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1.
Appl Biochem Biotechnol ; 172(5): 2706-19, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24425303

RESUMO

The investigation on fabrication of Fe3O4-chitosan-pectinase nanobiocatalyst was performed by covalently binding the pectinase onto carboxyl group activated chitosan-coated magnetic nanoparticles (CMNPs). The morphological and size distribution analysis of the different magnetic nanoparticles (MNPs) was done using transmission electron microscopy (TEM), and the average diameter was 11.07 ± 3.04, 11.55 ± 3.16, and 11.59 ± 3.16 nm for MNPs, CMNPs, and fabricated nanobiocatalyst, respectively, suggesting that there was no significant change in the size of MNPs after coating and binding. The characteristic peaks occurred at 2θ of 30.39, 35.43, 43.37, 57.22, and 62.9, and their corresponding indices 220, 311, 400, 520, and 441 for different MNPs from the X-ray diffraction (XRD) studies confirmed the presence of Fe3O4 with the spinel structure, and there was no phase change even after coating and binding. The various required characteristic absorption peaks (575, 585, 1,563, 1,614, 1,651, and 1,653 cm(-1)) from Fourier transform infrared (FT-IR) spectroscopy confirmed the surface modifications and binding of pectinase onto the MNPs. At the weight ratio of about 19.8 × 10(-3) mg bound pectinase/mg activated CMNPs, the activity of fabricated nanobiocatalyst was found to be maximum. In order to monitor their improved activity, the pH, temperature, reusability, storage ability, and kinetic studies were established.


Assuntos
Quitosana/química , Enzimas Imobilizadas/química , Óxido Ferroso-Férrico/química , Nanopartículas de Magnetita/química , Poligalacturonase/química , Biocatálise , Ensaios Enzimáticos , Concentração de Íons de Hidrogênio , Cinética , Nanopartículas de Magnetita/ultraestrutura , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
2.
Mater Sci Eng C Mater Biol Appl ; 33(4): 2273-9, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23498258

RESUMO

The covalent binding of pectinase onto amino functionalized silica-coated magnetic nanoparticles (CSMNPs) through glutaraldehyde activation was investigated for nanobiocatalyst fabrication. The average particle size and morphology of the nanoparticles were characterized using transmission electron microscopy (TEM). The statistical analysis for TEM image suggests that the coating and binding process did not cause any significant change in size of MNPs. The morphological and phase change of the magnetic nanoparticles (MNPs) after various coatings and immobilization were characterized by X-ray diffraction (XRD) studies. The various surface modifications and pectinase binding onto nanoparticles were confirmed by Fourier transform infrared (FT-IR) spectroscopy. The maximum activity of immobilized pectinase was obtained at its weight ratio of 19.0×10(-3) mg bound pectinase/mg CSMNPs. The pH, temperature, reusability, storage ability and kinetic studies were established to monitor their improved stability and activity of the fabricated nanobiocatalyst. Furthermore, the application was extended in the clarification of Malus domestica juice.


Assuntos
Biocatálise , Óxido Ferroso-Férrico/química , Nanopartículas/química , Nanotecnologia/métodos , Pectinas/metabolismo , Poligalacturonase/metabolismo , Dióxido de Silício/química , Bebidas , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Nanopartículas de Magnetita/ultraestrutura , Malus/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Reciclagem , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
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