Stable and continuous long-term enzymatic reaction using an enzyme-nanofiber composite.
This study shows the preparation and application of enzyme-nanofiber composites for long-term stable operation. The enzyme-nanofiber composite was prepared by coating an enzyme aggregate, the esterase from Rhizopus oryzae, on the surface of the nanofibers. After immobilization on the nanofiber, the apparent K ( m ) for the immobilized esterase was 1.48-fold higher than that of the free esterase, with values of 0.98 and 1.35 mM for the free and immobilized enzymes, respectively. It was found that enzyme-nanofiber was very stable, even when the fibers were shaken in glass vials, preserving 80% of the initial activity for 100 days. In addition, the enzyme-nanofiber composite was used repeatedly in 30 cycles of substrate hydrolysis and still remained active. Consequently, the esterase-nanofiber composite was employed within a continuous reactor system to evaluate its use in a long-term and stable continuous substrate hydrolysis reaction. It was found that the production of p-nitrophenol was stable for at least 400 h. This study demonstrates that the enzyme-nanofiber composite can be used in both repeated-batch mode and a continuous mode for a long-term stable operation.
Lee
Jin Hyung
JH
Advanced Environmental Monitoring Research Center (ADEMRC), Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea.
Hwang
Ee Taek
ET
Kim
Byoung Chan
BC
Lee
Sun-Mi
SM
Sang
Byoung-In
BI
Choi
Yong Su
YS
Kim
Jungbae
J
Gu
Man Bock
MB
D019149:Bioreactors; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000502:physiology*; D004950:Esterases / Q000502:physiology*; D008298:Maleates; D049329:Nanostructures; D011137:Polystyrenes; D012233:Rhizopus / Q000201:enzymology
D004800:Enzymes, Immobilized; D008298:Maleates; D011137:Polystyrenes; C521900:poly(styrene-co-maleic anhydride); D004950:Esterases