Hagerman Lab
Research Overview
Tannins are plant natural products that have molecular weights of at least 500 g/mol, that have more than one phenolic moiety, and that form stable complexes with proteins. Tannins are constituents of the larger class of plant products known as polyphenolics, but tannins are unique in their ability to precipitate proteins and in their high affinity for proline rich proteins. They are also potent antioxidants and chelate metals such as iron or copper. We are interested in the bioactivities of tannins found in the human diet (tea, wine, chocolate, fruits) and in the ecological significance of tannins found in natural systems (soils, plant herbivory). In particular, we use purified tannins to establish structure-activity relationships with the long term goal of understanding of tannins as individual bioactive compounds. Many of the analytical tools that we use can be found in the Tannin Handbook (see drop down menu).
Grad students in the lab generally pursue bioanalytical and structural biology related projects and find careers in industry or academics. Undergraduates learn natural product isolation, bioactivity assays, HPLC, mass spec, and data analysis. Career paths for previous undergrads in the lab include graduate school, medical school, or food/beverage industry positions. Visit the Lab Members page to learn more about our students.
Watch the first webinar on polyphenols sponsored by the Groupe Polyphenols in April 2022!
Current projects
We are engaged in a large, collaborative project that is using "omics" science and chemistry to discover pathways for condensed tannin biodegradation by microbial populations. Condensed tannins are found in the gut, where they impact the gut microbiome; in the rumen, where they influence the rumen microbiome; and in soils, where they affect the soil microbiome. Although tannin inputs into these systems may be large, the detailed metabolic fate and effects of condensed tannins in any microbiome are unknown. By collaborating with a soil microbiology team (Kelly Wrighton's group at Colorado State University) we are using chemical tools such as HPLC, chemical degradtion analysis, and mass spectrometry in combination with genomics, proteomics and metabolomics approaches to elucidate the metabolism of Sorghum procyanidin in soils. We have already identified conditions where the 16-mer tannin polymer is degraded to smaller products, and have preliminary identification of the active organisms. Our lab is responsible for detailing the steps for decomposition of the polymer and characterizing products. We also provide all of the condensed tannin for the project, requiring purification and confimation of purity of large amounts of tannin.