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Advantages, drawbacks and trends in nanomaterials for enzyme immobilization.

Different core-shell polymeric supports, exhibiting different morphologies and composition, were produced through simultaneous suspension and emulsion polymerization, using styrene (S) and divinylbenzene (DVB) as co-monomers. Supports composed of polystyrene in both the core and the shell (PS/PS) and the new poly(styrene-co-divinylbenzene) support (PS-co-DVB/PS-co-DVB) were used for the immobilization of three different lipases (from Rhizomucor miehie (RML), from Themomyces lanuginosus (TLL) and the form B from Candida antarctica, (CALB)) and of the phospholipase Lecitase Ultra (LU). The features of the new biocatalysts were evaluated and compared to the properties of commercial biocatalysts (Novozym 435 (CALB), Lipozyme RM IM and Lipozyme TL IM) and biocatalysts prepared by enzyme immobilization onto commercial octyl-agarose, a support reported as very suitable for lipase immobilization. It was shown that protein loading and stability of the biocatalysts prepared with the core-shell supports were higher than the ones obtained with commercial octyl-agarose or the commercial lipase preparations. Besides, it was shown that the biocatalysts prepared with the core-shell supports also presented higher activities than commercial biocatalysts when employing different substrates, encouraging the use of the produced core-shell supports for immobilization of lipases and the development of new applications.

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This paper shows the production of lipase B from Candida antarctica (LIPB) after cloning the gene that encoded it in Pichia pastoris using PGK as a constitutive promoter. The lipase was immobilized on different home-made supports for distinct reactions.

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A recombinant lipase B from Candida antarctica (LipB) in Pichia pastoris was synthesized through submerged fermentation using crude glycerin as substrate. The immobilization of this enzyme on the core–shell polymeric supports is an effective alternative for its application. The supports with distinct levels of hydrophobicity were produced through combined suspension and emulsion polymerization in pilot scale. Particles with distinct compositions were synthesized (PMMA/PMMA; PMMA‐co‐DVB/PMMA‐co‐DVB; and PS‐co‐DVB/PS‐co‐DVB) and employed on the immobilization of the produced lipase (LipB) and the commercial enzyme (CalB). The morphological properties (specific area, average pore diameter, specific volume of pores, and hydrophobicity level) and the influence of the polymerization conditions on the morphology of the supports were studied. The thermal stability of such biocatalysts was also investigated in the presence of calcium cation (Ca+2), maintained 100% of the activity after 3 h at 50°C when the PMMA‐co‐DVB/PMMA‐co‐DVB was employed. The synthesized enzyme and supports manufactured in pilot scale were employed successfully for production of esters using residual fatty acids as substrates, adding value to these raw materials and increasing the ranges of possible applications.