In vitro fermentation of lactulose-derived oligosaccharides by mixed fecal microbiota

Cardelle-Cobas, A., Olano, A., Corzo, N., Villamiel, M., Collins, M., Kolida, S. and Rastall, B. (2012) In vitro fermentation of lactulose-derived oligosaccharides by mixed fecal microbiota. Journal of Agricultural and Food Chemistry , 60 (8). pp. 2024-2032. ISSN 0021-8561 doi: 10.1021/jf203622d

Abstract/Summary

Fermentation properties of oligosaccharides derived from lactulose (OsLu) and lactose (GOS) have been assessed in pH-controlled anaerobic batch cultures using lactulose and Vivinal-GOS as reference carbohydrates. Changes in gut bacterial populations and their metabolic activities were monitored over 24 h by fluorescent in situ hybridization (FISH) and by measurement of short-chain fatty acid (SCFA) production. Lactulose-derived oligosaccharides were selectively fermented by Bifidobacterium and lactic acid bacterial populations producing higher SCFA concentrations compared to GOS. The highest total SCFA production was from Vivinal-GOS > lactulose > OsLu > GOS. Longer incubation periods produced a selective fermentation of OsLu when they were used as a carbon source reaching the highest selective index scores. The new oligosaccharides may constitute a good alternative to lactulose, and they could belong to a new generation of prebiotics to be used as a functional ingredient for improving the composition of gut microflora.