Immobilization of an alpha-galactosidase from Debaryomyces hansenni UFV-1 in cellulose film and its application in oligosaccharides hydrolysis

Debaryomyces hansenii UFV-1 α-galactosidase was partially purified and immobilized in a cellulose film. The immobilization preserved 97% of the initial enzyme activity. The optimal pH levels of free and immobilized α-galactosidases were 5.0 and 4.0, respectively, and the optimal temperatures were 60 and 85 °C, respectively. The immobilized α-galactosidase exhibited higher stability at 85 °C for a period of 40 h. The α-galactosidase maintained above 80% of its original activity even after ten consecutive reuse of the film. The storage of the film at room temperature preserved the enzyme activity. The soymilk treatment with immobilized enzyme for 16 and 20 h, at 60 °C, with or without agitation, respectively, reduced stachyose and raffinose contents completely.