Undigestibility of galactooligosaccharides

• Published in: Nihon Shokuhin Kagaku Kōgaku kaishi Vol. 51; no. 1
• Main Authors: Chonan, O. (Yakult Co. Ltd., Kunitachi, Tokyo (Japan). Inst. for Microbiological Research), Shibahara Sone, H, Takahashi, R, Ikeda, M, Kikuchi Hayakawa, H, Ishikawa, F, Kimura, K, Matsumoto, K
• Format: Journal Article
• Language: Japanese
• Published: 01.01.2004
• Subjects: DIGESTIBILITY; GALACTOSIDASES; IN VITRO EXPERIMENTATION; OLIGOSACCHARIDES
• ISSN: 1341-027X
• DOI: 10.3136/nskkk.51.28

To test the digestibility of galactooligosaccharides (GOS) prepared from lactose through the transgalactosylation reaction of Sporobolomyces singularis cells and v-galactosidase from Kluyveromyces lactis, hydrogen gas in the exhalation of sixteen healthy subjects given GOS was analyzed. Hydrogen excretion following ingestion of GOS was substantially greater than that following ingestion of placebo. This fact shows that GOS was a mixture of non-digestible saccharides. Furthermore, to clarify non-digestible ingredients in GOS, we separated transgalactosylated di-, tri- and tetra-saccharides from GOS by Bio-Gel P-2 column, respectively. Then, resistance of these saccharides to the digestive enzymes was studied in vitro. The samples which contain di-, tri-, and tetra-saccharides were not digested in vitro by a-amylase of human saliva, the artificial gastric juice, and a-amylase of hog pancreas, but di-saccarides were partially digested by the enzymes of rat intestinal acetone powder. These results show that hydrogen excretion following ingestion of GOS was associated with bacterial degradation of tri-, and tetra-saccharides and some of di-saccarides in GOS after passing undigested through the small intestine into the large bowel.