Analysis of fermentation selectivity of purified galacto-oligosaccharides by in vitro human faecal fermentation

作者：Rodriguez Colinas Barbara; Kolida Sofia; Baran Magdalena; Ballesteros Antonio O; Rastall Robert A; Plou Francisco J^*

来源：Applied Microbiology and Biotechnology, 2013, 97(13): 5743-5752.

DOI：10.1007/s00253-013-4892-z

• Batch culture system
• Galacto-oligosaccharides
• Prebiotics
• Transglycosylation
• beta-Galactosidase
• FISH
• Short-chain fatty acids

The in vitro fermentation of several purified galacto-oligosaccharides (GOS), specifically the trisaccharides 4%26apos;-galactosyl-lactose and 6%26apos;-galactosyl-lactose and a mixture of the disaccharides 6-galactobiose and allolactose, was carried out. The bifidogenic effect of GOS at 1 % (w/v) was studied in a pH-controlled batch culture fermentation system inoculated with healthy adult human faeces. Results were compared with those obtained with a commercial GOS mixture (Bimuno-GOS). Changes in bacterial populations measured through fluorescence in situ hybridization and short-chain fatty acid (SCFA) production were determined. Bifidobacteria increased after 10-h fermentation for all the GOS substrates, but the changes were only statistically significant (P%26lt;0.05) for the mixture of disaccharides and Bimuno-GOS. Acetic acid, whose formation is consistent with bifidobacteria metabolism, was the major SCFA synthesized. The acetate concentration at 10 h was similar with all the substrates (45-50 mM) and significantly higher than the observed for formic, propionic and butyric acids. All the purified GOS could be considered bifidogenic under the assayed conditions, displaying a selectivity index in the range 2.1-3.0, which was slightly lower than the determined for the commercial mixture Bimuno-GOS.

• 出版日期2013-7