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Lipase - catalyzed consecutive batch reaction for production of steryl esters from vegetable oil deodorizer distillates / A. R. S. Teixeira in Industrial & engineering chemistry research, Vol. 51 N° 15 (Avril 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 15 (Avril 2012) . - pp. 5443–5455 Titre : Lipase - catalyzed consecutive batch reaction for production of steryl esters from vegetable oil deodorizer distillates Type de document : texte imprimé Auteurs : A. R. S. Teixeira, Auteur ; J. L. C. Santos, Auteur ; J. G. Crespo, Auteur Année de publication : 2012 Article en page(s) : pp. 5443–5455 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Esterification  Vegetable  oil  deodorizer  distillates Résumé : A significant decrease of the yield of steryl esters production via the esterification of sterols and free fatty acids (FFA) present in vegetable oil deodorizer distillates was observed when consecutive batch reactions (24 hr each) were carried out using the same enzyme and under optimal operating conditions. The objective of this work is to identify the causes of such phenomena, in order to avoid or minimize it, allowing for reuse of the Candida rugosa lipase catalyst in consecutive batch reactions. The effect of water activity and glycerol produced by hydrolysis of acylglycerides, on the stability of the enzyme was studied. Results show that these effects were not the main reason for the decrease of yield in consecutive batch reactions. The presence of oxidation products proved to play an important role in the enzyme inactivation. Because of the high concentration of antioxidants (phenolic compounds, squalene, and tocopherols) naturally present in deodorizer distillates, the inactivation of the enzyme was minimized; nevertheless, it could not be avoided. A partial reuse of the enzyme is technically a possible solution, by adding fresh enzyme in the beginning of each batch reaction. Four consecutive batch reactions (24 hr each) were successfully carried out under optimal conditions, keeping a constant yield of steryl esters (SE) production (>85%). ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202853f [article] Lipase - catalyzed consecutive batch reaction for production of steryl esters from vegetable oil deodorizer distillates [texte imprimé] / A. R. S. Teixeira, Auteur ; J. L. C. Santos, Auteur ; J. G. Crespo, Auteur . - 2012 . - pp. 5443–5455. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 15 (Avril 2012) . - pp. 5443–5455 Mots-clés : Esterification  Vegetable  oil  deodorizer  distillates Résumé : A significant decrease of the yield of steryl esters production via the esterification of sterols and free fatty acids (FFA) present in vegetable oil deodorizer distillates was observed when consecutive batch reactions (24 hr each) were carried out using the same enzyme and under optimal operating conditions. The objective of this work is to identify the causes of such phenomena, in order to avoid or minimize it, allowing for reuse of the Candida rugosa lipase catalyst in consecutive batch reactions. The effect of water activity and glycerol produced by hydrolysis of acylglycerides, on the stability of the enzyme was studied. Results show that these effects were not the main reason for the decrease of yield in consecutive batch reactions. The presence of oxidation products proved to play an important role in the enzyme inactivation. Because of the high concentration of antioxidants (phenolic compounds, squalene, and tocopherols) naturally present in deodorizer distillates, the inactivation of the enzyme was minimized; nevertheless, it could not be avoided. A partial reuse of the enzyme is technically a possible solution, by adding fresh enzyme in the beginning of each batch reaction. Four consecutive batch reactions (24 hr each) were successfully carried out under optimal conditions, keeping a constant yield of steryl esters (SE) production (>85%). ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202853f