Biocatalysis, DESs solvents

In this volume not all stress types are treated. Various aspects have been reviewed recently by various authors e.g. The effects of oxygen on recombinant protein expression by Konz et al. [2]. The Mechanisms by which bacterial cells respond to pH was considered in a Symposium in 1999 [3] and solvent effects were reviewed by de Bont in the article Solvent-tolerant bacteria in biocatalysis [4]. Therefore, these aspects are not considered in this volume. Influence of fluid dynamical stresses on micro-organism, animal and plant cells are in center of interest in this volume. In chapter 2, H.-J. Henzler discusses the quantitative evaluation of fluid dynamical stresses in various type of reactors with different methods based on investigations performed on laboratory an pilot plant scales. S. S. Yim and A. Shamlou give a general review on the effects of fluid dynamical and mechanical stresses on micro-organisms and bio-polymers in chapter 3. G. Ketzmer describes the effects of shear stress on adherent cells in chapter 4. Finally, in chapter 5, P. Kieran considers the influence of stress on plant cells. 

Krieger N, Bhatnagar T, Baratti JC, Baron AM, De Lima VM, and Mitchell D. Non-aqueous biocatalysis in heterogeneous solvent systems. Food Technol. Biotechnol. 2004 42(4) 279-286. 

Biocatalysis in supercritical fluids, fluorous solvents, and under solvent-free conditions was recently reviewed (80). In this book, de Geus et al (17), Villarroya (41) and Bruns et al (32) all provide important examples of how supercritical CO2 can be used for enzyme-catalyzed reactions. Furthermore, Srienc et al (38) used ionic liquid media for enzyme-catalyzed polymerizations of p-butyrolactone in order to prepare poly(hydroxyalkanoic acids), PHA. The role of ionic liquids was to both maintain enzyme activity and propagating chain solubility so that high molecular weight products could be obtained in monophasic media. 

Earlier, we have described what is currently known about DES (and NADES), a new type of IL-related and potentially green solvent, its physicochemical properties, and its applications in biocatalysis and biotransformation. Although only in... 

In Chapter 25, Yang and Wen discussed the physicochemical properties of DESs and reviewed their uses as new reaction media for biocatalytic transformation, either as such or as a co-solvent with water. They have introduced a new type of DESs, natural DESs (NADESs), which possess an enormous potential for applications due to their non-toxicity, sustainability, and friendliness to the environment. The advantages of using DESs over the conventional ILs are low cost, easy preparation with high piuity and biodegradability, and low toxicity. More studies of DES on biocatalysis with the following perspectives have been suggested, (i) correlation between the stmctme and composition of a DES and its physicochemical properties (ii) correlation between the structure of a DES and its interaction with an enzyme and (iii) correlation between the DES structure and enzyme function. 

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