title: Immobilized lysozyme for the continuous lysis of lactic bacteria in wine: Bench-scale fluidized-bed reactor study.
abstract: Lysozyme from hen egg white (HEWL) was covalently immobilized on spherical supports based on microbial chitosan in order to develop a system for the continuous, efficient and food-grade enzymatic lysis of lactic bacteria (Oenococcus oeni) in white and red wine. The objective is to limit the sulfur dioxide dosage required to control malolactic fermentation, via a cell concentration typical during this process. The immobilization procedure was optimized in batch mode, evaluating the enzyme loading, the specific activity, and the kinetic parameters in model wine. Subsequently, a bench-scale fluidized-bed reactor was developed, applying the optimized process conditions. HEWL appeared more effective in the immobilized form than in the free one, when the reactor was applied in real white and red wine. This preliminary study suggests that covalent immobilization renders the enzyme less sensitive to the inhibitory effect of wine flavans.
authors.affiliation: Dept. for Innovation in Biological, Agro-food and Forest systems, University of Tuscia, Via S. Camillo de Lellis, 01100 Viterbo, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Cappannella
authors.affiliation: Dept. for Innovation in Biological, Agro-food and Forest systems, University of Tuscia, Via S. Camillo de Lellis, 01100 Viterbo, Italy. Electronic address: ilaria.be@tiscali.it.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Benucci
authors.affiliation: Dept. for Innovation in Biological, Agro-food and Forest systems, University of Tuscia, Via S. Camillo de Lellis, 01100 Viterbo, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Lombardelli
authors.affiliation: Dept. for Innovation in Biological, Agro-food and Forest systems, University of Tuscia, Via S. Camillo de Lellis, 01100 Viterbo, Italy.
authors.forename: Katia
authors.initials: K
authors.lastname: Liburdi
authors.affiliation: Department of Drug Sciences and Italian Biocatalysis Center, University of Pavia, via Taramelli 12, I-27100 Pavia, Italy.
authors.forename: Teodora
authors.initials: T
authors.lastname: Bavaro
authors.affiliation: Dept. for Innovation in Biological, Agro-food and Forest systems, University of Tuscia, Via S. Camillo de Lellis, 01100 Viterbo, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Esti
mesh_terms: D000818:Animals; D002645:Chickens / Q000378:metabolism; D005260:Female; D005285:Fermentation; D009113:Muramidase / Q000378:metabolism*; D056585:Oenococcus / Q000378:metabolism*; D013458:Sulfur Dioxide; D014920:Wine / Q000032:analysis*
chemical_list: D013458:Sulfur Dioxide; D009113:Muramidase
keywords: Antimicrobial activity; Fluidized bed reactor; Hen egg white lysozyme; Microbial chitosan; Red wine; White wine