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Orientador(es)
Resumo(s)
This work aims at evaluating the potentialities of a heterologous Rhizopus oryzae lipase (rROL) as a feasible biocatalyst, to be used as an alternative to commercial lipases, for the synthesis of Human Milk Fat Substitutes (HMFS). This enzyme was immobilized in three different supports (Accurel® MP 1000, Eupergit® C and Lewatit® VP OC 1600) and tested as catalysts for the acidolysis between tripalmitin and oleic acid, batchwise, at 60 ◦C, in solvent-free medium.
The highest molar incorporations of oleic acid in the triacylglycerols were achieved with rROL in Lewatit® VP OC 1600 and Accurel® MP 1000, although the highest immobilization yields were observed with Eupergit® C.
Quasi-equilibrium was attained after 6 h or 12 h reaction, with about 30 mol.% and 22 mol.% of oleic acid incorporation, when rROL immobilized in Lewatit and Accurel were used, respectively.
Also, 23 h batch operational stability tests were performed: half-life times (t1/2) of 34.5 h and 64.0 h were achieved for rROL immobilized in Accurel® MP 1000 and in Lewatit® VP OC 1600, respectively. An important increase in the operational stability was observed for rROL immobilized in Lewatit after rehydration at the end of each batch (t1/2 = 202 h). Thus, the loss of activity may be explained by a progressive dehydration occurring along the reaction.
Descrição
Palavras-chave
Acidolysis Human milk fat substitutes Immobilization Recombinant lipase Rhizopus oryzae Operational stability
Contexto Educativo
Citação
Carla Tecelão, Marina Guillén, Francisco Valero, Suzana Ferreira-Dias, Immobilized heterologous Rhizopus oryzae lipase: A feasible biocatalyst for the production of human milk fat substitutes, Biochemical Engineering Journal, Volume 67, 2012, Pages 104-110, ISSN 1369-703X, https://doi.org/10.1016/j.bej.2012.06.001.
Editora
Elsevier
