Characterization of Mucor miehei lipase immobilized on polysiloxane-polyvinyl alcohol magnetic particles

Abstract

Mucor miehei lipase was immobilized on magnetic polysiloxane-polyvinyl alcohol particles by covalent binding. The resulting immobilized biocatalyst was recycled by seven assays, with a retained activity around 10% of its initial activity. K m and V max were respectively 228.3 lM and 36.1 U mg of protein )1 for immobilized enzyme. Whereas the optimum temperature remained the same for both soluble and immobilized lipase (45°C), there was a shift in pH profiles after immobilization. Optimum pH for the immobilized lipase was 8.0. Immobilized enzyme showed to be more resistant than soluble lipase when assays were performed out of the optimum temperature or pH.

Comparação do desempenho da lipase de candida rugosa imobilizada em suporte híbrido de polissiloxano-polivinilálcool empregando diferentes metodologias

“…O composto híbrido de POS-PVA foi sintetizado, conforme metodologia descrita por Bruno et al 15 , de acordo com as etapas a seguir descritas: I. Uma mistura de 50 mL de tetraetil ortossilicato (TEOS), 50 mL de etanol, 60 mL de uma solução aquosa de álcool polivinílico a 2% (m/v) e trinta gotas de HCl concentrado, foi aquecida a 60 °C, sob agitação, durante 40 min. II.…”

“…Recentemente foi testada com sucesso uma matriz híbrida constituída de polissiloxano-álcool polivinílico (POS-PVA) para imobilização de diferentes fontes de lipase: Mucor miehei 14,15 , pancreática 16,17 e Candida antarctica 18 . Essa matriz combina os atributos físico-químicos de materiais inorgânicos e orgânicos, permitindo a manipulação da hidrofilicidade e hidrofobicidade, condutividade elétrica, carga iônica, porosidade e propriedades mecânicas em geral 10,14 , bem como elevada atividade e estabilidade.…”

“…Este trabalho complementa os estudos anteriormente desenvolvidos [14][15][16][17][18] dando ênfase na utilização dessa matriz para imobilização da lipase de Candida rugosa. O objetivo foi comparar a eficiência de diferentes métodos de imobilização (Adsorção Física, Ligação Covalente e Encapsulação) na obtenção de sistemas imobilizados ativos e estáveis para subseqüente aplicação na síntese e hidrólise de ésteres.…”

Enzymatic synthesis of glyceride esters in solvent-free system: influence of the molar ratio, lipase source and functional activating agent of the support

“…2 The reagents TEOS (5 mL), ethanol (5 mL), and PVA solution 2% (m/v) (6 mL) were carefully mixed and stirred for 5 min at 60 ºC, followed by addition of two or three drops of concentrated HCl, in order to catalyze the reaction. After an incubation period of 40 min, the material was transferred to micro wells of tissue culture plates (disc shape) and kept at 25 ºC until complete gel solidification (formation of the interpenetrated network of POS-PVA).…”

“…1 Therefore, the need for developing active and stable immobilized biocatalysts for subsequent use in biotransformations has been highlighted. 2 Among the most important biocatalysts carrying out novel reactions in both aqueous and non aqueous media, lipases stand out due to their ability to utilize a wide spectrum of substrates, high stability towards extremes of temperature, pH and organic solvents, and chemo-, regio-and enantioselectivity. [3][4][5] Although most enzymatic syntheses are performed in presence of organic non-polar solvents, 6 the elimination of these compounds is technically feasible and offers significant cost savings.…”