Enzymatic synthesis reactor

W. Berke, H. J. Schuz, C. Wandrey, M. Morr, G. Denda, and M. R. Kula, Continuous regeneration of ATP in enzyme membrane reactor for enzymatic synthesis, BiotechnoL Bioeng., 32, 130-139 (1988). 

Pfaar, U. Gygax, D. Gertsch, W. Winkler, T. Ghisalba, O. (1999) Enzymatic synthesis of p-D-glucuronides in an enzyme membrane reactor. Chimia, 53, 590-3. 

In 2002, Do et al. [85] proposed a pathway for the enzymatic synthesis of (-)-menthyl a-maltoside and a-maltooligosides from (-)-menthyl a-glucoside using cyclodextrin glucanotransferase obtained from Bacillus macerans. The reaction can be performed in a reactor containing (-)-menthyl a-glucoside, the enzyme and soluble starch the yield was about 80% 15% (-)-menthyl a-malto-side and 65% (-)-menthyl a-maltooligosides, respectively. Treatment of the starch with a-amylase can raise the proportion of (-)-menthyl a-maltoside. 

Enzyme techniques are primarily developed for commercial reasons, and so information about immobilization and process conditions is usually limited. A commercially available immobilized penicillin V acylase is made by glutaraldehyde cross-linking of a cell homogenate. It can be used in batch stirred tank or recycled packed-bed reactors with typical operating parameters as indicated in Table 2 (38). Further development may lead to the creation of acylases and processes that can also be used for attaching side chains by enzymatic synthesis. 

Fig. 19. Enzymatic synthesis of dTDP-Glc (27) with sucrose synthase in an optimized batch and an enzyme membrane reactor [284]...

Recent studies in the pharmaceutical field using MBR technology are related to optical resolution of racemic mixtures or esters synthesis. The kinetic resolution of (R,S)-naproxen methyl esters to produce (S)-naproxen in emulsion enzyme membrane reactors (E-EMRs) where emulsion is produced by crossflow membrane emulsification [38, 39], and of racemic ibuprofen ester [40] were developed. The esters synthesis, like for example butyl laurate, by a covalent attachment of Candida antarctica lipase B (CALB) onto a ceramic support previously coated by polymers was recently described [41]. An enzymatic membrane reactor based on the immobilization of lipase on a ceramic support was used to perform interesterification between castor oil triglycerides and methyl oleate, reducing the viscosity of the substrate by injecting supercritical CO2 [42],... 

Enzymatic synthesis of E-tm-leucine is another example of the use of isolated enzymes (Bommarius et al, 1995). An NADH-dependent leucine dehydrogenase was used as a catalyst for the reductive amination of the corresponding keto acid together with formate dehydrogenase (FDH) and formate as a cofactor regenerator (Fig. 19.5b Shaked and Whitesides, 1980 Wichmann et al, 1981). Furthermore, a unique membrane reactor system involving FDH and PEG-modihed-NAD for continuous NADH regeneration... 

Ergezinger M, Bohnet M, Berensmeier S, Bucholz K (2006) Integrated enzymatic synthesis and adsorption of Isomaltose in a multiphase fluidized bed reactor. Eng Life Sci 5 1-8... 

Reaction performance. Supercritical carbon dioxide was used as a reaction media for the enzymatic synthesis of oleyl oleate directly from oleic acid and oleyl alcohol. Reaction was catalyzed by immobilized lipase from Rhizomucor miehei-Ltpozyme IM. Reactions were carried out in the high pressure batch and continuous reactor. 

Hernandez FJ, de los Rios AP, Gomez D, Rubio M, ViUora G. A new recirculating enzymatic membrane reactor for ester synthesis in ionic liquid/supercritical carbon dioxide biphasic systems. Appl Catal B 2006 67 121-126. 

Fig. 8.1 Experimental set-up of the recirculating enzymatic membrane reactor used for the synthesis of butyl propionate from vinyl propionate and 1-butanol catalysed by Candida antarctica lipase B in supercritical carbon dioxide and supercritical carbon dioxide/ionic liquid biphasic system [17]...

Hemdndez FJ, de los Rfos AP, Gomez D et al (2007) Understanding the chemical reaction and mass-transfer phenomena in a recirculating enzymatic membrane reactor for green ester synthesis in ionic Uquid/supercritical carbon dioxide biphasic systems. J Supercrit Flitids 43 303-309... 

In the following discussion the method of reactor optimization will be demonstrated using two enzyme systems introduced earlier, namely the enzymatic synthesis of N-acetylneuraminic acid and the enzymatic synthesis of cyanohydrins using oxynitrilase. 

