title: Fouling-induced enzyme immobilization for membrane reactors.
abstract: A simple enzyme immobilization method accomplished by promoting membrane fouling formation is proposed. The immobilization method is based on adsorption and entrapment of the enzymes in/on the membrane. To evaluate the concept, two membrane orientations, skin layer facing feed (normal mode) and support layer facing feed (reverse mode), were used to immobilize alcohol dehydrogenase (ADH, EC 1.1.1.1) and glutamate dehydrogenase (GDH, EC 1.4.1.3), respectively. The nature of the fouling in each mode was determined by filtration fouling models. The permeate flux was larger in the normal mode, but the reverse mode allowed for higher enzyme loading and stability, and irreversible fouling (i.e. pore blocking) developed more readily in the support structure than in the skin layer. Compared with an enzymatic membrane reactor (EMR) with free enzymes, the novel EMR with enzymes immobilized in membrane support improved the enzyme reusability (especially for ADH), and reduced the product inhibition (especially for GDH).
authors.affiliation: Department of Chemical and Biochemical Engineering, Center for BioProcess Engineering, Technical University of Denmark, Building 229, DK-2800 Kgs. Lyngby, Denmark. Electronic address: Jluo@kt.dtu.dk.
authors.forename: Jianquan
authors.initials: J
authors.lastname: Luo
authors.affiliation: Department of Chemical and Biochemical Engineering, Center for BioProcess Engineering, Technical University of Denmark, Building 229, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Anne S
authors.initials: AS
authors.lastname: Meyer
authors.affiliation: Department of Chemical and Biochemical Engineering, Center for BioProcess Engineering, Technical University of Denmark, Building 229, DK-2800 Kgs. Lyngby, Denmark.
authors.forename: Gunnar
authors.initials: G
authors.lastname: Jonsson
authors.affiliation: Department of Chemical and Biochemical Engineering, Center for BioProcess Engineering, Technical University of Denmark, Building 229, DK-2800 Kgs. Lyngby, Denmark. Electronic address: mp@kt.dtu.dk.
authors.forename: Manuel
authors.initials: M
authors.lastname: Pinelo
mesh_terms: D000426:Alcohol Dehydrogenase / Q000378:metabolism*; D019149:Bioreactors; D004800:Enzymes, Immobilized / Q000378:metabolism*; D005969:Glutamate Dehydrogenase / Q000378:metabolism*; D008567:Membranes, Artificial
chemical_list: D004800:Enzymes, Immobilized; D008567:Membranes, Artificial; D000426:Alcohol Dehydrogenase; D005969:Glutamate Dehydrogenase
keywords: Biocatalysis; EMR; Enzyme immobilization; Protein; Ultrafiltration