An, Hyo Jin Lee, Hye-Jin Jun, Seung-Hyun Hwang, Sang Youn Kim, Byoung Chan Kim, Kwanghee Lee, Kyung-Mi Oh, Min-Kyu Kim, Jungbae 2024-01-20T16:31:00Z 2024-01-20T16:31:00Z 2021-09-05 2011-09 1615-7591 https://pubs.kist.re.kr/handle/201004/130017 Lipase (LP) was immobilized on electrospun and ethanol-dispersed polystyrene-poly(styrene-co-maleic anhydride) (PS-PSMA) nanofibers (EtOH-NF) in the form of enzyme precipitate coatings (EPCs). LP precipitate coatings (EPCs-LP) were prepared in a three-step process, consisting of covalent attachment, LP precipitation, and crosslinking of precipitated LPs onto the covalently attached LPs via glutaraldehyde treatment. The LP precipitation was performed by adding various concentrations of ammonium sulfate (20-50%, w/v). EPCs-LP improved the LP activity and stability when compared to covalently attached LPs (CA-LP) and the enzyme coatings of LPs (EC-LP) without the LP precipitation. For example, the use of 40% (w/v) ammonium sulfate resulted in EPC40-LP with the highest activity, which was 4.0 and 3.6 times higher than those of CA-LP and EC-LP, respectively. After 165-day incubation under rigorous shaking at 200 rpm, the residual activities of EPC50-LP were 0.5 mu M/min mg of EtOH-NF, representing 113 and 75 times higher than those of CA-LP and EC-LP, respectively. When LP was partially purified via a simple ammonium sulfate precipitation and dialysis, both activities and stabilities of EC-LP and EPC-LP could be marginally improved. It is anticipated that the improved LP activity and stability in the form of EPCs would allow for their potential applications in various bioconversion processes such as biodiesel production and ibuprofen resolution. English SPRINGER WALLED CARBON NANOTUBES MESOPOROUS SILICA IMMOBILIZED ENZYMES CATALYTIC ACTIVITY PROTEIN DIGESTION BIOFUEL CELLS STABILITY NANOPARTICLES BIOCATALYSTS ELECTROSPUN Enzyme precipitate coatings of lipase on polymer nanofibers Article 10.1007/s00449-011-0534-y 1 BIOPROCESS AND BIOSYSTEMS ENGINEERING, v.34, no.7, pp.841 - 847 BIOPROCESS AND BIOSYSTEMS ENGINEERING 34 7 841 847 scie scopus 000293896200008 2-s2.0-81755168306 Biotechnology & Applied Microbiology Engineering, Chemical Biotechnology & Applied Microbiology Engineering Article WALLED CARBON NANOTUBES MESOPOROUS SILICA IMMOBILIZED ENZYMES CATALYTIC ACTIVITY PROTEIN DIGESTION BIOFUEL CELLS STABILITY NANOPARTICLES BIOCATALYSTS ELECTROSPUN Enzyme precipitate coatings Electrospun polymer nanofibers Ethanol dispersion Lipase Enzyme stabilization