Microbial Polyesters

This is the first book to present a topical overview of the research and development of microbial polyesters. Comprehensive and amply illustrated, it covers the * biosynthesis * structure * properties * applications of these biodegradable and biocompatible thermoplastics. The book provides the reader with the necessary background to understand the nature and mechanism of biological polymerization. It unites aspects from both the biological and polymer sciences and is a typical modern example of the analysis of biological macromolecules.

This book details polysaccharides and other important biomacromolecules covering their source, production, structures, properties, and current and potential application in the fields of biotechnology and medicine. It includes a systematic discussion on the general strategies of isolation, separation and characterization of polysaccharides and proteins. Subsequent chapters are devoted to polysaccharides obtained from various sources, including botanical, algal, animal and microbial. In the area of botanical polysaccharides, separate chapters are devoted to the sources, structure, properties and medical applications of cellulose and its derivatives, starch and its derivatives, pectins, and exudate gums, notably gum arabic. Another chapter discusses the potential of hemicelluloses (xylans and xylan derivatives) as a new source of functional biopolymers for biomedical and industrial applications. The algal polysaccharide, alginate, has significant application in food, pharmaceuticals and the medical field, all of which are reviewed in a separate chapter. Polysaccharides of animal origin are included with separate chapters on the sources, production, biocompatibility, biodegradability and biomedical applications of chitin (chitosan) and hyaluronan. With the increasing knowledge and applications of genetic engineering there is also an introduction in the book to nucleic acid polymers, the genome research and genetic engineering. Proteins and protein conjugates are covered, with one chapter providing a general review of structural glycoproteins, fibronectin and laminin, together with their role in the promotion of cell adhesion in vascular grafts, implants and tissue engineering. Another chapter discusses general aspects of a number of industrial proteins, including casein, caseinates, whey protein, gluten and soy proteins, with emphasis on their medical applications, and with reference to the potential of bacterial proteins. Another natural polymer resource, microbial polyesters, although small compared with polysaccharides and proteins, is also gaining increasing interest in biomedical technology and other industrial sectors. One chapter, therefore, is devoted to microbial polyesters, with comprehensive coverage of their biosynthesis, properties, enzymic degradation and applications. By dealing with biopolymers at the molecular level, the book is aimed at the biomedical and wider materials science communities and provides an advanced overview of biopolymers at the graduate and postgraduate level. In addition it will appeal to both academic and industrial life scientists who are involved in research and development activities in the medical and biotechnology field.

Our interest in the microbial biodegradation of xenobiotics has increased many folds in recent years to find out sustainable ways for environmental cleanup. Bioremediation and biotransformation processes harness the naturally occurring ability of microbes to degrade, transform or accumulate a wide range of organic pollutants. Major methodological breakthroughs in recent years through detailed genomic, metagenomic, proteomic, bioinformatic and other high-throughput analyses of environmentally relevant microorganisms have provided us unprecedented insights into key biodegradative pathways and the ability of organisms to adapt to changing environmental conditions. The degradation of a wide spectrum of organic pollutants and wastes discharged into the environment by anthropogenic activities is an emerging need today to promote sustainable development of our society with low environmental impact. Microbial processes play a major role in the removal of recalcitrant compounds taking advantage of the astonishing catabolic versatility of microorganisms to degrade or transform such compounds. New breakthroughs in sequencing, genomics, proteomics, bioinformatics and imaging are generating vital information which opens a new era providing new insights of metabolic and regulatory networks, as well as clues to the evolution of degradation pathways and to the molecular adaptation strategies to changing environmental conditions. Functional genomic and metagenomic approaches are increasing our understanding of the relative importance of different pathways and regulatory networks to carbon flux in particular environments and for particular compounds. New approaches will certainly accelerate the development of bioremediation technologies and biotransformation processes in coming years for natural attenuation of contaminated environments