The enzymatic synthesis reaction of l-DOPA is carried out in a batchwise system with cells of E. herbicola with high TPL activity. Since pyruvate, one of the substrates, was unstable in the reaction mixture at a high temperature, low temperature was favored for the synthesis of l-DOPA. The reaction was carried out at 16 °C for 48 h in a reaction mixture containing various amounts of sodium pyruvate, 5 g of ammonium acetate, 0.6 g of pyrocatechol, 0.2 g of sodium sulfite, 0.1 g of EDTA, and cells harvested from 100 ml of broth, in a total volume of 100 ml. The pH was adjusted to 8.0 by the addition of ammonia. At 2-h intervals, sodium pyruvate and pyrocatechol were added to the reaction mixture to maintain the initial concentrations. The maximum synthesis of l-DOPA was obtained when the concentration of sodium pyruvate was kept at 0.5%. The substrates, pyrocatechol and pyruvate, were added at intervals to prevent the denaturation of TPL and to prevent byproduct formation. The addition of sodium sulfite is effective in maintaining the reactor in a reductive state and in preventing the oxidation of the l-DOPA produced. l-DOPA is insoluble in the reaction medium, so it appears as a crystalline precipitate during the reaction, at final amounts reaching 110 g/1 [19-21]. 

Clapes P, Mata-Alvarez J, Valencia G et al. (1989) Continuous enzymatic synthesis of Z-kyotorphin amide in an enzyme-immobilized fixed-bed reactor. J Chem Technol Biotechnol 45 191-202 Clapes P, Adlercreutz P, Mattiasson B (1990a) Enzymatic peptide synthesis in organic media a comparative study of water-miscible and water-immiscible solvent systems. J Biotechnol 15(4) 323-338... 

Liquid-liquid-solid reactors are commonly used for biphasic reactions catalyzed by immobilized phase-transfer catalysts (which form the third, solid phase). Certain basic aspects of such reactors were considered in Chapter 19. Three-phase reactions of this type are also encountered in biological reactions, for example, the enzymatic synthesis of amino acid esters in polyphasic media (Vidaluc et al., 1983), and the production of L-phenylalanine utilizing enzymatic resolution in the presence of an organic solvent (Dahod and Empie, 1986). Predictably, the performance of these reactors is influenced by the usual kinetic and mass transfer aspects of heterogeneous systems (see Lilly, 1982 Chen et al., 1982 Woodley et al., 1991a,b). Additionally, performance is also influenced by the complex hydrodynamics associated with the flow of two liquids past a bed of solids (Mitarai and Kawakami, 1994 Huneke and Flaschel, 1998). It is noteworthy, for instance, that phase distribution within the reactor is different from that in the feed and is also a function of position within the reactor and within the voids of each pellet in the bed. More intensive research is needed before these reactors can be rationally designed. 

Figure 2. Schematic representation of the enzyme membrane reactor (EMR) system used for enzymatic synthesis of P-D>glucuronides.

Ebrahimi M, Placido L, Engel L, Ashaghi KS, and Czermak P. A novel ceramic membrane reactor system for the continuous enzymatic synthesis of oligosaccharides. Desalination 2010 250 1105-1108. 

Habnlin M, Knez Z, (1991), Enzymatic synthesis of n-bntyl oleate in a hollow fiber membrane reactor , / Membrane Sci., 61,315-324. 

Trusek-Holownia, A., Noworyta, A. (2007). An integrated process ester synthesis in an enzymatic membrane reactor and water sorption. Jourruil of Biotechnology, 130, 47—56. 

The reactor is normally associated with chemical processes, but work in the US is directed at developing enzymatic micro-reactors . It is believed that these could be used as sensors, for energy production, chemical synthesis and environmental clean-up. The inherent advantage of enzymes in reactors is that they operate at ambient temperatures and pressures. This, of course, potentially leads to less complex engineering than that necessary for most chemical micro-reactors. 

Hernandez, F. J., A. P. de los Rfos, D. Gomez, M. Rubio, and G. Vfllora. 2006. A New Recirculating Enzymatic Membrane Reactor for Ester Synthesis in Ionic Liquid/ Supercritical Carbon Dioxide Biphasic Systems. Applied Catalysis B Environmental Cl (1-2) 121-126. 

Akacha, N.B. and Gargouri, M. (2009) Enzymatic synthesis of green notes with hydroperoxide-lyase from olive leaves and alcohol-dehydrogenase from yeast in liquid/gas reactor. Process Biochem., 44, 1122-1127. 

Eujii, M., Rapid enzymatic transclyco-sflation and oligosaccharide synthesis in a microchip reactor. Lab. Chip 2 (2002)... 

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