title: Characterization of a tannase from Emericella nidulans immobilized on ionic and covalent supports for propyl gallate synthesis.
abstract: The extracellular tannase from Emericela nidulans was immobilized on different ionic and covalent supports. The derivatives obtained using DEAE-Sepharose and Q-Sepharose were thermally stable from 60 to 75 °C, with a half life (t50) >24 h at 80 °C at pH 5.0. The glyoxyl-agarose and amino-glyoxyl derivatives showed a thermal stability which was lower than that observed for ionic supports. However, when the stability to pH was considered, the derivatives obtained from covalent supports were more stable than those obtained from ionic supports. DEAE-Sepharose and Q-Sepharose derivatives as well as the free enzyme were stable in 30 and 50 % (v/v) 1-propanol. The CNBr-agarose derivative catalyzed complete tannic acid hydrolysis, whereas the Q-Sepharose derivative catalyzed the transesterification reaction to produce propyl gallate (88 % recovery), which is an important antioxidant.
authors.affiliation: Instituto de Química de Araraquara - UNESP, Rua Prof. Francisco Degni s/n°, Araraquara 14800-000, Brazil.
authors.forename: Heloísa Bressan
authors.initials: HB
authors.lastname: Gonçalves
authors.forename: João Atílio
authors.initials: JA
authors.lastname: Jorge
authors.forename: Benevides Costa
authors.initials: BC
authors.lastname: Pessela
authors.forename: Glória Fernandez
authors.initials: GF
authors.lastname: Lorente
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Guisán
authors.forename: Luis Henrique Souza
authors.initials: LH
authors.lastname: Guimarães
mesh_terms: D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000378:metabolism*; D032842:Emericella / Q000201:enzymology*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D011435:Propyl Gallate / Q000378:metabolism*; D013634:Tannins / Q000378:metabolism; D013696:Temperature
chemical_list: D004800:Enzymes, Immobilized; D013634:Tannins; D011435:Propyl Gallate; D002265:Carboxylic Ester Hydrolases; C022711:tannase