Global plastic production is estimated to be over 300Mt annually. Most conventional plastics are predominantly produced from fossil fuels and are highly resistant to biodegradation, and only a small share of about 20% of spent plastics is believed to be recycled, which is a cause for environmental concern. Biodegradable plastics would solve this concern as they are a sustainable alternative, yet these do not even cover 5% of the global plastic market. Microbial polyhydroxyalkanoates (PHAs) are a versatile group of polyesters produced by nature as prokaryotic storage materials. PHAs can be produced through sustainable bioprocess engineering and have displayed remarkable flexibility in their physical and chemical properties. PHAs are the subject of several scientific papers and numerous PHA patents have also been filed, generating significant interest in the plastic production industry. To develop overall sustainable and efficient production processes, all bioprocess steps need to be thoroughly understood and accounted for. These processes start with the selection of suitable inexpensive raw materials (microbes and enzymes), optimizing the process engineering and process regime, and conclude with the enhancement of product recovery in terms of time, energy, and material input. Microbial Biopolyester Production, Performance and Processing: Bioengineering, Characterization, and Sustainability is a compilation of eight chapters covering bacterial polyesters, green plastics and PHAs from various angles. The contents of this volume focus on sustainable practices focus on the sustainability of processes that involve the synthesis and recycling of these meterials. The volume is a useful resource for bioprocess engineers, microbiologists, biotechnologists and chemical engineers interested in the basics of biodegradable plastic production.

Telechelic polymers have garnered a great deal of scientific interest due to their reactive chain-end functions. This comprehensive book compiles and details the basic principles of and cutting-edge research in telechelic polyesters, polycarbonates, and polyethers, ranging from synthesis to applications. It discusses general strategies toward telechelic polymers, centered on the fundamental aspects of polycondensation reactions, of cationic, anionic, coordination-insertion, and activated monomer mechanisms of the metal-, enzyme-, or otherwise organocatalyzed ring-opening polymerization of cyclic monomers, and of postpolymerization chemical modification methods of polymer precursors. All main classes of polymers are covered separately, comprising polyhydroxyalkanoates, poly(ε-caprolactone)s, poly(lactic acid)s, polylactides, polycarobnates, and polyethers, including synthetic approaches as well as some illustrative, up-to-date examples and uses. The book also addresses applications of hydroxyl, thiol, amino, or acrylate/methacrylate end-capped polymers as starting materials for the preparation of diverse polymer architectures ranging from block, graft, and star-shaped polymers and micelles to precursors for ATRP macroinitiators, polyurethane copolymers, shape-memory polymers, or nanosized drug delivery systems. The book will appeal to advanced undergraduate- and graduate-level students of polymer science; researchers in macromolecular science, especially those with an interest in functional and reactive polymers; and polymer chemists in academia and industry.

Living systems synthesize seven different classes of polymers. They provide structure and form for cells and organisms, function as catalysts and energy storage and carry the genetic information. All these polymers possess technically interesting properties. Some of these biopolymers are already used commercially. This special volume of Advances in Biochemical Engineering/Biotechnology comprises 10 chapters. It gives an overview of the water insoluble biopolyesters, in particular of the microbially synthesized poly-hydroxyalkanoate (PHA) family. It reports the state of the art of metabolism, regulation and genetic background, the latest advances made in genetic optimization of bacteria, "construction" of transgenic plants and in vitro synthesis by means of purified enzymes. Furthermore, it describes relevant technologies and evaluates perspectives concerning increasing the economic viability and competitiveness of PHA and discusses applications in medicine, packaging, food and other fields.

This volume deals with "Microbial Production of L-Amino Acids" and presents five comprehensive, expert and actual review articles on the modern production of Amino Acids by application of biotechnologically optimized microorganisms. This includes not only the modern techniques of enzyme, metabolic and transport engineering but also sophisticated analytical methods like metabolic flux analysis and subsequent pathway modeling. A general review about industrial processes of Amino Acid production provides a comprehensive overview about recent strain development as well as fermentation technologies. It was our special interest to focus the other articles on the most important and best selling amino acids on the world market i.e. L-Glutamate, L-Lysine and L-Threonine. The authors of this special volume have contributed significantly to the progress of Amino Acid biotechnology in the last decades and earn our special gratitude and admiration for their expert review articles.