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FSB1 – 2004
Food Science and Biotechnology in Developing Countries
PRODUCTION AND STABILITY TO pH AND TEMPERATURE OF TANNASE FROM
Aspergillus niger GH1
Crystela Quintero Flores, Cristóbal Noé Aguilar*,
Raúl Rodríguez-Herrera and Juan CarlosvContreras-Esquivel.
Food Research Departament. School of Chemistry. Universidad Autónoma de Coahuila. Saltillo,
Coahuila, México. *Corresponding author, e-mail: cag13761@mail.uadec.mx
ABSTRACT
Tannase is an enzyme with a high potential for use in food industry. In this study, tannase from
Aspergillus niger GH1 was produced by solid state fermentation using polyurethane foam as support.
Enzyme was concentrated by dialysis and its stability to several values of pH and temperature was
evaluated. Time of tanase assay was also, studied. Obtained results demonstrated that this fungal
enzyme had an optimal pH of 5, an optimal temperature of 30ºC and a time of reaction of 10 minutes.
Keywords: tannase, stability, pH, temperature, solid state fermentation.
INTRODUCTIÓN
Tannase or tannin acyl hydrolase (E.C. 3.1.1.20), catalyzes the hydrolysis of ester bonds present in
hydrolysable tannins molecules like tannic acid and gallate esters. It is a glycoprotein formed by a
mixture of one esterase and one despídase Several studies carried out in submerged fermentation
have reported that it has a pH of stability between 3,5 - 8,0, an optimum pH of 5,5 - 6.0; the
temperature of stability is between 30 and 60°C, and the optimum value at 30 - 40°C; Its iso-electric
point is around 4,0 - 4.5; and the reported molecular weight varies de186 to 300 kDa, depending on the
source (Lekha and Lonsane, 1997; Aguilar and Gutierrez, 2001).
Tannase can be obtained from vegetal, animals and microbial sources. Last source is the way where
this enzymes is more stable, and the microorganisms can produce it in great amounts. The
microorganisms more studied are the filamentous fungi, between which are the strains of Ascochyta,
Aspergillus, Chaetomuum, Mucor, Neurospora, Rhizopus, Trichothercium and Penicillum. Tannase is
commercially used in the chemical, pharmaceutical, feed, drinks and foods industries. The main
commercial application of this enzyme is the hydrolysis of the gallotannins for gallic acid production, an
intermediary product required for the synthesis of the antibacterial drug trimethoprim (Belmares-Cerda
et al., 2004).
Aspergillus niger GH1 has been described as a fungal microorganism with a high potential to degrade
tannins. Tannase produced by this strain has been studied recently and preliminary studies on its
puritication have been recently described by Cruz-Hernández, (2004).
In this study, the objective was to evaluate the temperature and pH stability of the tannse produced by
A. niger GH1 in solid state fermentation. Also, time of enzyme reaction has been studied..