Extracellular α-Galactosidase from Debaryomyces hansenii UFV-1 and Its use in the hydrolysis of raffinose oligosaccharides

• Autor(a) principal: Rezende, Sebastião T. de
• Data de Publicação: 2006
• Outros Autores: Marques, Virgínia M., Trevizano, Larissa M., Passos, Flávia M. L., Oliveira, Maria G. A., Bemquerer, Marcelo P., Oliveira, Jamil S., Guimarães, Valéria M., Viana, Pollyanna A.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://dx.doi.org/10.1021/jf0526442; http://www.locus.ufv.br/handle/123456789/19902
• topic: α-Galactosidase; Debaryomyces hansenii UFV-1; Raffinose oligosaccharides; Characterization; Flatulence

Raffinose oligosaccharides (RO) are the factors primarily responsible for flatulence upon ingestion of soybean-derived products. ROs are hydrolyzed by α-galactosidases that cleave α-1,6-linkages of α-galactoside residues. The objectives of this study were the purification and characterization of extracellular α-galactosidase from Debaryomyces hansenii UFV-1. The enzyme purified by gel filtration and anion exchange chromatographies presented an Mr value of 60 kDa and the N-terminal amino acid sequence YENGLNLVPQMGWN. The Km values for hydrolysis of pNPαGal, melibiose, stachyose, and raffinose were 0.30, 2.01, 9.66, and 16 mM, respectively. The α-galactosidase presented absolute specificity for galactose in the α-position, hydrolyzing pNPGal, stachyose, raffinose, melibiose, and polymers. The enzyme was noncompetitively inhibited by galactose (Ki = 2.7 mM) and melibiose (Ki = 1.2 mM). Enzyme treatments of soy milk for 4 h at 60 °C reduced the amounts of stachyose and raffinose by 100%.