New beta-galactosidase producers with potential for prebiotic synthesis

• Type: Article in International Scientific Journal
• Date: 2018

Authors

Eugénia A. Macedo (Author) FEUP; Sara C. Silvério (Author) Other; José A. Teixeira (Author) Other; Lígia R. Rodrigues (Author) Other

Journal

Title: Bioresource Technology

Vol. 250

Pages: 131-139

ISSN: 0960-8524

Publisher: Elsevier

Indexing

ISI Web of Science

Scopus

Scientific classification

CORDIS: Technological sciences

FOS: Engineering and technology

Other information

DOI: 10.1016/j.biortech.2017.11.045

Abstract (EN): beta-Galactosidases (EC 3.2.1.23) are interesting enzymes with potential application in the pharmaceutical and food industry. In this work, a screening study was carried out to identify new fungal sources of beta-galactosidase. A total of 50 fungi were evaluated using a chromogenic test performed in agar plates. The most promising microorganisms were validated as effective beta-galactosidase producers under submerged fermentation conditions. The crude beta-galactosidases were characterized regarding their optimal pH (3.0-5.5) and temperature (45-65 degrees C). All enzymes showed ability to synthesize lactose-based prebiotics, namely lactulose (maximal yield 3.3%) and a galacto-oligosaccharide (GOS) (maximal yield 20%). Additionally, some enzymatic extracts with fructosyltransferase activity allowed to produce other type of prebiotics, namely fructo-oligosaccharides (FOS). This work, reports for the first time the simultaneous synthesis of different mixtures of GOS (2-15% yield and 0.07-0.5 g/L.h(-1) productivity) and FOS (4-30% yield and 0.1-1 g/L.h(-1) productivity) by crude extracts exhibiting dual enzymatic activity.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9