Discovery of components in food crops that affect the gut microbiome and how food processing affects bioavailability.
Plant geneticists, breeders, and biochemists work with microbiologists and food scientists to identify components in food crops that affect the human gut microbiome. These groups rely heavily on in vitro digestion-fermentation systems to study how genetic variation in cereal grains can influence digestion by the human body and fermentation by the gut microbiome. The in vitro approaches enable hundreds to thousands of genotypes of corn, sorghum, wheat, and other food crops to be tested (phenotyped) for their ability to drive unique digestion-fermentation patterns by the microbiome. Genetic association studies then link the unique microbiome fermentation patterns to specific segments of the plant genome where genetic variation (variation in specific sets of genes) is driving variation in composition of the seed, which in turn drives the microbiome phenotypes. In this way, cereal crops such as corn, wheat, sorghum, and millet or pulses and legumes (e.g. dry beans) can be bred to enhance traits that promote growth of beneficial, desirable microorganisms. For example, certain varieties of corn carry naturally-occurring mutations that affect starch composition (amylose:amylopectin ratio), which ultimately influences how much of the resistant starch survives digestion in the upper GI tract and transits into the colon to feed beneficial microbes in the large intestine.
Microbiome active components and Food Processing
To better understand how foods can be formulated and produced with maximum benefits for the microbiome, discovery teams are also studying how food processing can affect the bioactivity and bioavailability of food components on the gut microbiome. For example, how do different types of thermal processing (baking, steaming, extrusion) affect starch or fiber structures from cereal grains and in turn, change how they are digested and fermented by the gut microbiome.
Pre-clinical Testing
The center also supports pre-clinical animal model systems such as the gnotobiotic mouse models where food components and ingredients found in in vitro discovery research can be tested in the context of an intact digestive tract-microbiome. Such studies enable center members to determine if microbiome activity of a food or ingredient not only affects the microbiome, but also how it can affect host outcomes such as weight gain, physiological outcomes such as glucose tolerance, or immunological outcomes such as inflammation.
Human Clinical Testing
Ultimately, the efficacy of Foods designed to promote health and disease prevention must be evaluated in human clinical research. Here NFHC researchers study the effects of such novel foods on the gut microbiome and a variety of health outcomes using state-of-the-art clinical facilities at the UNL and UNMC campuses. The clinics are designed to facilitate participant education and to simplify participation in research studies.