Many natural products from plant-based foods, herbal medicinal products and dietary supplements are not absorbed in the upper gastrointestinal tract. These substances reach the large intestine, where they come in contact with the gut microbiome. The gut microbiome constitutes a complex community of microorganisms that plays an important role in maintaining the health of its human host. The gut microorganisms can biotransform many natural products. Thereby, new metabolites are produced that may be absorbable and have different pharmacological effects than their parent compounds. They can therefore be of great importance for the pharmacological efficacy of medicinal plants and herbal medicinal products. On the other hand, natural compounds that enter the colon can also modulate the composition of the gut microbiome. Certain classes of natural products have a prebiotic effect, which means that they support the growth of health-promoting microorganisms.
We are investigating such interactions between natural compounds and the gut microbiome in collaboration with the research group of Univ.-Prof. Dr. Christine Moissl-Eichinger at the Medical University of Graz by incubating natural compounds or herbal extracts with fecal suspension that is rich in gut microorganisms. The chemical changes in the natural product profile are tracked using liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS), and the changes in the composition of the gut microbiome are traced back using modern sequencing techniques (16s rRNA gene sequencing and metagenomic sequencing).
