초록
<P><B>Abstract</B></P> <P>According to the purification characteristics of lipase from <I>Burkholderia ambifaria</I> YCJ01, mesoporous TiO<SUB>2</SUB> was functionalized by phenylaminopropyl trimethoxysilane (Ph-TiO<SUB>2</SUB>) for lipase immobilization. This support permitted one step immobilization and purification of lipase YCJ01 via hydrophobic interactions from crude fermentation supernatant. The activity of immobilized lipase was 6119.2U/g support with 12.8mg/g support of enzyme loading. The ratio of the activity of immobilized lipase to decrease activity in the supernatant after immobilization reached 2.2, which indicated that the immobilized lipase molecules exhibited a dramatic hyperactivation. In comparison with free lipase, immobilized lipase showed significantly improved pH stability and thermalstability. The Ph-TiO<SUB>2</SUB>/YCJ01 biocomposite was analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis. The result indicated lipase was efficiently immobilized on Ph-TiO<SUB>2</SUB> surface. Finally, the research about cinnamyl acetate synthesis suggested that Ph-TiO<SUB>2</SUB>/YCJ01 had enhanced catalytic efficiency compared with free lipase. In solvent free medium, the yield of 96.9% was obtained after one operation, and maintained more than 80% of yield after ten reaction cycles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Mesoporous TiO<SUB>2</SUB> was modified by phenylaminopropyl trimethoxysilane for microbial lipase immobilization. </LI> <LI> Lipase YCJ01 from fermentation culture was specifically immobilized on this support. </LI> <LI> Immobilized lipase showed a clear interfacial hyperactivation and enhanced stability. </LI> <LI> Efficient cinnamyl acetate yield of 96.9% by immobilized lipase was obtained in 6h. </LI> <LI> Immobilized lipase retained excellent operational stabilities after ten reuse cycles. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>