Production of α- and β-Galactosidases from Bifidobacterium longum subsp longum RD47

Approximately 50% of people in the world experience abdominal flatulence after the intake of foods containing galactosides such as lactose or soybean oligosaccharides. The galactoside hydrolyzing enzymes of alpha- and beta-galactosidases have been shown to reduce the levels of galactosides in both the food matrix and the human gastrointestinal tract. This study aimed to optimize the production of alpha- and beta-galactosidases of Bifidobacterium longum subsp. longum RD47 with a basal medium containing whey and corn steep liquor. The activities of both enzymes were determined after culturing at 37 degrees C at pH 6.0 for 30 h. The optimal production of alpha- and beta-galactosidases was obtained with soybean oligosaccharides as a carbon source and proteose peptone no. 3 as a nitrogen source. The optimum pH for both alpha- and beta-galactosidases was 6.0. The optimum temperatures were 35 degrees C for a-galactosidase and 37 degrees C for beta-galactosidase. They showed temperature stability up to 37 degrees C. At a 1 mM concentration of metal ions, CuSO4 inhibited the activities of alpha- and beta-galactosidases by 35% and 50%, respectively. On the basis of the results obtained in this study, B. longum RD47 may be used for the production of alpha- and beta-galactosidases, which may reduce the levels of flatulence factors.