A team of international researchers called on further in vivo studies to confirm their results for ‘raffinose-derived’ oligosaccharides but said, “these carbohydrates could be considered as a new and alternative source of prebiotics.”
“In addition, these oligosaccharides generated a similar volume of gas as commercial inulin,” they added referring to previous studies that had raised flatulence issues with similar oligosaccharide forms.
One of the researchers, Professor Bob Rastall, from the University of Reading in the UK, told NutraIngredients the research was part of a larger programme he and others wee involved in to investigate the healthful properties of novel prebiotic fibres including dextran-bran and pectin.
“Many of them have little or no commercial use as prebiotics at the moment, but the results are confirming benefits, in vitro at least,” he said.
For the current study, pre-published this month in the Journal of Agricultural and Food Chemistry, raffinose pentahydrate, lactulose and sucrose bought from Beneo-Orafti and Sigma Aldrich Corp, was formed into the ‘raffinose-derived’ oligosaccharide and delivered to small-scale pH-controlled batch cultures at 37ºC under anaerobic conditions with human faeces.
“The molecular weight of oligosaccharides is very likely relevant to their prebiotic activity,” the researchers concluded, “and although some studies suggest that carbohydrates with higher degree of polymerisation could reach the more distal regions of the gut where most of disorders take place, lower molecular weight oligosaccharides present higher bifidogenic activity.”
“However, more studies are required with oligosaccharides of higher DP [degree of polymerisation] to confirm this behaviour.”
Journal of Agricultural and Food Chemistry
‘In vitro fermentation of alternansucrase raffinose-derived oligosaccharides by human gut bacteria’
Authors: Oswaldo Hernandez-Hernandez, Greg L. Cote, Sofia Kolida, Robert A Rastall, and Maria Luz Sanz