title: Differential properties of Aspergillus niger tannase produced under solid-state and submerged fermentations.
abstract: Significant differences on structure, stability, and catalytic properties of tannase were found when this enzyme was produced under solid-state and submerged fermentations (SSF and SmF) by Aspergillus niger. The specific activity was 5.5 times higher on SSF than in SmF. Significant differences in isoelectric points of tannases were found. The pH optima for both types of enzyme was found at 6 and the pH stability of SSF and SmF tannase were at 6 and 5-8, respectively. The optimal temperature range was from 50 to 60 °C for SmF tannase and 60 °C for SSF tannase, and both enzyme types showed tolerance to high temperatures (60-70 °C). The SSF tannase showed a major specificity for methyl gallate substrate while SmF tannase for tannic acid. All metal ions tested, had an activity inhibition from 30-46% on SSF tannase. SDS-PAGE analysis as well as gel localization studies of both SSF and SmF purified tannases showed a single band with a molecular weight of 102 and 105 kDa, respectively. Different levels of glycosylation were found among SSF and SmF purified tannases. This is the first report about structural differences among tannase produced under SSF and SmF and this study provides basis for explanation of the stability and catalytic differences observed previously for this two tannase types.
authors.affiliation: Food Research Department, School of Chemistry, Universidad Autónoma de Coahuila, Blvd. V. Carranza and González Lobo, ZIP 25280, Saltillo, Coahuila, Mexico.
authors.forename: Jaqueline
authors.initials: J
authors.lastname: Renovato
authors.forename: Gerardo
authors.initials: G
authors.lastname: Gutiérrez-Sánchez
authors.forename: Luis V
authors.initials: LV
authors.lastname: Rodríguez-Durán
authors.forename: Carl
authors.initials: C
authors.lastname: Bergman
authors.forename: Raúl
authors.initials: R
authors.lastname: Rodríguez
authors.forename: Cristóbal Noe
authors.initials: CN
authors.lastname: Aguilar
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology* / Q000378:metabolism*; D002265:Carboxylic Ester Hydrolases / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D005285:Fermentation / Q000502:physiology; D006863:Hydrogen-Ion Concentration; D013696:Temperature
chemical_list: D002265:Carboxylic Ester Hydrolases; C022711:tannase