title: Immobilization of mycobacterial cells onto silicone--assessing the feasibility of the immobilized biocatalyst in the production of androstenedione from sitosterol.
abstract: Silicone rubbers are hydrophobic, a feature that may prove advantageous if this material is to be used as immobilization matrix in bioconversion systems where hydrophobic species are present, such as sterols and mycobacterial cells. Mycobacterium sp. cells with sitosterol side chain cleavage activity were accordingly effectively adsorbed onto silicone and the potential application of the concept was assessed by matching the behavior of the resulting immobilized biocatalyst with free cells and Celite immobilized cells. Mass transfer, kinetics, thermal and storage stability characterization of a biotransformation system based in the use of the silicone immobilized biocatalyst was performed. The feasibility of biocatalyst reutilization was tentatively explored.
authors.affiliation: Departamento de Engenharias e Ciências Naturais, Universidade Lusófona de Humanidades e Tecnologias, Av. Campo Grande 376, 1749-024 Lisboa, Portugal.
authors.forename: M J C
authors.initials: MJ
authors.lastname: Claudino
authors.forename: D
authors.initials: D
authors.lastname: Soares
authors.forename: F
authors.initials: F
authors.lastname: Van Keulen
authors.forename: M P C
authors.initials: MP
authors.lastname: Marques
authors.forename: J M S
authors.initials: JM
authors.lastname: Cabral
authors.forename: P
authors.initials: P
authors.lastname: Fernandes
mesh_terms: D000735:Androstenedione / Q000096:biosynthesis*; D001422:Bacterial Adhesion; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D005240:Feasibility Studies; D009161:Mycobacterium / Q000254:growth & development / Q000502:physiology; D012855:Sitosterols / Q000378:metabolism*
chemical_list: D012855:Sitosterols; D000735:Androstenedione; C025473:gamma-sitosterol