Significant progress has been achieved in the first year of the FIBRE-MATCH project especially on setting up the workflows for sequence-based and phenotypic assessment of the individual variations in the capacity of the gut microbiota to metabolise different DFs. This includes processing of ca. 1700 gut metagenome samples for identification and relative quantification of DF-active functional characteristics of individual samples, and testing of various microbiome clustering approaches (WP1). We primarily focused on identifying and quantifying fibre-degrading enzymes (glycoside hydrolases and polysaccharides, as denoted by their EC number) with complementary analysis of carbohydrate-active enzymes (CAZymes). Preliminary clustering analysis based on fibre degradation enzyme abundance revealed a bimodal distribution, with samples segregating into high and low fibre degradation potential groups across all fibre types. A parallel computational pipeline was developed to predict net intestinal gas using gas-related enzymes. In vitro (WP2), methodology have been developed, applied and optimised for microplate experiments for initial assessment of growth of selected bacterial samples (communities) on eight different DFs, followed by test-tube experiments for the measurement of acid and gas production of the fecal cultures on the same DFs. The results indicate that the metabolite patterns depended more on fecal culture but also on the substrate, with high dependence on the pH. The fibre sources preliminary selected to be used for the food prototypes in the WP4 trials are rye bran, oat bran, and faba bean. The chemical composition of samples of two rye brans (Finnish and Estonian) and oat bran as well as their fermented counterparts and fermented and baked rye bran were analysed for monosaccharides, starch, β-glucan, fructan, and protein (WP3). The composition differed depending on the fibre sources and processing. The results are utilised to develop fibre-rich food prototypes such as fibre-rich powder for addition to smoothies or similar products, fibre-rich snacks such as crisp bread, and fibre-rich bread in the clinical trials.
