Effects of dietary fibers studied in vivo and in vitro by metabolomics

This PhD project involves use of metabolomics in human nutrition. More specifically, the aim of the present PhD project is to develop and apply metabolomics tools to elucidate the impact of dietary fibers on the gut metabolome. Fiber contributes to a balanced gastrointestinal tract, and a high fiber diet helps to improve digestive health. Clinical studies have shown that polydextrose (PDX) offer benefits for the digestive health, such as improved bowel functions, increased production of short chain fatty acids (SCFAs) through colonic microbial fermentation, protective activities for markers of colorectal cancer, decrease in colonic pH and reduced glucose absorption in the small intestine. In addition, an improved digestive health is also obtained due to selective growth of beneficial bacteria, such as bifidobacteria and lactobacilli. This PhD project includes two parts; i) an in vitro study using an colon simulator (Enteromix colon simulator) and ii) a human intervention study aiming at comparing the differences of the microbiota and metabolome between healthy subjects consuming PDX or not. These parts will take place in collaboration with DuPont, Dept. Active Nutrition in Finland and DuPont N&H, Advanced Analysis, Brabrand (DK). Focus in this PhD project is on the development and use of metabolomics to study fecal sample material collected from these studies.