Biotechnology fine chemical reactions

For the application of membrane reactors it can be concluded that these are accepted as proven technology for many biotechnological apphcations. The membranes used in this area can operate under relatively mild conditions (low temperature and aqueous systems). However, there is a tremendous potential for membrane reactors in the chemical industry, which often requires apphcation in nonaqueous systems. Long term stability of the membrane materials in these systems will require an ongoing development from the side of materials scientists. As reaction selectivity is of major importance in the production of fine chemicals and pharmaceutical products, it seems plausible to expect that membrane reactors will find their way in the production of chemicals through applications in these areas. 

The monolithic stirrer reactor (MSR, Figure 2), in which monoliths are used as stirrer blades, is a new reactor type for heterogeneously catalyzed liquid and gas-liquid reactions (6). This reactor is thought to be especially useful in the production of fine chemicals and in biochemistry and biotechnology. In this work, we use cordierite monoliths as stirrer blades for enzyme-catalyzed reactions. Conventional enzyme carriers, including chitosan, polyethylenimine and different are used to functionalize the monoliths. Lipase was... 

Profile The company provides scientific information products and services to the fine-chemical, pharmaceutical, agrochemical, biotechnology, and academic research communities. Synopsys operates worldwide, with offices and distributors in Europe, the United States, and Japan. It specializes in chemical reaction databases that deliver added-value information and refined data. 

Since many enzymes have capacities to catalyze reactions with even unnatural substrates and to produce unnatural compounds, hybrid use of enzymes as biocatalysts with chemical synthesis can realize processes to produce useful substances with higher flexibility than processes with growing cells. Discovery of novel microbial enzymes with required specificity by screening is a key to the establishment of such a hybrid processes. Many successful achievements in Japan are observed in this unique field of biotechnology. Application of nitrile hydratase to production of acrylonitriles has proved that biocatalysts can be applied to production of commodity chemicals beyond the presumed limitation of fine chemicals. Discovery of the enzymatic reactions to produce trehalose from starch is an example that reveals the possibility of microbial screening or what remains undiscovered in the microbial world. The importance of developing new application is also crucial in this field as shown in the case of transglutaminase and alkaline cellulase. 

Chapter 3 is devoted to the topic of pervaporation membrane reactors. These are unique systems in that they use a liquid feed and a vacuum on the permeate side they also mostly utilize polymeric membranes. Chapter 4 presents a survey of membrane bioreactor processes these couple a biological reactor with a membrane process. Reactions studied in such systems include the broad class of fermentation-type or enzymatic processes, widely used in the biotechnology industry for the production of amino acids, antibiotics, and other fine chemicals. Similar membrane bioreactor systems are also fin-... 

Until now, microorganisms such as fungi and bacteria (often extremophiles) were used as main sources for enzymes. The growing complexity of reactions required for the production of fine chemicals, especially for the pharmaceutical industry, has increasingly drawn the attention of industrial biotechnology to plants. The high complexity of plants secondary metaboHsm, as well as the fact that most of today s small molecule drugs (SMDs) can be traced back to a plant metabolite as the basic structure, is certainly a major reason for this development Moreover,... 

Modern biotechnology, in combination with chemistry and process technology, is crucial for the development of new clean and cost effective mannfacturing concepts for fine-chemical, food specialty and pharmaceutical products. The impact of biocatalysis on the fine-chemicals industry is presented, where reduction of process development time, the number of reaction steps and the amount of waste generated per kg of end product are the main targets. Integration of biosynthesis and organic chemistry is seen as a key development. 

Extraction is often used in the fine-chemicals and biotechnology industry. Extraction technology has a number of distinct advantages (selectivity, capacity, robustness and good scalability), but an even longer list of disadvantages expensive solvent recovery, many practical problems such as emulsification and the mutual miscibility of solvent and water, solvent aging by oxidation and other chemical reactions, environmental and safety aspects because of toxicity, explo-sivity and flammability. 

Lonza, a fine chemical manufacturer, has developed a biotechnological route, starting with 3-cyanopyridine to nicotinamide (also known as niacin or vitamin B3) (see Fig. 9.11). Conversions are based on enzymatic hydrolysis with nitrile hydratase from Rhodo-coccus bacteria or by bioconversion with living bacterial cells. The reactions are very specific, and the yields are quantitative. Novo-zyme has introduced an extremely thermostable lipase from the yeast Candida (Pseudozyma) antarctica (Novozyme 435), which is extremely suitable for carrying out specific esterifications in organic solvents. 

Society is becoming progressively more worried with safety issues while wishing for a sustainable future. Sustainable chemistry represents an area of innovation, which not only preserves resources but also stands for a development process in the chemical industry. The most important goals in fine chemicals, skin care products and pharmaceuticals including biomedical compositions are the development of nontoxic and biodegradable compounds, the advance on new reaction conditions (cleaner solvents, biotechnological processes, etc.) and the use of raw materials from renewable feedstock [1]. 

TABLE 27.8 Examples of Reactions Developed and Carried Out by Lonza, One of the Pioneering Companies Using Biotechnology for Organic Chemical Synthesis of Fine Chemicals, Intermediates, and Pharmaceuticals [83]... 

In the case of basic chemicals the chances for new catalytic processes are small, but they are better for higher value chemicals such as fine and specialty chemicals. Pharmaceuticals and agrochemicals are two areas where homogeneous catalysts have advantages. Complex molecules can often be synthesized in single-step one-pot reactions with the aid of transition metals. This sector has many potential points of overlap with biotechnology, especially enzyme catalysis [5]. 

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