Enzymatic production of alkyl esters through lipase-catalyzed transesterification reactions in organic solvents: Solvent effects and prediction capabilities of equilibrium conversions

Stamatis, H; Voutsas, EC; Delimitsou, C; Kolisis, FN; Tassios, D

dc.contributor.author	Stamatis, H	en
dc.contributor.author	Voutsas, EC	en
dc.contributor.author	Delimitsou, C	en
dc.contributor.author	Kolisis, FN	en
dc.contributor.author	Tassios, D	en
dc.date.accessioned	2014-03-01T01:15:35Z
dc.date.available	2014-03-01T01:15:35Z
dc.date.issued	2000	en
dc.identifier.issn	1024-2422	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/13616
dc.subject	transesterification	en
dc.subject	organic solvent	en
dc.subject	activity coefficient	en
dc.subject	UNIFAC	en
dc.subject.classification	Biochemistry & Molecular Biology	en
dc.subject.classification	Biotechnology & Applied Microbiology	en
dc.subject.other	UNIFAC GROUP-CONTRIBUTION	en
dc.subject.other	SYSTEMS	en
dc.subject.other	COEFFICIENTS	en
dc.subject.other	MEDIA	en
dc.subject.other	MODEL	en
dc.title	Enzymatic production of alkyl esters through lipase-catalyzed transesterification reactions in organic solvents: Solvent effects and prediction capabilities of equilibrium conversions	en
heal.type	journalArticle	en
heal.identifier.primary	10.3109/10242420009015249	en
heal.identifier.secondary	http://dx.doi.org/10.3109/10242420009015249	en
heal.language	English	en
heal.publicationDate	2000	en
heal.abstract	The solvent effect on the equilibrium position of the transesterification reaction of hexanol with ethyl acetate catalyzed by a lipase has been investigated in a variety of non-polar and polar solvents - and binary mixtures. The results obtained indicate that the solvent effect on the equilibrium conversion is very small as compared to that for the direct esterification reactions. Equilibrium conversions were then predicted using the equilibrium constant for the reaction obtained from Gibbs free energy of formation information for reactants and products in combination with the UNIFAC activity coefficient model. A solvent independent equilibrium conversion was obtained, which was in good agreement with the observed average value for all solvents. This indicates that UNIFAC provides satisfactory estimates of the activity coefficients but its group contribution structure does not allow the prediction of the small differences in conversion among the solvents examined. Finally plots of these conversions versus the solvent octanol/water partition coefficient or the solubility of water in the solvent, that provide the correct trend in direct esterification reactions, did not achieve the same for transesterification.	en
heal.publisher	HARWOOD ACAD PUBL GMBH	en
heal.journalName	BIOCATALYSIS AND BIOTRANSFORMATION	en
dc.identifier.doi	10.3109/10242420009015249	en
dc.identifier.isi	ISI:000088789200001	en
dc.identifier.volume	18	en
dc.identifier.issue	4	en
dc.identifier.spage	259	en
dc.identifier.epage	269	en