Triglycerides, lipase-catalyzed interesterification

The reaction of interesterification consists of an exchange of the carboxylate moiety of an ester and can be realized by reaction of an ester with a free acid (acidolysis) or reaction of two esters (Scheme 2). The interesterification process typically occurs among triglycerides and is often catalyzed by lipases [66,67]. As an example of a useful lipase-catalyzed interesterification, it has been reported (Scheme 3) that the exchange of butanoic acid in tributyrin with a polyunsaturated fatty acid may be carried out without solvent in the presence of Candida antarctica lipase [68]. 

T Adshiri, H Akiya, LC Chin, K Aral, K Fujimoto. Lipase-catalyzed interesterification of triglyceride with supercritical carbon dioxide extraction. J Chem Eng of Japan 25 104-105,... 

Michor, H. Marr, R. Gamse, T. Schilling, T. Klingsbichel, E. Schwab, H. Enzymatic Catalysis in Supercritical Carbon Dioxide Comparison of Different Lipases and a Novel Esterase. Biotechnol. Lett. 1996b, 18, 79-84. Miller, D. A. Blanch, H. W. Prausnitz, J. M. Enzyme-Catalyzed Interesterification of Triglycerides in Supercritical Carbon Dioxide. Ind. Eng. Chem. Res. 1991, 30, 939-946. 

Kalo, P., Parviainen, P., Vaara, K., Ali-Yrrko, S., Antila, M. 1986a. Changes in the triglyceride composition of butter fat induced by lipase and sodium methoxide catalyzed interesterification reactions. Milchwissenschaft 41, 82-85. 

In the interesterification of fats, 1,3-positional specific lipases catalyze reactions in which only the fatty acids in the a-positions of the triglycerides take part, whereas positional nonspecific lipases are able to catalyze reactions in which the fatty acids from both the a- and / -positions take part. In transesterification between two types of fat, the positional non-specific lipase is therefore able to randomize the fatty acids, resulting in the same fatty acid composition in the triglycerides as obtained in the commercially important chemical randomization process. In ester synthesis, positional non-specific lipases catalyze the reaction with both primary and secondary alcohols whereas positional specific lipases are more or less specific for primary alcohols. 

Again, the use of lipase catalyst for interesterification of edible fats and oils has advantages over the classical chemical catalysts. One of the most attractive features is the unique specificities possible with their use. Nonspecific lipases provide reactions like the random chemical catalyzed interesterification. Specific lipases make it possible to produce fats and oils with a customized triglyceride structure. The enzymatic process can be selective with the use of a positional specificity lipase. These processes are usually much slower and more sensitive to the reaction conditions to provide a better control over the reaction results. Also, the lipases can operate under milder reaction conditions, temperature and pressure, that minimize the formation of side products. 

Commercial laccase was immobilized onto a spiral-wound asymmetric polyethersulfone membrane. The laccase membrane reactor was applied to the biodegradation of a model phenol solution. The feasibility of using a hollow-fiber membrane reactor for the Upase-catalyzed interesterification reaction of triglycerides and fatty acids in a micro aqueous n-hexane system was developed by Basheer et al. In this case they use a stirred-tank reactor as well as a hollow-fiber membrane reactor system. Moreover, in 2004 a new immobilization of lipase into microporous... 

SCFs offer a nonaqueous environment which can be desirable for enzymatic catalysis of lipophilic substrates. The lipophilic substance cholesterol is 2 to 3 orders of magnitude more soluble in CX>2-cosolvent blends than in waterQ). In CO2 based blends, it may be oxidized to cholest-4en-3one, a precursor for pharmaceutical production using an immobilized enzyim(22). The enzyme polyphenol oxidase has been found to be catalytically active in supercritical CO2 and fluoroform (22). The purpose of using a SCF is that it is miscible with one of the reactants-oxygen. Lipase may be used to catalyze the hydrolysis and interesterification of triglycerides in supercritical OO2 without severe loss of activity(24). These reactions could be integrated with SCF separations for product recovery. 

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