%0 Journal Article
%A Abreu Silveira, Erick
%A Moreno-Pérez, Sonia
%A Basso, Alessandra
%A Serban, Simona
%A Pestana-Mamede, Rita
%A Tardioli, Paulo 
%A Farinas, Cristiane 
%A Castejón, Natalia
%A Fernández-Lorente, Gloria
%A Rocha Martín, Javier
%A Guisán, José 
%T Biocatalyst engineering of Thermomyces Lanuginosus lipase adsorbed on hydrophobic supports: Modulation of enzyme properties for ethanolysis of oil in solvent-free systems
%D 2018
%@ 0168-1656
%U https://hdl.handle.net/20.500.14352/94108
%X Different immobilized biocatalysts of Thermomyces lanuginosus lipase (TLL) exhibited different properties for the ethanolysis of high oleic sunflower oil in solvent-free systems. TLL immobilized by interfacial adsorption on octadecyl (C-18) supports lost its 1,3-regioselectivity and produced more than 99% of ethyl esters. This reaction was influenced by mass-transfer limitations. TLL adsorbed on macroporous C-18 supports (616 Å of pore diameter) was 10-fold more active than TLL adsorbed on mesoporous supports (100–200 Å of pore diameter) in solvent-free systems. Both derivatives exhibited similar activity when working in hexane in the absence of diffusional limitations. In addition, TLL adsorbed on macroporous Purolite C-18 was 5-fold more stable than TLL adsorbed on mesoporous Sepabeads C-18. The stability of the best biocatalyst was 20-fold lower in anhydrous oil than in anhydrous hexane. Mild PEGylation of immobilized TLL greatly increased its stability in anhydrous hexane at 40 °C, fully preserving the activity after 20 days. In anhydrous oil at 40 °C, PEGylated TLL-Purolite C-18 retained 65% of its initial activity after six days compared to 10% of the activity retained by the unmodified biocatalyst. Macroporous and highly hydrophobic supports (e.g., Purolite C-18) seem to be very useful to prepare optimal immobilized biocatalysts for ethanolysis of oils by TLL in solvent-free systems.
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