Lipases, large scale application

Two other immobilized enzymes have reached large scale industrial application penicillin amidase and lipase. 

There are several bulk industrial enzymes that are applied on a large scale, as outlined by Ward. Carbo-hydrases are used to process starches. Cellulase can convert cellulose, the largest component of biomass, into sugars that can be further converted into fuel ethanol via fermentation. Proteases have several industrial applications, particularly in the food processing industry. Lipases and lactases are used in several food processing applications as well. 

It has been shown that lipase-catalysed reactions can be used for fire large-scale production of modified tri ycerides. At present the technology is being targeted to the production of comparatively hig -value products such as confectionary fats. Wider application of file reactions to lower-value, higher-tonnage products will be dependent on the development of cheaper processes using more-productive and/or cheaper catalysts. 

A related selectivity-enhancing noncovalent modification of Candida rugosa lipase, which does not require tedious protein chromatography and which is therefore applicable to large-scale reactions is based on the treatment of crude CRL with 50% aqueous wo-propanol, which led (after simple centrifugation and dialysis) to a modified lipase preparation, which was not only more active, but also showed considerably enhanced enantioselectivity [424],... 

Kinetic inhibition experiments revealed that the molecular action of the base on the lipase is a noncompetitive inhibititm — i.e., the base attaches itself to the lipase at a site other than the active site - which inhibits the transformation of one enantiomer but not that of its mirror image. Moreover, the chirality of the base has only a marginal impact on the selectivity enhancement effect. The general applicability of this method - impeded by the high cost of morphinan alkaloids and their questionable use for large-scale synthesis — has been extended by the use of more simple amines such as N, A -dimethyl-4-methoxyphenethylamine (DMPA) [235]. 

Many enzyme solutions are commercially available, most notably proteases and lipases, some of which are sold in very large quantities. At small scales, transporting an enzyme solution under cold conditions is not an issue in most cases. On the other hand, transporting large amounts of relatively unstable enzyme solution over long distances can become a challenge when industrial-scale applications are considered. 

Until recently, these drawbacks limited the broader application of immobilized enzymes on industrial scales. Nowadays, large-scale production processes (10 -10 tons per year) using immobilized enzymes are practiced with a small number of enzymes such as lipase [10-12], lactase [13], penicillin G acylase [14], aspartase [15], and glucose isomerase [16], among others. DiCosimo and coworkers have recendy published an interesting review article on the industrial use of immobilized enzymes [5]. 

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