Characterization of a thermo-tolerant mycelial beta-fructofuranosidase from Aspergillus phoenicis under submerged fermentation using wheat bran as carbon source

Author(s)

Rustiguel, Cynthia Barbosa ^[1] ; Jorge, Joao Atilio ^[1] ; Souza Guimaraes, Luis Henrique ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Biol, Fac Filosofia Ciencias & Letras Ribeirao Preto, BR-14040901 Sao Paulo - Brazil

• Document type: Journal article
• Source: BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY; v. 4, n. 3, p. 362-369, JUL 2015.
• Web of Science Citations: 7

Abstract

The filamentous fungus Aspergillus phoenicis (Aspergillus saitoi) produced high levels of mycelial beta-D-fructofuranosidase (invertase) when cultivated under submerged fermentation using Khanna medium with wheat bran as the carbon source for 72 h at 40 degrees C, under orbital agitation (100 rpm). The mycelial invertase was purified 20-fold with 24% recovery through two chromatographic steps (DEAE-cellulose and Sephacryl S-200). The enzyme was characterized as a monomeric glycoprotein with 2% carbohydrate content and a native molecular mass of 131 kDa comprising two 70-kDa subunits. The optimal temperature and pH for activity were 65 degrees C and 4.5, respectively. The enzyme was resistant to temperatures of 50 degrees C. and 60 degrees C. and stable at pH 4.0-7.0. Activity increased in the presence of different ions, especially Mn2+ (+177 %), and Ag+ increased the invertase activity by 91%. The mycelial invertase hydrolyzed sucrose, raffinose, and inulin, with greater specificity for the former. The K-1/2 and V-max values for sucrose were 22.5 niM and 124.9 U mg(-1), respectively. (C) 2015 Elsevier Ltd. All rights reserved (AU)

• FAPESP's process: 09/01283-0 - Characterization of fructo-oligosacharides and b-fructosidases with biotechnological interest produced by filamentous fungi
• Grantee: Luis Henrique Souza Guimaraes
• Support Opportunities: Regular Research Grants