters in this classic yet still highly relevant work emphasize concepts that are becoming more and more important when applied to the large scale versions of techniques that are considered well established. Aside from fully discussing processes, Separation Processes in Biotechnology includes sections on concentration separation and operation, purification operations, and product release and recovery. It also discusses plant operation and equipment and delves into economic considerations