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Recently, significant efforts have been devoted into the study of the effect of hydrophobic supports on the catalytic properties of immobilized lipases. It seems that immobilization lipases on hydrophobic supports is a simple and efficient method to improve the catalytic activity of lipases. In this study, the hydrophobic poly(N-propyl-norbornene-exo-2,3-dicarboximide)s with well-controlled molecular weight were synthesized by the living ring-opening metathesis polymerization, and the lipases from Pseudo- monas sp. were then immobilized on these hydrophobic polymer supports through the physical ad- sorption. The immobilized lipases exhibited higher activity and enantioselectivity for the transesterifi- cation of 2-octanol than those of free lipases. Furthermore, we investigated the polymer molecular weight-mediated catalytic properties of immobilized lipases. It was found that the catalytic activity and E value of the immobilized lipases increased with the increase of the polymer molecular weight. At the polymeric molecular weight of about 40kDa, the highest E value (58 at 54.2% of conversion, enanti- omeric excess = 99%) was reached. After the molecular weight of polymers getting higher than 40 kDa, catalytic activity and E value of the immobilized lipase decreased.
Recently, significant efforts have been devoted into the study of the effect of hydrophobic of supports on the catalytic properties of immobilized lipases. It seems that immobilization lipases on hydrophobic supports is a simple and efficient method to improve the catalytic activity of lipases. In this study, the hydrophobic poly (N-propyl-norbornene-exo-2,3-dicarboximide) s with well-controlled molecular weight were synthesized by the living ring-opening metathesis polymerization, and the lipases from Pseudo- monas sp. were then immobilized on these hydrophobic polymer supports through the physical ad- sorption. The immobilized lipases exhibit higher activity and enantioselectivity for the transesterifi cation of 2-octanol than those of free lipases. Furthermore, we investigated the polymer molecular weight-mediated catalytic properties of immobilized lipases. It was found that the catalytic activity and E value of the immobilized lipases increased with the increase of the polymer molec At the molecular weight of polymers about 40 kDa, the highest E value (58 at 54.2% of conversion, enantiomeric o = 99%) was reached. After the molecular weight of polymers is higher than 40 kDa, catalytic activity and E value of the immobilized lipase decreased.