September 17, 2026, at 10:00 a.m.
FGÚ Lecture Hall (Vídeňská 1083, 142 20 Prague 4 – Krč)
The defense of the dissertation “Microbiome Enzymes to Produce Flavonoid Metabolites, Their Biological Activity, and Use in Metabolic Studies” by Assoc. Prof. Ing. Kateřina Valentová, Ph.D., will take place on September 17, 2026, at 10:00 a.m. before the Committee on Microbiology, Virology, and Mycology at the Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague 4 – Krč, in the conference room/auditorium. Information is available on the Czech Academy of Sciences website.
Opponents
| Prof. Cristian Del Bo’ | University of Milan, DeFENS-Division of Human Nutrition, Itálie |
| Dr. Antonio González-Sarrías | CEBAS-CSIC Campus de Espinardo, Food and Technology Department, Španělsko |
| prof. Dr. RNDr. Oldřich Lapčík | VŠCHT, Fakulta potravinářské a biochemické technologie |
Assoc. Prof. Ing. Kateřina Valentová, Ph.D.
Biochemist specializing in the metabolism, bioavailability, and bioactivity of plant polyphenols, especially milk thistle flavonolignans. She holds a PhD in Medical Chemistry and Biochemistry from Palacký University Olomouc, where she later habilitated as Associate Professor. She serves as Deputy Head of the Laboratory of Biotransformation and Deputy Director for HR Award at the Institute of Microbiology of the CAS. Her research focuses on polyphenol metabolism in humans, chemoenzymatic preparation of metabolites, and interindividual variability in metabolism and biological activityof polyphenols. In 2023, she chaired the 4th International Conference on Food Bioactives & Health in Prague.
This dissertation focuses on the use of microbial enzymes for the production of flavonoid metabolites, the evaluation of their biological activity, and metabolic studies. After ingestion, flavonoids undergo extensive biotransformation in the human body (deglycosylation, C-ring cleavage, conjugation), so that the circulating forms differ significantly from the original compounds.
The first part focuses on microbial enzymes as selective biocatalysts for the synthesis of metabolites (glycosidases, dioxygenases, sulfotransferases, glucuronidation). The second part evaluates the bioactivity of conjugated and microbially transformed metabolites — conjugation does not interfere with biological activity but alters selectivity, cellular uptake, and interactions with enzymes and transporters. The third part integrates metabolic studies, the role of the gut microbiota, and LC–MS metabolomics.
The study demonstrates that microbial enzyme technology, combined with biological evaluation, provides a comprehensive platform to study the fate and function of polyphenols in the human body.