Galactoglucomannan Extracted from Spruce (Picea abies) as a Carbohydrate Source for Probiotic Bacteria

A prebiotic is a nonviable food component that confers a health benefit on the host associated with modulation of the microbiota. Hemicelluloses are the second most common group of polysaccharides in nature and they occur in plant cell walls. The predominant hemicellulose in softwood species is galactoglucomannan, and based on its chemical structure and information available about similar saccharides, galactoglucomannan may be postulated to have prebiotic properties. In this study we demonstrated that Bifidobacterium species are able to ferment hemicellulose-derived saccharides. Significant stimulatory effects on the growth rates of bifidobacteria were found when galactoglucomannan or its hydrolysis products were present. Bifidobacterium animalis subsp. lactis strain Bb12, a commonly used probiotic, was able to adapt to the galactoglucomannan leading to more efficient utilization of hemicellulose-derived saccharides. Our study demonstrates prebiotic properties for galactoglucomannan and warrants the next step, that is, characterization of the effects of galactoglucomannan in food.