TY - JOUR
T1 - Production of partially phosphorylated myo-inositol phosphates using phytases immobilised on magnetic nanoparticles
AU - Greiner, Ralf
AU - Konietzny, Ursula
AU - Blackburn, Daniel Menezes
AU - Jorquera, Milko A.
N1 - Funding Information:
This work was supported by the Co-Operative Project “Biotechnological Application of free and immobilised Phytases” funded by the German Federal Ministry for Education and Research (BMBF) and Comisión Nacional de Investigación Científica y Tecnológica de Chile (CONICYT), CHL 09/009.
PY - 2013/8
Y1 - 2013/8
N2 - Phytases of different origin were covalently bound onto Fe3O4 magnetic nanoparticles (12nm). Binding efficiencies of all three phytases were well above 70% relative to the number of aldehyde groups available on the surface of the magnetic nanoparticles. Temperature stability for all three phytases was enhanced as a consequence of immobilisation, whereas pH dependence of enzyme activity was not affected. Maximum catalytic activity of the immobilised phytases was found at 60°C (rye), 65°C (Aspergillus niger) and 70°C (Escherichia albertii). The immobilised enzymes exhibited the same excellent substrate specificities and unique myo-inositol phosphate phosphatase activities as their soluble counterparts. However, the catalytic turnover number dropped drastically for the immobilised phytases. The amount of the desired partially phosphorylated myo-inositol phosphate isomer could be easily controlled by the contact time of substrate solution and immobilised enzymes. The immobilised phytases showed a high operational stability by retaining almost full activity even after fifty uses.
AB - Phytases of different origin were covalently bound onto Fe3O4 magnetic nanoparticles (12nm). Binding efficiencies of all three phytases were well above 70% relative to the number of aldehyde groups available on the surface of the magnetic nanoparticles. Temperature stability for all three phytases was enhanced as a consequence of immobilisation, whereas pH dependence of enzyme activity was not affected. Maximum catalytic activity of the immobilised phytases was found at 60°C (rye), 65°C (Aspergillus niger) and 70°C (Escherichia albertii). The immobilised enzymes exhibited the same excellent substrate specificities and unique myo-inositol phosphate phosphatase activities as their soluble counterparts. However, the catalytic turnover number dropped drastically for the immobilised phytases. The amount of the desired partially phosphorylated myo-inositol phosphate isomer could be easily controlled by the contact time of substrate solution and immobilised enzymes. The immobilised phytases showed a high operational stability by retaining almost full activity even after fifty uses.
KW - Immobilisation
KW - Magnetic nanoparticles
KW - Myo-inositol phosphates
KW - Phytase
KW - Phytate
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U2 - 10.1016/j.biortech.2013.05.056
DO - 10.1016/j.biortech.2013.05.056
M3 - Article
AN - SCOPUS:84878781368
SN - 0960-8524
VL - 142
SP - 375
EP - 383
JO - Bioresource Technology
JF - Bioresource Technology
ER -