Specialty chemicals, production enzyme reaction

The production of both specialty and cammodlty chemicals by enzyme reaction has become a reality due to recent advances In Immobilization. These Immobilization techniques have provided an econcmlcal system for reuse of enzyme and thus provide a route to optical Iscmiers In high enantiomeric yields. This provides specific stereoisomers for agricultural synthesis at reasonable cost. The advantages of stereoisomers Include high activity levels as well as reduced toxicity due to the absence of the Incorrect stereoisomer. Methods of Immobilization will be reviewed with emphasis on Immobilization by polyazetldlne. Enzymatic reaction via immobilization enzymes and Immobilized whole cells will be reviewed with emphasis on the production of agrlcultaral chemicals. 

Chemical reactions enhanced by catalysts or enzymes are an integral part of the manufacturing processes for the majority of chemical products. The total market for catalysts and enzymes amounts to 11.5 billion (2005), of which catalysts account for about 80%. It consists of four main applications environment (e.g., automotive catalysts), 31% polymers (e.g., polyethylene and polypropylene), 24% petroleum processing (e.g., cracking and reforming), 23% and chemicals, 22%. Within the latter, particularly the catalysts and enzymes for chiral synthesis are noteworthy. Within catalysts, BINAPs [i.e., derivatives of 2,2 -bis(diphenylphosphino) -1, l -bis-l,l -binaphthyl) have made a great foray into chiral synthesis. Within enzymes, apart from bread-and-butter products, like lipases, nitrilases, acylases, lactamases, and esterases, there are products tailored for specific processes. These specialty enzymes improve the volumetric productivity 100-fold and more. Fine-chemical companies, which have an important captive use of enzymes, are offering them to third parties. Two examples are described here ... 

Microbes use enzymes as catalysts to obtain the desired or beneficial reaction and typically under mild conditions. The brewing of beer and fermentation of fruit and vegetable mass high in starches to produce consumable ethanol are the oldest and most familiar examples of using microbial action to achieve a desired end. But now much more has been demonstrated, from the production of essential human hormones to the synthesis of specialty chemicals. 

All biotechnological processes depend on enzymes - either in whole-cell living systems or isolated out of their biological context. In fact, purified enzymes are established in processing food and textiles and are supplements in feed and detergents - all products of everybody s daily life. Whole-cell systems particularly in the field of specialty chemicals provide a broad range of methods and processes. For many years, enantiomerically pure amino acids for food, feed and pharma industries have been produced by microbial fermentation. Ambitious R D resulted in enzymes especially modified and optimized for a desired chemical reaction such as biocatalysis of optically active amines, alcohols, epoxides and more. ... 

Flow reactors of aU shapes, sizes, and uses are encountered in aU phases of fife. Examples of interest to bioengineers include the pharmaceutical industry, to produce aspirin, penicfifin, and other drugs the biomass processing industry, to produce alcohol, enzymes and other specialty proteins, and value added products and the biotechnologically important tissue and cell culture systems. The type of reactor used depends on the specific application and on the scale desired. The choice is based on a number of factors. The primary ones are the reaction rate (or other rate-limiting process), the product distribution specifications, and the catalyst or other material characteristics, such as chemical and physical stability. 

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